TD-04-013

May 12, 2004

RESULTS OF Nb~3~Sn CABLE TESTS AT SELF-FIELD USING THE UPGRADED SC
TRANSFORMER

E. Barzi, D. Turrioni

[Abstract:]{.underline}

A 28 kA SC transformer \[1\] was used to measure the quench current of
PIT and MJR SC cables at self-field under various cooling conditions.
Using the existing SSTF and strand power supply makes this an efficient
way to a fast turn-around and reliable data. A fast DAQ system \[2\]
allows a real-time acquisition of the secondary current, as well as
recording each quench pattern by means of voltage taps placed along the
sample. The results obtained in the first systematic run of thirteen
Nb~3~Sn cable tests are herein described.

1.  INTRODUCTION

To investigate cable instability, which is a phenomenon that shows
itself at low fields, cable tests at self-field using the existing SSTF
and strand power supply is an economic way to a fast turn-around and
reliable data. To make this also an efficient and useful system for
magnet R&D, the upgraded transformer was designed to provide a maximum
current in the secondary winding close to 28 kA, which is a typical
short sample limit for Small Racetracks with strand J~c~'s of 2000
A/mm^2^. The short sample limits of Cos-theta models are typically close
to 25 kA for the same strand critical current densities. The upgraded
transformer is being extensively used to test impregnated and
non-impregnated cables, enabling investigation of the various effects
that have been tied to cable instability, such as d~eff~, matrix
resistivity, RRR and cooling. This note reports in detail the results
obtained in a first systematic run of thirteen cable tests, including
impregnated 28 x 1 mm rectangular PIT, impregnated and non-impregnated
28 x 1 mm keystoned MJR, and impregnated and non-impregnated 41 x 0.7 mm
rectangular MJR cables of the react & wind type.

2.  STRAND AND CABLE DESCRIPTION

The parameters of the thirteen cable samples that were tested are shown
in Table I. The PIT and MJR2 cables were fabricated at FNAL, whereas the
MJR1 and MJR3 cables were fabricated at LBNL. All cables had the same
pitch length of about 110 mm, corresponding to a transposition angle of
14.50.1 degree for the 28-strand cables and of 15.40.1 degree for the
41-strand cables. The "R" and "KS" under "Cable Geometry" in Table I
denote rectangular and keystoned cables respectively. For the keystoned
cables, the keystone angle was 0.90.1 degree. The SS core material is
9.52 mm by 0.025 mm, 316-L annealed. The heat treatment (HT) cycles are
shown in Table III. Three different multifilamentary Modified Jelly Roll
(MJR) Nb~3~Sn strands by Oxford Superconducting Technology (OST), and
one Powder-in-Tube strand by ShapeMetal Innovation (SMI) were used to
manufacture the cables. The strands parameters are shown in Table II.
Close-ups of cross sections of the rectangular PIT and the keystoned
MJR2 cables after reaction are shown in Figs. 1 and 2 respectively.

The SC transformer and test facility, sample preparation,
instrumentation and mounting, and data acquisition and test procedure
are described in \[1, 2\].

Table I. Parameters of tested cable samples.

  -------- -------- -------- -------- ---- ----- ------ ---------- ------ -------------- ---------- -------------
  Sample   Strand   Strand   Strand   HT   RRR   PF, %  Cable      SS     Impregnation   Test Date  Special Notes
  No.      Type     Size, mm No.                        Geometry   Core                  (2004)     

  1        PIT      1.0      28       A    \~ 90 88.6   R          N      Y              03/24      Ceramic
                                                                                                    Insulation &
                                                                                                    Binder

  2        PIT      1.0      28       A    \~ 90 88.6   R          N      Y              03/29,30   "

  3        MJR1     1.0      28       B    \~ 5  88.6   KS         N      Y              01/09      Ceramic
                                                                                                    Insulation &
                                                                                                    Binder

  4        MJR1     1.0      28       B    \~ 5  88.6   KS         N      Y              04/01      "

  5        MJR2     1.0      28       C    \~ 50 88.4   KS         Y      N              03/25      Ceramic
                                                                                                    Insulation &
                                                                                                    Binder

  6        MJR2     1.0      28       C    \~ 50 88.4   KS         Y      Y              04/15      "

  7        MJR2     1.0      28       C    \~ 50 88.4   KS         Y      Y              04/23      "

  5a       MJR2     1.0      28       C    \~ 50 88.4   KS         Y      Y              05/03      Is Sample 5
                                                                                                    impregnated

  8        MJR3     0.7      41       B    \~ 5  85.6   R          N      N              04/21      React & Wind

  9        MJR3     0.7      41       B    \~ 5  85.6   R          N      N              05/12      "

  10       MJR3     0.7      41       B    \~ 5  85.6   R          N      Y              04/19      R&W, E-glass
                                                                                                    sleeve

  11       MJR3     0.7      41       B    \~ 5  85.6   R          N      Y              04/22      "  , "

  8a       MJR3     0.7      41       B    \~ 5  85.6   R          N      Y              04/27      Is Sample 8
                                                                                                    impregnated
  -------- -------- -------- -------- ---- ----- ------ ---------- ------ -------------- ---------- -------------

Table II. Parameters of the strands used in the cables.

  ------------------- ------------ ------------- ------------- ------------
  Strand Parameter    MJR1         MJR2          MJR3          PIT

  Strand diameter, mm 1.0000.001   1.0000.001    0.70.001      1.0000.001

  I~c~(12T), A        \~ 700       \~ 730        \~ 400        \~ 700

  d~eff~, m           \~ 110       \~ 110        \~ 80         \~ 50

  Cu, %               47.8 0.3     46.7 0.3      47 0.3        53.6 0.3

  Twist pitch,        23 3         23 3          15 3          20 3
  mm/turn                                                      
  ------------------- ------------ ------------- ------------- ------------

**Table III. Heat treatment cycles.**

+-----+----------------+---------------+---------+---------+---------+
| H   |                |               | Step 1  | Step 2  | Step 3  |
| eat |                |               |         |         |         |
| Tre |                |               |         |         |         |
| atm |                |               |         |         |         |
| ent |                |               |         |         |         |
+-----+----------------+---------------+---------+---------+---------+
| #   | #              | Ramp rate,    | 25      |         |         |
|  {# | {#section-1 .R | ^o^C/h        |         |         |         |
| sec | eference-Head} |               |         |         |         |
| tio |                |               |         |         |         |
| n . |                |               |         |         |         |
| Ref |                |               |         |         |         |
| ere |                |               |         |         |         |
| nce |                |               |         |         |         |
| -He |                |               |         |         |         |
| ad} |                |               |         |         |         |
+-----+----------------+---------------+---------+---------+---------+
| #   | # **SM         | Temperature,  | 655     |         |         |
|  ** | I_NOMINAL** {# | ^o^C          |         |         |         |
| A** | smi_nominal .R |               |         |         |         |
|  {# | eference-Head} |               |         |         |         |
| a . |                |               |         |         |         |
| Ref |                |               |         |         |         |
| ere |                |               |         |         |         |
| nce |                |               |         |         |         |
| -He |                |               |         |         |         |
| ad} |                |               |         |         |         |
+-----+----------------+---------------+---------+---------+---------+
|     |                | Duration, h   | 170     |         |         |
+-----+----------------+---------------+---------+---------+---------+
| #   | #              | Ramp rate,    | # 25    | 50      | 75      |
|   { | {#section-3 .R | ^o^C/h        | {#secti |         |         |
| #se | eference-Head} |               | on-4 .R |         |         |
| cti |                |               | eferenc |         |         |
| on- |                |               | e-Head} |         |         |
| 2 . |                |               |         |         |         |
| Ref |                |               |         |         |         |
| ere |                |               |         |         |         |
| nce |                |               |         |         |         |
| -He |                |               |         |         |         |
| ad} |                |               |         |         |         |
+-----+----------------+---------------+---------+---------+---------+
| #   | # **OS         | Temperature,  | # 210   | 340     | # 650   |
|  ** | T_NOMINAL** {# | ^o^C          | {#secti |         | {#secti |
| B** | ost_nominal .R |               | on-5 .R |         | on-6 .R |
|  {# | eference-Head} |               | eferenc |         | eferenc |
| b . |                |               | e-Head} |         | e-Head} |
| Ref |                |               |         |         |         |
| ere |                |               |         |         |         |
| nce |                |               |         |         |         |
| -He |                |               |         |         |         |
| ad} |                |               |         |         |         |
+-----+----------------+---------------+---------+---------+---------+
|     |                | Duration, h   | 100     | 48      | 180     |
+-----+----------------+---------------+---------+---------+---------+
| #   | #              | Ramp rate,    | # 25    | 50      | 75      |
|   { | {#section-8 .R | ^o^C/h        | {#secti |         |         |
| #se | eference-Head} |               | on-9 .R |         |         |
| cti |                |               | eferenc |         |         |
| on- |                |               | e-Head} |         |         |
| 7 . |                |               |         |         |         |
| Ref |                |               |         |         |         |
| ere |                |               |         |         |         |
| nce |                |               |         |         |         |
| -He |                |               |         |         |         |
| ad} |                |               |         |         |         |
+-----+----------------+---------------+---------+---------+---------+
| #   | #              | Temperature,  | # 210 { | 340     | # 650 { |
|  ** | **OST_SHORT**  | ^o^C          | #sectio |         | #sectio |
| C** | {#ost_short .R |               | n-10 .R |         | n-11 .R |
|  {# | eference-Head} |               | eferenc |         | eferenc |
| c . |                |               | e-Head} |         | e-Head} |
| Ref |                |               |         |         |         |
| ere |                |               |         |         |         |
| nce |                |               |         |         |         |
| -He |                |               |         |         |         |
| ad} |                |               |         |         |         |
+-----+----------------+---------------+---------+---------+---------+
|     |                | Duration, h   | 100     | 48      | 72      |
+-----+----------------+---------------+---------+---------+---------+

![](media/image1.png){width="4.003472222222222in"
height="2.997916666666667in"}

Fig. 1. Close-up of cross section of rectangular PIT cable after
reaction (Ryuji Yamada courtesy).

![](media/image2.png){width="4.852777777777778in" height="3.2375in"}

Fig. 2. Close-up of cross section of keystoned MJR2 cable after reaction
(Ryuji Yamada courtesy).

3.  RESULTS AND DISCUSSION

In the following, a summary of the test results at self-field is shown
for every family of cables, i.e. the PIT, MJR1, MJR2 and MJR3 cables. To
evaluate the self-field of each test, the load line of the secondary
winding is given for convenience in Fig. 10 in Appendix. Details on each
cable test run can also be found in Appendix, including the voltage tap
schematic (Figs. 11 to 14) that was used for the fast DAQ, a table with
comprehensive information on the transformer parameters and splice
resistance (Tables IV to XVI) for each test number, a plot of the
maximum currents or of the quench history where primary ramp rates are
also specified (Figs. 15 to 27), and in the case of quench, typical
patterns that were found for the voltage signals (Figs. 28 to XX).

1.  28 x 1 mm Rectangular PIT Cables

***Results***

Test results for Samples 1 and 2, which are impregnated rectangular
cables made of 28 x 1 mm PIT strands, heat treated using the SMI nominal
cycle (HT A, RRR \~ 90), are shown in Figs. 3 and 4. Closed markers
denote reaching maximum current without quenching, open markers
represent quenches. Sample 1, which is the only sample that was tested
without operating at all the fast DAQ, reached a maximum current of
23,332A ^+30A^~-0A~ without quenching, as obtained with the 0.8 Hz
standard system, and using a primary ramp rate of 20 A/s. Details of the
tests are reported in Table IV and Fig. 15. To account for the
inaccuracy of the slow DAQ system, error bars are shown in Figure below
for all data points associated to tests performed without fast DAQ.

In the case of a sample that does not quench up to maximum secondary
currents, the higher the ramp rate with which the primary coil is ramped
down, the larger the current induced in the secondary, as the time for
the secondary current to decay is shorter. Sample 2 was therefore tested
at increasing ramp rates to push the secondary current as high as
possible. Details of the tests are reported in Table V and Fig. 16. In a
first test run encompassing Test Nos. 1 to 18, the sample showed some
training, with a first quench at 24,120A ^+2,200A^~-0A~ before reaching
a maximum current of 26,708 A without quenching, with a primary current
of 724 A and a ramp rate of 100 A/s. However, the sample quenched again
at 26,600 A using a ramp rate of 120 A/s. After such quench, some damage
occurred to the splices as confirmed by two subsequent quenches at
around 20 kA, and by monitoring the splices resistance during the run.
Splices resistance is measured from the decay of the secondary winding
using an inductance *L2* of 0.23 H. As detailed in Table V, at the start
of the test run, the splices resistance was 1.55 n at about 24 kA. After
the first quench it was 1.72 n at about 25 kA, but after the second
quench it peaked to 5.29 n at 15 kA. The corresponding resistances at a
current level of 5 kA were 1.15 n, 1.15 n, and 4.35 n. The test run was
then stopped, the transformer extracted from the cryostat and the sample
properly re-spliced. In the second test run, which included Test Nos. 19
to 34, Sample 2 showed again some training by quenching at 25,627 A with
a ramp rate of 80 A/s. After such quench, the splices resistance went up
by only 0.6 n at about 26 kA from 1.6 n at 25.5 kA and the sample
reached a maximum current of 26,623 A without quenching anymore, with a
primary current of 756 A and a ramp rate of 150 A/s.

***Discussion***

The good consistency between the results of Sample 1 and Sample 2, and
the excellent reproducibility of Sample 2 behavior after a thermal
cycle, especially the values of the maximum quench currents in each run,
indicate that these PIT cables are close to their stability limits at
levels of current of about 26 kA. This would be consistent with SR01
test results at 2.2 K \[3\], where a quench current cut-off was observed
at about 24.2 kA, albeit the expected short sample limit that had been
calculated from strand data at 2.2K was 26.1 kA. As in that case the
cable was subject to a transverse load that caused at that field a
critical current degradation of about 10%, whereas in the transformer
setup no substantial load is applied to the sample, such cut-off could
have been predicted to be between 23.6 kA and 24.5 kA by reducing the
quench current range observed in the cable test (i.e. 25,627 A to 26,600
A) by about 10%.

![](media/image3.wmf)

**Fig. 3.** Test results for an impregnated rectangular cable (Sample 1)
made of 28 x 1 mm PIT strands, heat treated using the SMI nominal cycle
(HT A, RRR \~ 90).

![](media/image4.wmf)

**Fig. 4.** Test results for an impregnated rectangular cables (Sample
2) made of 28 x 1 mm PIT strands, heat treated using the SMI nominal
cycle (HT A, RRR \~ 90). Closed markers denote reaching maximum current
without quenching, open markers represent quenches.

2.  28 x 1 mm Keystoned MJR1 Cables

*Results*

The quench history results for Samples 3 and 4, which are impregnated
keystoned cables made of 28 x 1 mm MJR1 strands, heat treated using the
OST nominal cycle (HT B, RRR \~ 5), are plotted in Fig. 5. Two identical
cables were simultaneously measured at various magnetic fields at the
cable test facility at BNL \[4\]. In all cases, the cable samples
quenched at around some average current. For Sample 3 such current was
14,686 A with a width (stdev) of 608 A. For Sample 4 it was 10,194 A 432
A. The average quench current including both tests would be 12,248 A
with a width (stdev) of 2,306 A. Details of the tests are reported in
Table VI and VII and Figs. 17 and 18.

*Discussion*

In both cases, the quench current width is about 4%, as in \[4\] where
the average quench current was 15,040 A 588 A. Including all ramp rates,
for Sample 3 the 2,547 A difference between maximum and minimum quench
currents is 17.3% of the average current, for Sample 4 such difference
is 1,657, i.e. 16.3% of the average current, and for \[4\] it is 2,967
A, i.e. 19.7% of the average current. The standard deviation obtained
including data from both cable samples 3 and 4 is on a similar level at
18.8% of the overall average quench current. The difference between
Sample 3 and Sample 4 average currents is about 50% larger than the
difference between maximum and minimum quench currents in \[4\].
Consistently with \[4\], there appears to be a flat ramp rate dependency
on the quench current.

It is interesting to notice that the difference between maximum and
minimum quench currents in the cos-theta dipole models were on the same
level as in Samples 3 and 4. Considering for the sake of homogeneity
only coil ramp rates of 20 A/s, at 4.5 K HFDA02 had a quench current
difference of 2,350 A, HFDA03 of 1,450 A, and HFDA04 of 1,850 A. Fig. 6
shows a comparison of quench currents at 4.5 K as a function of cable
ramp rate between Samples 3 and 4, and HFDA03b \[5\] and HFDA04 \[6\],
which were fabricated out of cable made of the same MJR1 strand (OST
billets 131, and 132) and heat treated with the same thermal cycle. A
transformer ratio of 35 was used to calculate current ramp rate in the
sample. One can see how the performance of the two cable samples
correlates well with that of HFDA03b and HFDA04. This is as more
relevant as unstable cables performance does not appear to depend on
background field \[4\]. The widths of the quench current distributions
shown in Fig. 6 cannot be compared at all ramp rates as for some ramp
rates the number of data points available is insufficient.

![](media/image5.wmf)

Fig. 5. Quench history results for two impregnated keystoned cables
(Samples 3 and 4) made of 28 x 1 mm MJR1 strands, heat treated using the
OST nominal cycle (HT B, RRR \~ 5).

![](media/image6.wmf)

**Fig. 6.** Comparison of quench currents at 4.5 K as function of cable
ramp rate between tests of Samples 3 and 4, and tests of HFDA03b \[5\]
and HFDA04 \[6\].

3.3 28 x 1 mm Keystoned MJR2 Cables

*Results*

A summary of test results for Samples 5 to 7, which are keystoned cables
made of 28 x 1 mm MJR2 strands and featuring a SS core, heat treated
using the short OST cycle (HT C, RRR \~ 50), is shown in Fig. 7. Two of
these cables were tested after impregnation, one was tested both before
and after impregnation (Sample 5). Closed markers denote reaching
maximum current without quenching, open markers represent quenches. In
the case of the non-impregnated cable (Sample 5), the sample reached
maximum current without quenching. The maximum current reached by the
sample as measured with the fast DAQ system was 27,539 A with a current
in the primary of 704 A, and a primary ramp rate of 70 A/s. However, in
the case of the impregnated cables, Samples 6 and 7, they started
quenching above currents of about 24 kA for Sample 6 and of 26 kA for
Sample 7. Sample 6 also reached a maximum current of 26,026 A without
quenching in Test No. 10 using a ramp rate of 100 A/s, and Sample 7 was
able to reach 27,859 A without quenching with a ramp rate of 186 A/s. As
the quenches occurred close to the transformer maximum current, such
high primary ramp rates had to be used to push the limits of the
transformer. Therefore from these data, information of ramp rate
dependency on the quench current cannot be inferred. Of the four quench
events of Sample 7 (open triangles in Fig. 7), all using a ramp rate of
186 A/s, three occurred during secondary current decay, after the sample
had reached its maximum current without quenching. However, Sample 5
after impregnation (Sample 5a) always showed quench, with an average
quench current of 21,029 A and a width (stdev) of 771 A. The average
quench current including all tests of the three impregnated samples
would be 23,104 A with a width (stdev) of 2,565 A. Details of these
tests are reported in Tables VIII to XI and Figs. 19 to 22.

*Discussion*

The first observation to be made is that these MJR2 cables, which are
made of strands very similar to those used in the MJR1 cables, show a
lot better quench current performance. This was first observed for the
non-impregnated Sample 5 on March 25, 2004, and confirmed for the
impregnated Sample 6 on April 15, 2004. Even cos-theta dipole mirror
HFDM02, which was fabricated out of cable made of the same MJR2 strand
(OST billets 187, and 190), featured an average quench current at 4.5 K
of only 11,485 A 507 A, including all ramp rates. A major difference
between the MJR1 samples and HFDM02 on one side, and these MJR2 samples
on the other is the RRR, which was measured to be 5 in the MJR1 samples,
6 in HFDM02, and about 50 in the MJR2 samples. These data represent a
strong experimental evidence of the very important effect of the RRR in
the instability phenomenon.

These data show also that the current stability range of the MJR2
samples is smaller than for the PIT samples. In a set of three
impregnated cables, there was one (Sample 5a) that featured quench
currents as measured with the fast DAQ between 20,146 A and 22,613 A.
This was useful to predict SR02 performance, which was limited at 20,200
A despite a 25,500 A short sample limit as calculated from the critical
current of witness samples. For Sample 5a, the quench current spread is
3.7%. Including all ramp rates, for this sample the 2,467 A difference
between maximum and minimum quench currents is 11.7% of the average
current. For Sample 5a, quench currents do not depend on ramp rate. The
standard deviation obtained including data from all tests of the three
impregnated samples is 11.1% of the overall average quench current. More
PIT samples need to be tested to confirm their better performance, but
this would certainly be consistent with these strands having both a
lower deff and a larger RRR. A lot more statistics is necessary to try
and quantifying their separate effects.

![](media/image7.wmf)Fig. 7. Summary of test results for three keystoned
cables (Samples 5 to 7) made of 28 x 1 mm MJR2 strands and featuring a
SS core, heat treated using the OST short cycle (HT C, RRR \~ 50). Two
of these cables were tested impregnated, one was tested both before
(Sample 5) and after (Sample 5a) impregnation. Closed markers denote
reaching maximum current without quenching, open markers represent
quenches.

3.4 41 x 0.7 mm Rectangular MJR3 Cables

*Results*

A summary of test results for Samples 8 to 11, which are rectangular
cables made of 41 x 0.7 mm MJR3 strands, heat treated using the nominal
OST cycle (HT B, RRR \~ 5), is shown in Fig. 8. One of these cables was
tested only non-impregnated, two after impregnation, and one before and
after impregnation (Sample 8). As the cables were heat treated on a
spool, to be used in the React & Wind technique, they are more prone to
damage. In the case of the non-impregnated cables (Samples 8 and 9),
after some training the samples reached currents between \~12.5 kA and
\~18.9 kA before quenching. The maximum quench current for Sample 8 was
18,862 A, which was obtained with a primary ramp rate of 120 A/s. After
a training phase of about 16 quenches, there was no apparent ramp rate
dependency on the quench current as can be seen in Fig. 9, where the
ramp rate dependency of the quench current is shown for all samples. In
the case of the impregnated cables (Samples 10, 11, and 8a), they
quenched at lower currents, between \~7.1 kA and \~14.6 kA. Details of
these tests are reported in Tables XII to XVI and Figs. 24 to 28.

*Discussion*

Typical widths of React & Wind quench current distributions appear to be
larger than in the Wind & React case. Aside from Sample 10, for which
there is very little statistics, the quench current width of the MJR3
cable samples goes from a minimum of 3.7% of the average quench current
for Sample 8a to 5.6% of the average quench current for Sample 9, to
7.6% of the average quench current for Sample 11 to a maximum of 10.6%
of the average quench current for Sample 8.

Fig. 8 compares the quench current performance of racetrack models
HFDB02 \[7\] and HFDB03 \[8\], which were made of the same cables as the
MJR3 samples, with the quench current performance of the latter. The
band delimited by the two red lines envelopes the quench currents of
racetrack models HFDB02 and HFDB03 obtained at 4.5K at all ramp rates.
It can be seen as there is some consistency between the racetracks test
results and the results associated to the impregnated cable samples.

![](media/image8.wmf)

Fig. 8. Quench history results for four rectangular cables (Samples 8 to
11, and 8a) made of 41 x 0.7 mm MJR3 strands, heat treated using the OST
nominal cycle (HT B, RRR \~ 5). One of these cables was tested only
non-impregnated, two after impregnation, and one was tested both before
(Sample 8) and after (Sample 8a) impregnation. The band delimited by the
two red lines envelopes the quench currents of racetrack models HFDB02
\[7\] and HFDB03 \[8\] obtained at 4.5K at all ramp rates.

![](media/image9.wmf)

Fig. 9. Ramp rate dependency of quench current for four rectangular
cables (Samples 8 to 11, and 8a) made of 41 x 0.7 mm MJR3 strands, heat
treated using the OST nominal cycle (HT B, RRR \~ 5). One of these
cables was tested only non-impregnated, two after impregnation, and one
was tested both before (Sample 8) and after (Sample 8a) impregnation.

######## SUMMARY

Since there are indications that cable instability might have a flat
dependence on field, at least in the lower field range, cable tests at
self-field using a SC transformer are proving to be extremely useful to
gather large statistics at very low costs. With this first run of
thirteen tested cables, substantial insight has been collected on the
effect of various parameters on the instability phenomenon. First of
all, that a RRR of 50 can improve average quench current by nearly a
factor of 2 with respect to a RRR of 5. Then that the insulation effect
of impregnation could also depend on RRR, as for instance average quench
current degradation was about double for a set of impregnated cables
having a RRR of 5 than for a set having a RRR of 50, with respect to the
average quench current of their non-impregnated versions. More
statistics is needed to confirm these first observations, and to
quantify the effect of RRR for the various Nb~3~Sn technologies.

**APPENDIX**

![](media/image10.wmf)

**Fig. 10.** Load line of the transformer secondary winding to evaluate
self-field for each test.

![](media/image11.png){width="6.124305555555556in"
height="2.1104166666666666in"}

**Fig. 11.** Voltage tap schematic used for Samples 1, 3, and 5.

![](media/image12.png){width="6.11875in" height="2.6527777777777777in"}

**Fig. 12.** Voltage tap schematic used for a first run on Samples 2.

![](media/image13.png){width="6.102777777777778in" height="2.15625in"}

**Fig. 13.** Voltage tap schematic used for the second run on Sample 2,
and for Samples 4, and 6 to 11.

![](media/image14.png){width="6.095833333333333in" height="2.71875in"}

**Fig. 14.** Voltage tap schematic used for Sample 5a.

**Table IV**. Transformer parameters and splice resistance during Sample
1 test run.

  -------- --------------- ------- --------- ------- ----------- ------- ----------
  **Test   **EVENT**       **I1,   **I2      **I2    **I2 Fast   **I1    **R
  No.**                    A**     drift,    Fast    DAQ drift,  ramp    Splices,
                                   A**       DAQ,    A**         rate,   n**
                                             A**                 A/s**   

  1        Primary Quench  630     \-        \-      \-          \-      

  2        NO QUENCH       645     21767             21767 +30   20      1.446

  3        NO QUENCH       679     22159             22061+400   20      1.467

  4        Primary Quench  707     \-        \-      \-          \-      

  5        Primary Quench  704     \-        \-      \-          \-      

  6        NO QUENCH       701     23332             23332 +30   20      1.401

  7        Primary Quench  711     \-        \-      \-          \-      

  8        NO QUENCH       701     22129             2219+30     20      1.387

  9        Primary Quench  633     \-        \-      \-          \-      

  10       Primary Quench  600     \-        \-      \-          \-      

  11       Primary Quench  705     \-        \-      \-          \-      

  12       Primary Quench  629     \-        \-      \-          \-      

  13       NO QUENCH       641     20144             20144+30    20      1.428

  14       Primary Quench  692     \-        \-      \-          \-      
  -------- --------------- ------- --------- ------- ----------- ------- ----------

> NOTE: The column "I2 drift" is I~2~ as measured by the slow
> acquisition system after drift correction. The column "I2 Fast DAQ" is
> I~2~ as acquired by the fast DAQ system. The column "I2 Fast DAQ
> drift" is I~2~ as acquired by the fast DAQ system and corrected for
> the drift.

**Table V**. Transformer parameters and splice resistance during Sample
2 test runs.

  ---------- ------------- ------- -------- ------- ------------ ------- ---------- ------------
  **Test     **EVENT**     **I1,   **I2     **I2    **I2 Fast    **I1    **R        **R Splices
  No.**                    A**     drift,   Fast    DAQ drift,   ramp    Splices,   (I2=5000),
                                   A**      DAQ,    A**          rate,   n**        n**
                                            A**                  A/s**              

  **FIRST                                                                           
  RUN**                                                                             

  1          NO QUENCH     682     22463            22463+100    20                  

  2          NO QUENCH     700     24105            24105+400    40      1.55       1.15

  3          Primary       740     \-       \-      \-           \-                  
             Quench                                                                 

  4          Primary       780     \-       \-      \-           5                   
             Quench                                                                 

  5          Primary       722     \-       \-      \-           \-                  
             Quench                                                                 

  6          QUENCH        722     24120    \-      24120+2200   60                  

  7          NO QUENCH     722     24450    24500   24824        30      1.72       1.15

  8          NO QUENCH     723     25129    25410   25571        40                  

  9          NO QUENCH     723     25740    26370   26130        60                  

  10         Primary       735     \-       \-      \-           \-                  
             Quench                                                                 

  11         NO QUENCH     724     25531    26711   26708        100                 

  12         NO QUENCH     723     25596    25911   26019        60      1.83       1.24

  13         QUENCH        726     22184    26450   26600        120                 

  14         QUENCH        726     19145    20234   20384        120                 

  15         Primary or    665     \-       \-      \-           120                
             Secondary                                                              
             Quench                                                                 

  16         Primary       725     \-       \-      \-           1                   
             Quench                                                                 

  17         QUENCH        725     17503    19370   19370        60                  

  18         NO QUENCH     725     14383    15211   15205        20      5.29       4.35

  **SECOND                                                                          
  RUN**                                                                             

  19         Primary       724     \-       \-      \-           \-                  
             Quench                                                                 

  20         NO QUENCH     703     23625    23810   24039        35      1.71        

  21         NO QUENCH     708     24765    25156   25408        70      1.56        

  22         NO QUENCH     721     25276    25045   25562        60      1.63        

  23         QUENCH        723     22974    25565   25627        80                  

  24         NO QUENCH     747     25048                         80      2.21        

  25         NO QUENCH     768     25687    26457   26243        78      2.23        

  26         Primary       720     \-       \-      \-           \-                  
             Quench                                                                 

  27         Primary       764     \-       \-      \-           \-                  
             Quench                                                                 

  28         NO QUENCH     730     25086    25570   25671        120                 

  29         NO QUENCH     756     26153    26332   26623        150                 

  30         Primary       720     \-       \-      \-           \-                  
             Quench                                                                 

  31         NO QUENCH     725     23930    24611   24510        60                  

  32         NO QUENCH     700     24369            24369+400    230                 

  33         Primary       730     \-       \-      \-           \-                  
             Quench                                                                 

  34         NO QUENCH     726     25437    25646   25881        240     2.39        
  ---------- ------------- ------- -------- ------- ------------ ------- ---------- ------------

**Table VI**. Transformer parameters and splice resistance during Sample
3 test run.

  -------- ------------- ------- --------- ------- ----------- ------- ----------
  **Test   **EVENT**     **I1,   **I2      **I2    **I2 Fast   **I1    **R
  No.**                  A**     drift,    Fast    DAQ drift,  ramp    Splices,
                                 A**       DAQ,    A**         rate,   n**
                                           A**                 A/s**   

  1        QUENCH        700     13925             13925 + 600 20       

  2        NO DATA       \-      \-        \-      \-          \-       

  3        Primary or    519     \-        \-      \-          \-      
           Secondary                                                   
           Quench                                                      

  4        NO DATA       \-      \-        \-      \-          \-       

  5        QUENCH        680     14389     14330   15049       20       

  6        QUENCH        700     13822     13815   14361       20       

  7        QUENCH        660     14340     14550   15069       20       

  8        QUENCH        680     14892     14670   15414       20       

  9        QUENCH        660     12854     12744   13281       20       

  10       QUENCH        640     13909     14220   14805       20       

  11       QUENCH        680     14400     14504   15083       20       

  12       QUENCH        660     14511     14433   14952       20       

  13       QUENCH        800     13023     13276   13904       20       

  14       QUENCH        660     14000     14200   14857       20       

  15       QUENCH        660     13577     13800   14409       20       

  16       QUENCH        600     14928     15221   15828       20       

  17       QUENCH        600     13497     13180   13988       20       

  18       QUENCH        680     14452     14210   14864       20       

  19       QUENCH        560     14430     14440   14975       20       

  21       QUENCH        700     13924     14100   14495       40       

  22       QUENCH        660     12838     13960   14326       40       
  -------- ------------- ------- --------- ------- ----------- ------- ----------

**Table VII**. Transformer parameters and splice resistance during
Sample 4 test run.

  -------- ------------ -------- -------- --------- --------- -------- ----------
  **Test   **EVENT**    **I1,    **I2     **I2 Fast **I2 Fast **I1     **R
  No.**                 A**      drift,   DAQ, A**  DAQ       ramp     Splices,
                                 A**                drift,    rate,    n**
                                                    A**       A/s**    

  1        QUENCH       571      9726               9726 +    20        
                                                    800                

  2        QUENCH       532      9747     10220     10559     20        

  3        QUENCH       467      8835     9500      9589      15        

  4        QUENCH       348      9868     10295     10466     15        

  5        QUENCH       406      8899     9450      9572      15        

  6        QUENCH       424      8912     9661      9914      15        

  7        QUENCH       401      9285      -        9285 +    10        
                                                    400                

  8        QUENCH       360      8935     9100      10042     15        

  9        QUENCH       410      10255    10955     11157     15        

  10       QUENCH       394      9371     10210     10372     15        

  11       QUENCH       378      8927     9240      9500      15        

  12       QUENCH       360      9406     9970      10207     15        

  13       QUENCH       391      10271    10850     11085     15        

  14       QUENCH       365      9386     10288     10405     15        

  15       QUENCH       407      9411     10060     10200     15        

  16       QUENCH       395      9816     9893      10095     15        

  17       QUENCH       352      9110     9477      9765      15        

  18       QUENCH       362      8676     9850      10051     30        

  19       QUENCH       346      9767     10323     10531     30        

  20       QUENCH       361      8845     9750      10017     60        

  21       QUENCH       361      6554     9981      10225     60        

  22       QUENCH       391      4482     10103     10300     120       

  23       QUENCH       400      4169     9854      10032     120       
  -------- ------------ -------- -------- --------- --------- -------- ----------

**Table VIII**. Transformer parameters and splice resistance during
Sample 5 test run.

  -------- ---------------- ------- -------- ------- --------- -------- ----------
  **Test   **EVENT**        **I1,   **I2     **I2    **I2 Fast **I1     **R
  No.**                     A**     drift,   Fast    DAQ       ramp     Splices,
                                    A**      DAQ,    drift,    rate,    n**
                                             A**     A**       A/s**    

  1        Primary Quench   640     \-       \-      \-        \-        

  2        Primary Quench   630     \-       \-      \-        \-        

  3        File not saved   612                                10        

  4        Primary Quench   621     \-       \-      \-        \-        

  5        NO QUENCH        613     21812    22576   22474     20        

  6        NO QUENCH        641     23333    23407   23607     20        

  7        NO QUENCH        665     23867    24100   24350     20        

  8        Primary Quench   685     \-       \-      \-        \-        

  9        NO QUENCH        680     25853    25970   26131     40        

  10       NO QUENCH        683     25511    26766   26866     60        

  11       NO QUENCH        690     25318    25643   26341     50        

  12       Primary Quench   712     \-       \-      \-        \-        

  13       NO QUENCH        704     27048    27207   27539     70        

  14       NO QUENCH        703     27155    27205   27520     100       

  15       Primary or       587                                100      
           Secondary                                                    
           Natural Quench                                               

  16       Primary Quench   594     \-       \-      \-        \-        

  17       Primary Quench   649     \-       \-      \-        \-        

  18       Primary Quench   693     \-       \-      \-        \-        

  19       NO QUENCH        704     24951    25040   25259     100       

  20       NO QUENCH        705     24600    24680   24983     70        
  -------- ---------------- ------- -------- ------- --------- -------- ----------

**Table IX. Transformer parameters and splice resistance during Sample
5a test run.**

  -------- -------------- ------- ------- -------- ------- --------- -------- -------------
  **Test   **EVENT**      **I1,   **I2,   **I2     **I2    **I2 Fast **I1     **R Splice
  No.**                   A**     A**     drift,   Fast    DAQ       ramp     nL2=0.23H**
                                          A**      DAQ,    drift,    rate,    
                                                   A**     A**       A/s**    

  1        QUENCH         706     19130   18112            18112     50        
                                                           +1750              

  2        QUENCH         706     19235   19647    21370   21782     50        

  3        QUENCH         617     18161   18690    20173   20702     30        

  4        Standard test  560     17313   17680                               1.58
           Splice                                                             

  5        Primary Quench 690     3000    \-       \-      \-        \-        

  6        Primary Quench 689     3588    \-       \-      \-        \-        

  7        Primary Quench 687     800     \-       \-      \-        \-        

  8        QUENCH         633     19378   19782    20769   21173     30        

  9        QUENCH         662     17952   19507    18592   20146     15        

  10       QUENCH         690     20011   20227    20011   20227     15        

  11       QUENCH         694     19531   19579    20126   20174     15        

  12       QUENCH         701     19637   19895    20345   20604     15        

  13       Primary Quench 705     647                                          

  14       QUENCH         699     19347   19843    19786   20282     15        

  15       Primary Quench 645     5739                                         

  16       Standard test  695     20663   20742                               1.74
           Splice                                                             

  17       QUENCH         697     18588   18732    20380   20524     30        

  18       QUENCH         695     19312   19512    21530   21730     60        

  19       QUENCH         681     19748   19549    21965   21766     60        

  20       QUENCH         707     18399   18618    22000   22219     100       

  21       Primary Quench 660     1013                                         

  22       NO Quench      706     22063   22271    22822   23030     100       

           QUENCH                 22063   22271    22405   22613     100       

  23       QUENCH         707     20135   20262    20764   20891     20        

  24       QUENCH         701     19926   20189    20558   20821     20        

  25       QUENCH         701     18416   18645    20583   20812     100       

  26       QUENCH         601     18612   18804            18804 +   100       
                                                           3500               

  27       Standard test  620     19235   19442                               1.61
           Splice                                                             
  -------- -------------- ------- ------- -------- ------- --------- -------- -------------

**Table X**. Transformer parameters and splice resistance during Sample
6 test run.

  -------- ------------- ------- -------- -------- ------------ ------- ----------
  **Test   **EVENT**     **I1,   **I2     **I2     **I2 Fast    **I1    **R
  No.**                  A**     drift,   Fast     DAQ drift,   ramp    Splices,
                                 A**      DAQ, A** A**          rate,   n**
                                                                A/s**   

  1        NO QUENCH     500     16880    16950    17630        15      1.484

  2        NO QUENCH     629     20892                          15      1.556

  3        Primary       670     \-       \-       \-           \-       
           Quench                                                       

  4        NO QUENCH     637     22226    22395    22746        30      1.617

  5        NO QUENCH     680     24256    24790    24813        40      1.612

  6        Primary       700     \-       \-       \-           \-       
           Quench                                                       

  7        QUENCH        685     22579    24140    23899        85       

  8        Primary       680     \-       \-       \-           \-       
           Quench                                                       

  9        NO QUENCH     689     25051    25290    25510        85      1.641

  10       NO QUENCH     702     25757    25491    26026        100     1.620

  11       QUENCH        725     22857    25654    25916        120      

  12       QUENCH        725     22795             22794+4000   120      

  13       Primary       755     \-       \-       \-           \-       
           Quench                                                       

  14       Primary       780     \-       \-       \-           \-       
           Quench                                                       

  15       QUENCH        729     22786    26237    26304        120      

  16       Primary       620     \-       \-       \-           \-       
           Quench                                                       

  17       QUENCH        720     22791             22791+4000   120      

  18       Primary       725     \-       \-       \-           \-       
           Quench                                                       

  19       QUENCH        725     22722    25092    25192        120      

  20       Primary       709     \-       \-       \-           \-       
           Quench                                                       

  21       QUENCH        720     22811    26000    26016        120      

  22       Primary       689     \-       \-       \-           \-       
           Quench                                                       

  23       QUENCH        729     22797    25950    25792        120      

  24       QUENCH        725     23583    25182    25171        90       

  25       Primary       690     \-       \-       \-           \-       
           Quench                                                       

  26       QUENCH        725     23621    25979    25720        90       

  27       Primary       680     \-       \-       \-           \-       
           Quench                                                       
  -------- ------------- ------- -------- -------- ------------ ------- ----------

**Table XI**. Transformer parameters and splice resistance during Sample
7 test run.

  -------- -------------- ------- -------- -------- --------- --------- ----------
  **Test   **EVENT**      **I1,   **I2     **I2     **I2 Fast **I1 ramp **R
  No.**                   A**     drift,   Fast     DAQ       rate,     Splices,
                                  A**      DAQ, A** drift,    A/s**     n**
                                                    A**                 

  1        Primary Quench 637     \-       \-       \-        \-         

  2        NO QUENCH      676     20800                       15         

  3        Primary Quench 709     \-       \-       \-        \-         

  4        Primary Quench 700     \-       \-       \-        \-         

  5        NO QUENCH      695     23553    23746    23864     30        1.70

  6        Primary Quench 700     \-       \-       \-        \-         

  7        NO QUENCH      685     23808    24278    24278     40        1.79

  8        NO QUENCH      685     23269    24330    24670     80         

  9        NO QUENCH      705     25214    25122    25494     70         

  10       NO QUENCH      711     25597    25828    26272     100        

  11       NO QUENCH      724     26442    26601    26875     120        

  12       NO QUENCH      722     26785    26895    27119     180        

  13       Primary Quench 720     \-       \-       \-        \-         

  14       NO QUENCH      739     27274    27419    27619     184       1.90

  15       QUENCH         744     21544    26240    26420     186        

  16       Primary Quench 670     \-       \-       \-        \-         

  17       Primary Quench 710     \-       \-       \-        \-         

  18       NO QUENCH      746     27498    27831    27859     186       1.94

  19       Primary Quench 706     \-       \-       \-        \-         

  20       Primary Quench 700     \-       \-       \-        \-         

  21       Primary Quench 763     \-       \-       \-        \-         

  22       Low Helium             \-       \-       \-        \-         

  23       NO QUENCH      744     27439    27660    27720     186        

           QUENCH                 27008    26811    26871     186        

  24       Primary Quench 700     \-       \-       \-        \-         

  25       Primary Quench 710     \-       \-       \-        \-         

  26       NO QUENCH      708     25454    25900    26007     100        

  27       Primary Quench 722     \-       \-       \-        \-         

  28       Primary Quench 725     \-       \-       \-        \-         

  29       NO QUENCH      716     25922    26070    26238     102        

  30       NO QUENCH      746     27402    27630    27771     186        

           QUENCH                 27402    27000    27141     186        

  31       Primary Quench 710     \-       \-       \-        \-         

  32       Primary Quench 702     \-       \-       \-        \-         

  33       Primary Quench 746     \-       \-       \-        \-         

  34       NO QUENCH      722     26543    26934    26876     120        

  35       Primary Quench 744     \-       \-       \-        \-         

  36       Primary Quench 728     \-       \-       \-        \-         

  37       NO QUENCH      745     27185    27228    27510     186        

           QUENCH                 26031    25720    26004     186        

  38       NO QUENCH      700     24741    24646    25073     100       1.77
  -------- -------------- ------- -------- -------- --------- --------- ----------

**Table XII**. Transformer parameters and splice resistance during
Sample 8 test run.

  -------- ------------ ------- --------- --------- ---------- -------- ----------
  **Test   **EVENT**    **I1,   **I2      **I2 Fast **I2 Fast  **I1     **R
  No.**                 A**     drift,    DAQ, A**  DAQ drift, ramp     Splices,
                                A**                 A**        rate,    n**
                                                               A/s**    

  1        QUENCH       626     10294     11180     10879      15        

  2        QUENCH       352     11591     12267     12536      15        

  3        NO QUENCH    333     12649                                   1.353

  4        NO QUENCH    372     13491                                   1.596

  5        QUENCH       457     14610     14938     15093      15        

  6        NO QUENCH    432     15426                                   1.536

  7        QUENCH       512     15961     16270     16594      15        

  8        QUENCH       533     16446     16900     17208      15        

  9        QUENCH       543     15931     16600     17008      15        

  10       QUENCH       516     15999     16490     16690      15        

  11       QUENCH       511     16054     16490     16715      15        

  12       QUENCH       577     16977     17681     18050      15        

  13       NO QUENCH    436     15475                                   1.533

  14       QUENCH       526     13996                          5         

  15       QUENCH       589     14819     14624     15144      5         

  16       Primary      630     \-        \-        \-         \-        
           Quench                                                       

  17       QUENCH       626     15150     15250     15382      5         

  18       QUENCH       647     15528     15208     15727      5         

  19       QUENCH       560     16472     17190     17495      15        

  20       QUENCH       571     12808     14255     14561      30        

  21       QUENCH       563     10551     12332     12687      30        

  22       QUENCH       473     13976     16545     16746      50        

  23       QUENCH       541     15853                          50        

  24       QUENCH       525     13930     17707     17887      50        

  25       QUENCH       561     16181     18181     18357      80        

  26       QUENCH       582     16028     18500     18752      80        

  27       QUENCH       520     15059     18500     18749      120       

  28       QUENCH       527     14870     18028     18200      120       

  29       QUENCH       580     14537     18700     18862      120       

  30       QUENCH       600     17405     17789     18148      15        

  31       QUENCH       513     16062     16632     16952      15        

  32       QUENCH       525     16380     18083     18307      30        

  33       QUENCH       451     13659                          15        

  34       NO QUENCH    431     14629                                   1.501
  -------- ------------ ------- --------- --------- ---------- -------- ----------

**Table XIII**. Transformer parameters and splice resistance during
Sample 8a test run.

  -------- -------------- ------- ---------- -------- ------- --------- ------- -------------
  **Test   **EVENT**      **I1,   **I2,A**   **I2     **I2    **I2 Fast **I1    **R Splice
  No.**                   A**                drift,   Fast    DAQ       ramp    nL2=0.23H**
                                             A**      DAQ,    drift,    rate,   
                                                      A**     A**       A/s**   

  1        QUENCH         722     13032      13135            13135 +   15       
                                                              500               

  2        QUENCH         427     13577      13634    14500   14557     15       

  3        QUENCH         473     12877      12760    13660   13543     15       

  4        QUENCH         551     12890      12749    13630   13489     15       

  5        QUENCH         465     12248      12782    12900   13433     15       

  6        QUENCH         545     13616      13671    14285   14340     15       

  7        QUENCH         481     12819      12819    13580   13580     15       

  8        Standard test  317     10738      10890                              1.21
           Splice                                                               

  9        QUENCH         512     12815      12815    13430   13430     10       

  10       QUENCH         555     12732      13010    13260   13537     10       

  11       QUENCH         472     11276      11085    13490   13299     30       

  12       QUENCH         460     11044      11010    13000   12965     30      1.44

  13       QUENCH         421     9232       8968     13050   12787     60       

  14       QUENCH         436     12813      12868            12868 +   10       
                                                              350               

  15       QUENCH         512     12871      13059    13557   13745     10       

  16       QUENCH         504     7436       7601     12645   12810     100      

  17       QUENCH         466     12728      12785    13320   13377     15       

  18       Standard test  320     10626      10825                              1.19
           Splice                                                               
  -------- -------------- ------- ---------- -------- ------- --------- ------- -------------

**Table XIV. Transformer parameters and splice resistance during Sample
9 test run.**

  -------- -------------- ------- ---------- -------- ------- --------- ------- -------------
  **Test   **EVENT**      **I1,   **I2,A**   **I2     **I2    **I2 Fast **I1    **R Splice
  No.**                   A**                drift,   Fast    DAQ       ramp    nL2=0.23H**
                                             A**      DAQ,    drift,    rate,   
                                                      A**     A**       A/s**   

  1        QUENCH         662     13376      12720    14500   13844     15       

  2        QUENCH         424     13012      12944    14000   13932     15      ** **

  3        QUENCH         437     12759      12411    13700   13352     15      **1.57**

  4        Primary or     400     9326                                  15      
           Secondary                                                            
           Quench                                                               

  5        NO Quench      378     13800      13973                      15      1.77

  6        QUENCH         444     12836      12863            12863 +   15      ** **
                                                              650               

  7        QUENCH         423     13968      13777    14770   14579     15      ** **

  8        QUENCH         405     13525      13340    14540   14355     15       

  9        QUENCH         422     13186      13048    14200   14062     15       

  10       QUENCH         406     13535      13389    14470   14324     15       

  11       QUENCH         408     13115      12999    14050   13934     15       

  12       QUENCH         416     13039      12880    13840   13681     15      ** **

  13       Primary or     309     11450                                         
           Secondary                                                            
           Quench                                                               

  14       QUENCH         423     12201      12340    12970   13109     15      **1.52**

  15       QUENCH         426     11870      11874    13740   13744     30       

  16       QUENCH         434     12952      12913    14855   14817     30       

  17       QUENCH         453     12658      12114    16190   15646     60       

  18       QUENCH         435     12017      11934    15700   15618     60      ** **

  19       Primary or     423     9643                                          
           Secondary                                                            
           Quench                                                               

  20       QUENCH         423     12259      12094    14500   14335     100      

  21       QUENCH         402     12037      12037    15240   15240     100      

  22       QUENCH         443     12439      12482    13190   13234     15       

  23       Primary or     316     10498                                         
           Secondary                                                            
           Quench                                                               

  24       QUENCH         487     13301      13411    14145   14254     15      **1.54**
  -------- -------------- ------- ---------- -------- ------- --------- ------- -------------

**Table XV**. Transformer parameters and splice resistance during Sample
10 test run.

  -------- ------------- ------- -------- -------- ---------- --------- ----------
  **Test   **EVENT**     **I1,   **I2     **I2     **I2 Fast  **I1 ramp **R
  No.**                  A**     drift,   Fast     DAQ drift, rate,     Splices,
                                 A**      DAQ, A** A**        A/s**     n**

  1        QUENCH        650     6796              6796 + 600 15         

  2        QUENCH        414     6637     7343     7467       15         

  3        QUENCH        245     6844     7415     7483       15         

  4        NO QUENCH     202     6875                                   1.679

  5        NO QUENCH     227     6811                                    

  6        QUENCH        235     6827     7478     7531       15         

  7        NO QUENCH     221     7116                         15        1.955

  8        QUENCH        270     6822     7367     7502       15         

  9        QUENCH        311     6979     7060     7263       5          

  10       NO QUENCH     341     6096                         2          

  11       NO QUENCH     450     6696                         2          

  12       QUENCH        390     6901              6901+200   5          

  13       QUENCH        320     6826     6850     7142       5          

  14       QUENCH        311     6774     6780     7098       5          
  -------- ------------- ------- -------- -------- ---------- --------- ----------

**Table XVI**. Transformer parameters and splice resistance during
Sample 11 test run.

  -------- ------------ ------- -------- ---------- ---------- --------- ----------
  **Test   **EVENT**    **I1,   **I2     **I2 Fast  **I2 Fast  **I1 ramp **R
  No.**                 A**     drift,   DAQ, A**   DAQ drift, rate,     Splices,
                                A**                 A**        A/s**     n**

  1        QUENCH       482     7302     8082       8255       15         

  2        QUENCH       305     7362     8272       8443       15         

  3        QUENCH       332     7891     8520       8642       15         

  4        QUENCH       256     7317     8180       8274       15         

  5        NO QUENCH    230     7430                                     1.364

  6        QUENCH       287     7365                           15         

  7        QUENCH       257     7349     8090       8220       15         

  8        QUENCH       259     7841     8512       8648       15         

  9        QUENCH       242     7863     8447       8576       15         

  10       QUENCH       257     7313     8260       8396       15         

  11       QUENCH       241     7854     8709       8844       15         

  12       QUENCH       321     8804     9200       9101       5          

  13       QUENCH       335     9232     9340       9521       5          

  14       QUENCH       326     8768     8800       9031       5          

  15       QUENCH       306     5721     7470       7611       30         

  16       QUENCH       362     5766     7617       7567       30         

  17       File Not                      7499                             
           Saved                                                         

  18       QUENCH       302     5694     7665       7794       30         

  19       QUENCH       251     4680     7300       7407       60         

  20       QUENCH       288     4462     7330       7420       60         

  21       QUENCH       247     4566     7800       7640       120        

  22       QUENCH       256     4629     7317       7343       120        

  23       QUENCH       252     7173     8168       8203       15         

  24       QUENCH       347     8695     8855       9004       5          

  25       NO QUENCH    212     7408                                     1.365
  -------- ------------ ------- -------- ---------- ---------- --------- ----------

![](media/image15.wmf)

**Fig. 15.** Test results for Sample 1.

![](media/image16.wmf)

**Fig. 16.** Test results for Sample 2. Closed markers denote reaching
maximum current without quenching, open markers represent quenches.

![](media/image17.wmf)

**Fig. 17**. Test results for Sample 3.

![](media/image18.wmf)

**Fig. 18.** Test results for Sample 4.

![](media/image19.wmf)

**Fig. 19**. Test results for Sample 5.

![](media/image20.wmf)

**Fig. 20.** Test results for Sample 5a. Closed markers represent
quenches, open markers denote reaching maximum current without
quenching.

![](media/image21.wmf)

**Fig. 21.** Test results for Sample 6. Closed markers represent
quenches, open markers denote reaching maximum current without
quenching.

![](media/image22.wmf)

**Fig. 22.** Test results for Sample 7. Open markers represent quenches,
closed markers denote reaching maximum current without quenching.

![](media/image23.wmf)

**Fig. 23.** Test results for Sample 8.

![](media/image24.wmf)

**Fig. 24.** Test results for Sample 8a.

![](media/image25.wmf)

**Fig. 25.** Test results for Sample 9.

![](media/image26.wmf)

**Fig. 26.** Test results for Sample 10.

![](media/image27.wmf)

**Fig. 27.** Test results for Sample 11.

![](media/image28.png){width="5.928472222222222in"
height="3.888888888888889in"}

![](media/image29.png){width="5.946527777777778in" height="3.90625in"}

**Fig. 28.** Voltage signal pattern for Sample 2/ Test 13. Bottom is a
close-up.

![](media/image30.png){width="5.867361111111111in"
height="3.848611111111111in"}

![](media/image31.png){width="5.840972222222222in" height="3.83125in"}

**Fig. 29.** Voltage signal pattern for Sample 2/ Test 14. Bottom is a
close-up.

![](media/image32.png){width="5.831944444444445in" height="3.83125in"}

![](media/image33.png){width="5.831944444444445in" height="3.83125in"}

**Fig. 30.** Voltage signal pattern for Sample 2/ Test 17. Bottom is a
close-up.

![](media/image34.png){width="5.840972222222222in" height="3.8375in"}

![](media/image35.png){width="5.831944444444445in" height="3.83125in"}

**Fig. 31.** Voltage signal pattern for Sample 2/ Test 23. Bottom is a
close-up.

![](media/image36.png){width="6.218055555555556in"
height="4.311805555555556in"}

**Fig. 32.** Voltage signal pattern for Sample 3/ Test 10.

![](media/image37.png){width="6.902777777777778in"
height="4.495833333333334in"}

![](media/image38.png){width="6.892361111111111in"
height="4.502083333333333in"}

**Fig. 33.** Voltage signal pattern for Sample 3/ Test 16. Bottom is a
close-up.

![](media/image39.png){width="6.209722222222222in"
height="4.073611111111111in"}

**Fig. 34.** Voltage signal pattern for Sample 4/ Test 8.

![](media/image40.png){width="6.209722222222222in"
height="4.073611111111111in"}

**Fig. 35.** Voltage signal pattern for Sample 4/ Test 9.

![](media/image41.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 36.** Voltage signal pattern for Sample 5a/ Test 18.

![](media/image42.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 37.** Voltage signal pattern for Sample 5a/ Test 22.

![](media/image43.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 38.** Voltage signal pattern for Sample 6/ Test 7.

![](media/image44.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 39.** Voltage signal pattern for Sample 6/ Test 15.

![](media/image45.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 40.** Voltage signal pattern for Sample 6/ Test 23.

![](media/image46.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 41.** Voltage signal pattern for Sample 7/ Test 23.

![](media/image47.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 42.** Voltage signal pattern for Sample 7/ Test 30.

![](media/image48.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 43.** Voltage signal pattern for Sample 8/ Test 1.

![](media/image49.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 44.** Voltage signal pattern for Sample 8/ Test 10.

![](media/image50.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 45.** Voltage signal pattern for Sample 8a/ Test 11.

![](media/image51.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 46.** Voltage signal pattern for Sample 8a/ Test 12.

![](media/image52.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 47.** Voltage signal pattern for Sample 9/ Test 17.

![](media/image53.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 48.** Voltage signal pattern for Sample 9/ Test 18.

![](media/image54.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 49.** Voltage signal pattern for Sample 10/ Test 8.

![](media/image55.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 50.** Voltage signal pattern for Sample 10/ Test 14.

![](media/image56.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 51.** Voltage signal pattern for Sample 11/ Test 1.

![](media/image57.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 52.** Voltage signal pattern for Sample 11/ Test 7.

![](media/image58.png){width="6.139583333333333in"
height="4.033333333333333in"}

**Fig. 53.** Voltage signal pattern for Sample 11/ Test 15.

######## REFERENCES

\[1\] N. Andreev et al., *"An Upgraded SC Transformer to Test Rutherford
Cables at Self-field"*, FNAL TD-04-012.

\[2\] D. Turrioni, *"A Fast DAQ Solution for Transformer Tests at the
SSTF",* FNAL TD-04-011.

\[3\] B. Bordini et al., *"SR01 Test Summary Report"*, FNAL TD-04-035.

\[4\] G. Ambrosio et al., *"Test of Cables made of 1 mm OST-MJR Strand
at BNL",* FNAL TD-04-008.

\[5\] S. Fehers et al., *"HFDA-03B Test Summary"*, FNAL TD-03-040, Aug.
27, 2003.

\[6\] S. Fehers et al., *"HFDA-04 Test Summary"*, FNAL TD-02-045, Aug.
2, 2002.

\[7\] G. Ambrosio et al., *"Fabrication and Test of a Racetrack Magnet
using Pre-reacted Nb~3~Sn Cable"*, 2002 Applied Superconductivity
Conference, IEEE Transactions on Applied Superconductivity, V. 13, No.
2, June 2003, p. 1284.

\[8\] G. Ambrosio et al., *"Design Modifications, Fabrication and Test
of HFDB-03 Racetrack Magnet Wound with Pre-Reacted Nb~3~Sn Rutherford
Cable",* submitted to the Cryogenic Engineering and International
Cryogenic Materials Conference, Sept. 22-25, 2003, Alaska, for
publication on Advances in Cryogenic Engineering.