$&7(676<67(06
7DQN7\SH7UDQVIRUPHUV
7\SH36.
N9


7DQNW\SHWHVWWUDQVIRUPHUN9N9$






2

$SSOLFDWLRQ
Conventional AC test transformers are especially designed for testing objects of medium
capacitance in the factory, indoor or outdoor. These systems are particularly suited for tests
requiring stable voltage even if the load changes under voltage (heavy corona, wet & pollution
tests) or when the load is of inductive kind (inductive voltage transformers). The system duty
cycle can be freely chosen and is insured by adding radiators or forced oil-cooling to thetransformers. These systems are also suited for continuous duty, long duration tests.

8VHUEHQHILWV••••Indoor or outdoor designs with adapted bushings, suitable also for pollution tests
Large range of application and low acoustic noise level (approx. 65 dBA)
Sophisticated protection features for optimal test object & personnel protection
Possibility to use an external oil expansion vessel with Buchholz or DGPT 2 relay

4XDOLW\Haefely quality assurance complies with ISO 9001. The electronic measurement and control
devices are designed and manufactured in-house. Our many years of experience in dealing with
EMC is therefore an important asset.
The design of the test system complies with the VDE 0104 standard for optimal protection of theoperating personnel. The test system is shut down in case of over-voltage, over-current and fast
voltage transients. Damage at the fault area is minimised.

N9N9$WHVWWUDQVIRUPHU

3

%ORFNGLDJUDPRIDW\SLFDOWUDQVIRUPHUWHVWV\VWHP RSWLRQVDOVRVKRZQ 

Damping resistor

LV Protection unit

Regulatingtransformer

Power line filter

Compensating
reactorControl cables

HV test transformer

Coupling capacitor
HV divider / filter

Standard capacitor

Partial discharge
detector

Capacitance andtan delta bridge

Test object

kV

Power connections
Measuring cables

Control unit

6\VWHPFRQILJXUDWLRQThe test system includes following main components:
•
•
•
•
•
•
•

Regulating transformer
Power line filter
Compensating reactor
Test transformer
Coupling capacitor
Control system OT 247
HV and grounding connections between HV elements. Connection to test object usually notincluded.

$YDLODEOH2SWLRQV• HV filter inductance for coupling capacitor• Damping resistance• Low voltage protection unit
• Standard capacitor• Control system OT 257 instead of the OT 247• Additional HV connections• Partial Discharge detectors• Capacitance and power loss factor measuring bridges• Other devices upon request.
4)XQFWLRQRIWKHWHVWV\VWHP
The conventional tank type test transformers type PK steps up the voltage coming from theregulating transformer type STL (air insulated) or STO (oil insulated).
The controls act on the regulating transformer to adjust precisely the input voltage of thetransformer and thus the test voltage.
A compensating reactor type KDL is connected between the regulating and the test transformers
and compensates the capacitive power required for the test object. This way, the regulatingtransformer and the power line filter ratings can be kept small. It reduces also the power supply
requirements.
The voltage measurement is carried out by using a separate HV divider / coupling capacitor. It isalso possible to use the capacitive graded bushing as HV part of the divider.

6\VWHPFRPSRQHQWVVHULHV36.
These systems are usually customised designs. The table below only gives some typicalexamples. Rated voltages between 20 and 1000 kV and rated currents up to 5 A are available.
The duty cycle is also adapted to customers’ needs and is therefore not stated in below table.

     

   !"#%$&' ()* + ! , " )'  !"#%$&' -.'$ /$3"! , " )4 !05%$ 6.

$*  + , " )70!!0 , %$ -$8#%$0$" 12*#%$0$" 12*" 8

PSK 30-30

PK 30-30

STL 50---KK 50-1

PSK 70-70

PK 70-70

STL 75---

KK 100-1

PSK 90-150

PK 90-150

STL 150---

KK 100-1

PSK 100-600

PK 100-600

STL 200

KDL 800

KK 100-1

PSK 210-300

PK 210-300

STL 100

KDL 400

KK 300-1

PSK 400-1600

PK 400-1600

STO 500

KDL 2100

KK 400-1

PSK 700-1400

PK 700-1400

STO 400

KDL 2000

KK 700-1

PSK 900-900

PK 900-900

STO 300

KDL 1200

KK 900-1

Usual system duty cycle is 1 h On, 1 h OFF, 2 times per day.

5

6WDQGDUGDPELHQWFRQGLWLRQVIRUWKH$&WHVWHTXLSPHQWHeight above sea level≤ 1000 m

Relative humidity in main hall under non condensing conditions
non condensing- Temperature averaged over 24 h for H.V. components- Extreme temperatures for H.V. components- Temperature for electronic controls and measuring(equipment to operate withthe specified measuring errors)≤ 90 %
min. 0 °C, max. + 30 °C
min. - 5 °C, max. + 40 °C
min. + 15 °C, max. + 25 °C

For outdoor or pollution tests, special bushings having the required creeping distance are used,allowing higher relative humidity levels.

(OHFWULFDOOLQHGLDJUDPRIDW\SLFDOWUDQVIRUPHUWHVWV\VWHPTo test object

Damping Resistor
Coupling Capacitor
with HV Filter
High Voltage Tansformer
Compensating Reactors

Transformer
Protection Unit

Regulating Transformer
SEK
Electrical Supply from customer

Connection box
Regulator

Measuring cable

Controls
Measuring and control cable

Only main components are shown.

6

'HVFULSWLRQRIWKHWHVWV\VWHPFRPSRQHQWV5HJXODWLQJWUDQVIRUPHUW\SH67/DQG672
'HVFULSWLRQThe regulating transformer adjust the input voltage of the test
transformer practically without steps. The unit is for indoor
operation. The active part is air insulated (type STL) or oil
insulated (type STO) and built into a cubicle or tank. The
primary winding is galvanically separated from the secondary
winding. The driving motor allows a slow and a fast regulating
speed (40-240 s from 0-100 % of the voltage).
The primary breaker and secondary contactor are placed in theregulator cabinet.
The power line filter can be built-in or attached to theregulating transformer cubicle.

5HJXODWLQJWUDQVIRUPHU
W\SH6727HFKQLFDOGDWDRIWKHUHJXODWLQJWUDQVIRUPHUVHULHV67/ -.

(! 24 $ 9:0$" 2!
; $+  !)

6, '" , $".-<-=><7?

=, )@"&A!  %$ < 10$" 12*

STL 5050400

1.6 x 0.6 x 2.0

570

STL 7575

400

1.4 x 0.9 x 1.5

790

STL 100

100

400

1.7 x 0.9 x 1.5

990

STL 150150

1000

1.0 x 1.8 x 1.5

1540

STL 200

200

1000

1.2 x 2.0 x 1.7

1700

5)

7HFKQLFDOGDWDRIWKHUHJXODWLQJWUDQVIRUPHUVHULHV672 - /(! 24 $ 9:0$" 2!
; $+  !)

6, '" , $".-<-=><7?

=, )@"&A!  %$ < 10$" 12*

STO 300

300

1000

1.6 x 1.4 x 2.9

5000

STO 400

400

1000

1.6 x 1.4 x 3.0

5300

STO 500

500

1000

1.7 x 1.6 x 3.0

6400

STO 800

800

1000

1.8 x 1.7 x 3.2

8600

5)

7

3RZHUOLQHILOWHUVW\SH1/)$'HVFULSWLRQFor the reduction of line carried noise from the mains. The power line filter filters both phase andis connected to ground. The filter is either built into the cubicle of air insulated regulatingtransformers. Special arrangements are possible for big systems depending of local installation
conditions.
Their power rating is adapted to regulating transformer rated power.
Typical insertion loss per phase measured
at 50 Ω / 50 Ω, MIL-STD 220 A
in the following frequency range of>
80 dB
14 kHz...10 MHz&RPSHQVDWLQJUHDFWRUW\SH.'/
'HVFULSWLRQFor the compensation of the reactive power of capacitive test
objects.
The air insulated compensating reactor is connected between theregulating transformer and the test transformer. Therefore, thepower rating of the regulating transformer and of a possibly preconnected power filter can be kept small.
The compensating reactor includes typically 3 inductances which
can be combined to achieve up to 7 different power combinations.
The re-connection is basically done manually. Upon request(option), a remote re-connection with switches actuated from thecontrols can be offered.

7HFKQLFDOGDWDRIWKH.'/FRPSHQVDWLQJUHDFWRUVHULHV 6.

6, '" , $".-<-=><7?

&RPSHQVDWLQJUHDFWRUW\SH.'/

(! 24 $ 9:(! 2 ; $+  !)

=, )@"&A!  %$ < 10$" 12*

KDL 180180

400

1.1 x 1.2 x 1.0

550

KDL 360360

400

1.2 x 1.2 x 1.0

850

KDL 900

900

1000

1.6 x 1.3 x 1.4

1800

KDL 1800

1800

1000

2.5 x 1.3 x 1.5

3200

KDL 2800

2800

1000

2.7 x 1.4 x 1.5

4200

5)

As the compensating reactors are designed specifically to the system specification, only a few
examples are given in the above table.
8

/RZYROWDJHSURWHFWLRQGHYLFHW\SH163
'HVFULSWLRQTo prevent inadmissible high recovery over-voltages on the test transformer in case of disruptive
discharges on the test object. The low voltage protection device NSP acts by opening the power
supply and by short-circuiting of the test transformer within a few hundred microseconds. Thisavoids repetitive flash-overs in the test object.
Regulatingtransformer
STL/STO

Test transformer PK

Opening switch fordisconnecting thepower supply
Closing switch forshort-circuiting the
primary winding$&WHVWWUDQVIRUPHUW\SH3.
'HVFULSWLRQ
Test transformers are used for the temporary or continuous generation of high AC voltages. An
essential point lies in that the excitation of the low-voltage winding can be preset stepless fromzero to the desired level, the „ON" period is different for the various applications. It varies from a
one-minute to continuous duty.
The oil insulated transformer is built into a steel tank and can be used for indoor and outdoor
operation.
The windings are of layer-wound design with a high capacitive coupling between layers and turns.
This design provides a high transient voltage withstand capability in case of external breakdowns.
3ULPDU\ZLQGLQJ
The primary winding is divided into two groups for 100 % output each. When the two winding
groups are connected in parallel and the regulating transformer is set to 100 % voltage, thetransformer attains its, nominal voltage. When the two winding groups are connected in series
only 50 % of rated voltage are attained, with the same regulating transformer setting. This allows
to set lower test voltages with higher accuracy. Changing of the connection is made by switching
links.


9

+LJKYROWDJHZLQGLQJThe neutral end of the high-voltage winding is brought out insulated. The high-voltage end isconnected to the transformer bushing.

2YHUYROWDJHSURWHFWLRQSurge arresters are installed in parallel with the primary and the coupling winding to protect thetransformer against over voltages in the case of flashovers. Moreover, surge arresters are
installed between the primary winding and ground and between the coupling winding and ground.
'LHOHFWULF
The dielectric consists of paper, transformer board and mineral oil. The complete test transformer
is dried under high vacuum and heat. The oil-impregnation and oil-filling processes are also
made under vacuum. The insulating oil is Shell Oil Diala D.
&RQQHFWLRQER[The connection box is a separate cubicle. One connector for the measuring cable going to thecontrol desk is provided.
&RROLQJ
The transformer tank can be fitted with cooling radiators. The insulating oil is conducted throughthis tank by natural convection, and it is thus cooled. Cooling type is ONAN.
3URWHFWLRQDQGVDIHW\IHDWXUHV
In case of a breakdown on the Device Under Test (DUT), the integrated flash detector switches
off the system immediately. The output current and voltage are measured and monitored at thecontrol desk. The transformer is not completely filled with oil. The remaining air volume (aircushion) allows an oil expansion according to the oil temperature. This air cushion is connectedto the outside via a Orange-gel dehydrator. An oil temperature indicator is mounted on each
module.
%DVHThe transformer tank is provided usually with a flat base.

10

'LPHQVLRQVDQGZHLJKWV VRPHH[DPSOHVRQO\

 !"#%$&'  

$+  !)BC$ 9:DC





PK 30-30

30

30

PK 70-70

70

PK 90-150

6, '" , $".-<-=><7?

=, )@$ #$, +!  %$ < 1 $  !+ 9:, )@"&A!  %$ < 1

5)

5)

0.8 x 0.8 x 1.2

170

600

70

1.0 x 1.0 x 1.7

300

1300

90

150

1.5 x 1.3 x 2.5

390

2500

PK 100-600

100

600

1.9 x 1.7 x 2.8

1’600

6’000

PK 150-75

15075

1.1 x 1.4 x 2.9

600

1’600

PK 210-300

210

300

1.8 x 1.6 x 3.9

1’600

4’100

PK 250-50

25050

1.8 x 1.2 x 3.3

800

2’400

PK 600-1’260

600

1’260

9.5 x 2.4 x 4.5

15’00028’000PK 900-900

900

900

12.0 x 2.4 x 6.0

19’00035’000

Other voltages, current or duty cycles are possible upon request !
Dimensions are given with HV bushing installed.

([DPSOHRIDN9¶N9$V\VWHPZLWK6) E EXVFRPSULVLQJGDPSLQJUHVLVWRUFRXSOLQJFDSDFLWRU 6) E DLUEXVKLQJ

11

([DPSOHRIDN9N9$WUDQVIRUPHUZLWKRLO6) E EXVKLQJ([DPSOHRIDN9¶N9$WUDQVIRUPHUZLWKRLODLUEXVKLQJ

12

9ROWDJHGLYLGHUFRXSOLQJFDSDFLWRU+9ILOWHUThe coupling capacitors of the series KK or TK (and 9230) consist of 1 or more modular units,
built into glass fibre reinforced epoxy tubes. Their applications are:
• Partial discharge measurements with an optional coupling quadripole.
• Measuring AC voltages in the industrial frequency range.
• Attenuating interferences coming from the HV side (together with a HV inductance)
7HFKQLFDOGDWDRI..VHULHVL MN O PRQ5I

U P HPRV W O G

STL
100-1

FG HIKJJFG HI

X5Y

Z ['\I^]I N
P^O _ XHU`I W QabO `[W P c I^O I e5O MH
I N IRV^O e M5f5IK[

gPbhIi e P c I
fW c I X h5W M X g

jkI W QabO"&A!  %$ < 1

cdc

cdc

cdc

S^Q

100

1

≤1

B

720

300

350

15

200-1

200

1

≤1

B

1640

350

850

60

300-1

300

1

≤1

B

2600

660

1500

150

400-1

400

1

≤2

B

3300

1580

1500

270

600-1

600

1

≤3

C

4600

1900

2100

490

800-1

800

1

≤5

C

6000

1900

3100

650

D

H

H

D

B

B

Fig. B

Fig. C

6SHFLDO+9ILOWHULQGXFWDQFHFRQILJXUDWLRQ+LJKYROWDJHILOWHUIRU..VHULHV RSWLRQ 
By adding an inductance to the coupling capacitor, they form the high voltage filter KKF, which
attenuates interferences coming from the high voltage reactor / transformer side. Following
inductance is available:FG HIl X fmV^O W ]5W O G
c `nP^op^V m5e e I X O
qjkI W QabO r X I^OS^QU P HPRV W O GM iJJ
X5Y

F 600-2

600

2

3

≤1

Typical insertion loss (50 Ω / 50 Ω) at 40 kHz - 400 kHz

≥

20 dB

13

&RQWUROVW\SH27
'HVFULSWLRQThe Operating Terminal OT 247 provides a safe andeasy computer aided operation of transformer-type
AC high voltage test systems. The unit is built into astandard 19" desktop housing. It has a high electromagnetic compatibility and does not need additional
screening. Due to the built-in safety interlocks theoperator can fully concentrate on the test object.
As an option, the more sophisticated OT 257 can beoffered.
6RIWZDUH&RQWUROVW\SH27

The program allows the following operations:
•
•
•
•
•

Switching On/Off of the primary circuit breaker
Switching On/Off of the contactor (High Voltage On/Off)
Manual variation of the output high voltage, two speed levels
Automatic zero start-up after switching off the high voltage
Automatic setting of the output high voltage to a preset value with a pre-set
speed (kV/s)• Timer for switching off the high voltage after a preset time
At any time and in addition to the output high voltage a selection of four of the following
information can be displayed:••••

Status of the protection system
Status of the safety circuit and the emergency trip
Output voltage and current of the regulating transformer
Timer




+LJK9ROWDJHPHDVXUHPHQWThe measuring signal is derived from the built-in HV divider of the PK type transformer. The valueof the high voltage is permanently displayed, either as peak value/√2 or as RMS value. In case of
flashover at the test object the control unit automatically stores the last voltage measurement.
Measuring error of the electronic± 0.5 % of the measured value between 10 %and 100 % of the system output voltage

Measuring error of the complete measuringsystem (divider/coupling quadripole,electronic system) at 50 / 60 Hz.

± 1 % of the measured value between 10 %and 100 % of the output voltage

14

6SHFLDOVROXWLRQV'DPSLQJUHVLVWRU'HVFULSWLRQThe damping resistor consist of 1 or more modular units, built into glass fibre reinforced epoxy
tubes. Its application is.
• protecting the high voltage AC test transformer from transients when a flash-over occurs.
They are built for indoor use and connected between the test transformer and the voltage divider
electrodes. Their resistance is in the range of 1 kOhm.

7\SLFDOGDPSLQJUHVLVWRUDUUDQJHPHQWRQDN9V\VWHP

2LOH[SDQVLRQGHYLFH
'HVFULSWLRQThe transformer is fitted with an oil expansion device placed above its tank cover. The expansion
device is connected to the tank through a Buchholz or DGPT 2 relay. The expansion device is notcompletely filled with oil. The remaining air volume (air cushion) allows an oil expansion
according to the oil temperature. This air cushion is connected to the outside via an orange-gel
dehydrator. For outdoor service, the air volume is enclosed in a rubber bubble, avoiding therefore
direct contact with the oil. This prevents from oil pollution due to moisture.

([DPSOHRIDQRLOH[SDQVLRQGHYLFH

15

6SHFLDO+9OHDGV'HVFULSWLRQFor special applications, the transformer is fitted with a standard MV connector to which a MV
cable can be connected. This solution is however limited to MV applications. This allows to test
devices having the same standard MV connectors and permits a confinement of the HV inshielded components and suppresses the use of oil-air bushings. Furthermore, this solution
allows to carry out sensitive PD measurements in industrial environments and improves thesafety of the operating personnel !

([DPSOHRIDSKDVHN9WHVWV\VWHPZLWK09FDEOHFRQQHFWRUVDQGOHDGV16

7HFKQLFDOVHUYLFHV'HVFULSWLRQ
Haefely Test AG has a dedicated Technical Services dept. with an experienced team ofengineers doing the internal tests as well as the commissioning on-site and final testing of thetest installations. Our Technical Services dept. does also preventive maintenance, repairs andcalibrations if required. This responsive team allows to minimise eventual down-times andassures the shortest possible reaction time should any question arise.
The full coverage of the warranty is granted only if Haefely Test AG has carried out the Technical
Services. The charges for the delegation of our personnel are based on the terms and conditionsof the Swiss Association of Machinery Manufacturers.
,QVWDOODWLRQBig installations require our experienced team of mechanical erectors for supervising theassembly the test systems.

6\VWHPDQG$FFHSWDQFH7HVWVRQ6LWH
Once the system is erected, we delegate our engineers for doing the systems tests at thecustomers’. The system test shall proof that the system works according to the specification atcustomer’s site and gives a first training to the operating staff.
These tests can also be done with a real test object.
7UDLQLQJRI2SHUDWLQJ3HUVRQQHOThe training is carried out by the Haefely senior engineer immediately after the systems tests.
Detailed explanations about the use of the system, controls and measuring instruments are
given, in addition to the operating manuals.
3UHYHQWLYH0DLQWHQDQFH 6HUYLFHYLVLWV
Haefely Test AG can offer a regular service & maintenance visit on-site for checking the system
condition & proposing necessary works. This is particularly appreciated for production line
equipment.
This visit can also be combined with the system re-calibration.

17

$FFHVVRULHV
0HDVXULQJRI3DUWLDO'LVFKDUJHV
By adding a coupling quadripole (option), the coupling capacitor type KK(F) or TK can be used
for measuring partial discharges. Various coupling quadripoles can be used. Digital or analogue
PD detectors can then be used depending of the customer’s needs. Please consult the Tettex
General Catalogue for more information.

s'LJLWDOSDUWLDOGLVFKDUJHGHWHFWRUW\SH''; 0HDVXULQJRIFDSDFLWDQFHDQGWDQG
The standard capacitors type NK are used in conjunction with C & tan δ bridges for the accurate
measuring of capacitance and tan δ values. Digital or analogue bridges can then be used
depending of the customer’s needs. For more details, see the Tettex General Catalogue.
The SF6 insulated standard capacitor is used
together with a C & tan delta measuring bridge(e.g. Tettex 2877) as a comparison standard forexact measurements of the capacitance andtan delta of H.V. equipment. The SF6 insulated
standard capacitor is designed for indoor
service and is of mobile design.

&DSDFLWDQFHDQGWDQδEULGJHW\SH

18

6WDQGDUGFDSDFLWRUN9

2UGHUWH[W'HVFULSWLRQ&RGH- Complete basic system

PSK ... kV, ... kVA- HV transformer

PK ... kV, ... kVA- Switching and regulating cubicle

STL ... kVA- Compensating reactor

KDL ... kVA- Control unit with set of control and measuringcables, 20 m

OT 247 in desk top housing- Voltage measurementincl. in OT 247- One set of operating instructions and test reports
2SWLRQV- Power line &- HV filters

NLFA ... V, ... A
F ... mH, ... A- Computerised control unit with set of control andmeasuring cables, 20 m

OT 257 with desk and minirack- Low voltage protection device

NSP 400 or NSP 1000

- Standard capacitor

NK ... kV, ... nF- Technical services

DEL- Partial Discharge detectors- C & tan δ measuring bridges

several models available,please see the Tettex
General Catalogue- Other possibilities

please contact usN9N9$WHVWWUDQVIRUPHUDQG+9GLYLGHU

19

/LVWRIOHDIOHWV
Cylinder type resonant test systems up to 1800 kV, 40 A

E 152.51

Tank type resonant test systems up to 400 kV, 10’000 kVA

E 152.60

Instrumentation for Partial Discharge, C and tan δ, accuracy andresistance

Tettex General
Catalogue

Haefely Test AG offers also a complete range of impulse test systems
for both impulse voltage and impulse current applications.

7HVWV\VWHPN9N9$

Haefely Test AG
Lehenmattstrasse 353
CH - 4052 Basel
Switzerland

12.2003
Subject to technical modifications without notice.

20

Tel.
Fax.
e-mail+41 61 373 41 11+41 61 373 49 12
sales@haefely.com
www.haefely.com