ITZ ULTRASTABUSER GUIDE

28October2022/Version 3
N° 99.23.98.002.0

Page 1 of 32

TABLE OF CONTENTSTABLE OF CONTENTS .......................................................................................................................... 2
LIST OF FIGURES .................................................................................................................................. 3
LIST OF TABLES .................................................................................................................................... 3
DOCUMENT INFORMATION.................................................................................................................. 3
INTRODUCTION ..................................................................................................................................... 4
RECEIVING AND UNPACKING .............................................................................................................. 6
GENERAL SPECIFICATIONS FOR RACK ELECTRONICS .................................................................. 7
1
Compliance with regulations............................................................................................................ 8
2
Usage precautions and recommendations ...................................................................................... 9
2.1
Terms and symbols ................................................................................................................. 9
2.2
General use and wear ............................................................................................................. 9
2.3
Grounding considerations ........................................................................................................ 9
2.4
Fuses ....................................................................................................................................... 9
2.5
Precautions for use ................................................................................................................ 10
2.6
Danger ................................................................................................................................... 10
3
Quick start...................................................................................................................................... 11
3.1
System overview ................................................................................................................... 11
3.2
Setting up............................................................................................................................... 12
4
Introduction .................................................................................................................................... 14
4.1
Main features ......................................................................................................................... 14
4.2
Standard transducer heads ................................................................................................... 14
4.3
Custom transducer heads ..................................................................................................... 15
4.4
Voltage output module ........................................................................................................... 15
4.5
Current transfer ratio and programmability ............................................................................ 16
4.6
Front ...................................................................................................................................... 17
4.7
Rear ....................................................................................................................................... 18
4.8
Transducer head ................................................................................................................... 19
5
Installation...................................................................................................................................... 19
5.1
Mounting requirements for the electronics unit ..................................................................... 19
5.2
Mounting requirements for the transducer heads.................................................................. 20
5.3
Grounding the transducer head ............................................................................................. 21
5.4
Installation.............................................................................................................................. 21
6Offset adjustment .......................................................................................................................... 22
6.1
Adjusting the current offset .................................................................................................... 22
7
I/0-ports .......................................................................................................................................... 23
7.1
Analog Out connector ............................................................................................................ 23
7.2
4 mm “Banana” Current Output terminals ............................................................................. 23
7.3
Status/Interlock connector ..................................................................................................... 24
8
Absolute maximum ratings ............................................................................................................ 26
9Packaging ...................................................................................................................................... 26
10
Sweep function during overload status ..................................................................................... 26
11
Thermal protection ..................................................................................................................... 26
12Over current protection - Electrical specifications ..................................................................... 26
13
Transducer head connector ....................................................................................................... 28
14
Operating instructions ................................................................................................................ 28
14.1 Switching on power ............................................................................................................... 28
14.2 Using the ITZ ULTRASTAB in current mode ......................................................................... 28
14.3 Connecting directly to a current measuring device ............................................................... 29
14.4 Connecting to an external burden resistor (current output) ................................................... 30
14.5 Connecting the ITZ ULTRASTAB to a DMM or high impedance amplifier (voltage output) . 30
15
Theory of operation ................................................................................................................... 31
15.1
Basic principle of ITZ ULTRASTAB current transducers ..................................................... 31
16
Maintenance .............................................................................................................................. 32

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LIST OF FIGURES
Figure 1: System overview for Current Output ...................................................................................... 11
Figure 2: System overview for Voltage Output ...................................................................................... 11
Figure 3: Front panel of electronics rack ............................................................................................... 17
Figure 4: Back panel of electronic rack ................................................................................................. 18
Figure 5: Analog out connector pinout .................................................................................................. 23
Figure 6: Wiring schematics to current measuring device .................................................................... 29
Figure 7: Wiring schematics to external burden resistor ....................................................................... 30
Figure 8: Wiring schematics to high impedance load ............................................................................ 30
Figure 9: Block diagram showing the zero flux detector principle ......................................................... 31

LIST OF TABLES
Table 1: General specifications for rack electronics ................................................................................ 7

DOCUMENT INFORMATION
History
05.01.2012 Creation of user manual
06.02.2013 Replaced Manual title by user guide
title (page 1) + replaced LEM Danfisik by LEM
Switzerland + added picture page 11
Modified some pictures
18.01.2022: Added some data according to theexternal laboratory
28.10.2022: Modified picture (page 1); added
maximum power consumption for all ITZ
products + ITZ 6100-S (page 7) + replaced LEM
Switzerland by LEM International (all pages) +changed warranty statement picture (page 3) +added “Packaging” paragraph (page 9) + added
2.6 paragraph (page 10) + modified front panel
picture (page 17) + modified back panel picture(page 18)

28October2022/Version 3
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VersionVersion 0
Version 1
Version 2

Version 3

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INTRODUCTION
Congratulations with your purchase of LEM ITZ Ultrastab.
The ITZ Ultrastab system provides a flexible yet user-friendly platform for use inlaboratory, test facility and industrial applications where the highest performance
fluxgate current sensing is needed. The platform offers full-scale current sensing
from 2000 A and up to 24000 A by utilizing a broad range of compatible current
measuring heads.
Please read this user guide carefully before use. It contains information on how to set
up and use the ITZ Ultrastab and how to build an ultrahigh precision system. In caseof unanswered questions do not hesitate to contact either LEM International S.A. or
our local distributor directly.
IMPORTANT: LEM International S.A. will not be held responsible for useof the ITZ Ultrastab unit under conditions and/or in application setups notsupported by the information in this user guide.

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WARRANTY STATEMENT

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RECEIVING AND UNPACKING
The shipping material and the ITZ ULTRASTAB should be thoroughly inspected forsigns of obvious physical damage immediately upon receipt.
All materials in the package should be checked against the enclosed packing list anddelivery note. LEM International S.A. will not be responsible for any shortages unless
notified no later than 14 days after receiving.
IN CASE OF DAMAGE
If the equipment is damaged in any way, a claim should be filed with the shipping
agent, and a full report of the damage should be forwarded to LEM International S.A.
or our local representative immediately upon receiving.
Upon receipt of this report, LEM International S.A. will forward instructions
concerning the repair, replacement or return shipment.
Please include the Type No., Serial No., and Order No. for the ITZ Ultrastab on any
communication with LEM International S.A. or our local representative.

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GENERAL SPECIFICATIONS FOR RACK ELECTRONICS
Electrical Data – MAINS INPUT
Mains input voltage
100-240 V AC (±10 %)IEC-type inlet socket OVCII and PD2

Mains input frequency
Fuses

Internal fuses, not user-replaceable

50-60 Hz
2.5 At / 240 V AC

Maximum power

76 W

ITZ 2000-S; ITZ 2000-SB;
ITZ 2000-SPR;
ITZ 2000-SBPR;
ITZ 5000-S; ITZ 5000-SB

Maximum power

163 W

ITZ 6100-S

Maximum power

137 W

ITZ 10000-S; ITZ 10000-SB

Maximum power

202 W

ITZ 16000-S; ITZ 16000-SB

Maximum power

300 W

ITZ 24000-S

Electrical data – ANALOG OUTPUT PORT
Full-scale output current±1 A (±2 or ±3 A)
Full-scale output voltage±10 V
Output impedance< 1 Ohm
Electrical data – STATUS/INTERLOCK PORTMax collector-emitter
60 V
voltage, off-state
Max reverse collector5V
emitter voltage, off-state
Max collector-emitter
10 mA
current, on-state
On-state saturation<1V
collector-emitter voltage
Physical data – Electronics rack
Dimensions
480 x 88 x 430 mm
Weight8.4 kg (9.2-10 kg)
Operating conditions
Temperature
Temperature
Maximum primary conductor
temperature
Humidity
Altitude
Environmental conditions
Cooling conditions
Storage conditions
Temperature
HumidityNote:

10 … +40 °C
0 … +55 °C-S and –SB versions-SB versions-SB versions

W x H x D, incl. handles/connectors
Value for 2000-5000 A systems (10kA/16 kA–24 kA systems)
For rack
For head

100 °C
20 … 80 % RH
2000 m 1)
Internal fan-20 … 85 °C
20 … 80 % RH

Non-condensing
IndoorHead and electronic

1) Insulation coordination at 2000 m.

Table 1: General specifications for rack electronics
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1

Compliance with regulations
FCC statement
This equipment complies with the limits for a Class A digital device, pursuant
to part 15 of the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference when the equipment is operated in acommercial environment. This equipment generates, uses, and can radiateradio frequency energy and, if not installed and used in accordance with the
instruction manual, may cause harmful interference in which case the user will
be required to correct the interference at his own expense.
CE statement
This product has been tested and found to comply with the following
standards.
Electrical safety:

IEC 61010-1: 2010 + A1 (2016)

Electromagnetic Compatibility:
Emission:
EN 61326-1: 2013
Immunity:
EN 61326-1: 2013
A technical file is kept available at:
LEM International S.A.
Route du Nant-d’Avril, 152
CH-1217 Meyrin

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2

Usage precautions and recommendations
The following precautions are recommended to insure your safety and toprovide the best operating conditions of this instrument. If this equipment isused in a manner not specified by the manufacturer, the protection provided
by the equipment may be impaired.

2.1

Terms and symbols
These terms and symbols may appear in this manual or on the product.
WARNING: Warning statement identifying condition or practices that
could result in human injury or loss of life.
CAUTION: Caution statement identifying conditions or practices that
could result in damage to the product.
DANGER: High Voltages.

!
!

Protective Ground Conductor Terminal.

2.2

General use and wear!

2.3

CAUTION: Do not place any heavy objects on the instrument.
Avoid severe impacts or rough handling that could damage the instrument.
Use electrostatic discharge precautions while handling and making connections to the
instrument.
Do not place bare or unterminated wires into the connectors of the instrument, only
mating connectors and adapters.
Do not block or obstruct the ventilation openings on the side panels and over the heatsink.

Grounding considerations
To avoid the risk of electrical shock it is mandatory to observe proper
grounding practices.

!

WARNING: To avoid electrical shock the power cord protective grounding
conductor must be connected to earth ground.
All transducer heads must be connected to earth ground as described in section
5.3.

Failure to establish a functional ground connection to earth may lead tohazardous errors and cause malfunction and/or measurement inaccuracies.
2.4

Fuses

!

WARNING: The unit has no user replaceable fuses. In the event that fuses needreplacement please consult your local LEM Sales representative. Please include Typeand Serial no. with all communication with LEM International or the local representative.

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2.5

Precautions for use
Due to the nature of the zero-flux based transducer principle it is necessary totake the following precautions:

!
!
2.6

CAUTION: Do not subject the system to primary current without mains power applied.

CAUTION: Do not operate the system with a disconnected secondary when the system
is subject to primary current.

DangerCaution, risk of electrical shock
Use caution during installation and use of this product; certain parts of the module can carry hazardous
voltages and high currents (e.g., primary conductor).
Ignoring this warning can lead to injury and or/or cause serious damage.
De-energize all circuits and hazardous live parts before installing the product.
All installations, servicing operations and use must be carried out by trained and qualified personnel
practicing applicable safety precautions.

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3

Quick start

3.1

System overview

Figure 1: System overview for Current Output

Figure 2: System overview for Voltage Output
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3.2

Setting up
To quickly get your new ITZ ULTRASTAB system operational, follow the
instructions given below.
1. Connect the transducer head to the unit using the supplied transducer head
cable and mount the programming plug in the connector on the transducer
head if your system has the programming feature – please note that not alltransducer heads are programmable.
2. Connect a Digital Multimeter (DMM) to the unit.
If your unit has current output (-S or –SPR versions):
The primary access is through the Analog Output Port, using the Current
Output Adaptor supplied with the ITZ system.
The unit also has a secondary output through the 4 mm banana terminals on
the back panel of the ITZ unit. Since the primary and secondary current
outputs are connected electrically in series internal to the electronics the 4
mm banana terminals should be left shorted (using the supplied shortingplug) for this exercise.

!

CAUTION: It is MANDATORY that the secondary current path remains CLOSED
whenever the system is powered – if not, there is a risk of permanently damaging thesystem. Furthermore, if there is no closed secondary current path the system will not beable to produce measurable output. The secondary current path is closed either by
shorting the 4mm banana terminals or by connecting a series (measuring) resistor atthese outputs.

Using standard 4 mm banana test leads, connect the red wire on the Current
Output Adaptor to the current input terminal on the DMM and the black wire of
the adaptor to the common terminal on the DMM. Set the DMM to measure
DC current in a range greater than:••••±1 A for ITZ 2000-SPR (-SBPR)±2 A for ITZ 2000-S (-SB), ITZ 5000-S (-SB), ITZ 10000-S (-SB) and
ITZ 16000-S (-SB)±2.44 A for ITZ 6100-S±3 A for ITZ 24000-S.

IMPORTANT:

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Refer to page 23 for EMC precautions for the 4 mm banana
terminal port.

Page 12 of 32

If your unit has a voltage output (-SB or –SBPR versions):
Connect the Analog Output Cable to the Analog Output Port. Using standard
4 mm banana test leads, connect the red wire of the cable to the positive
terminal on the DMM and the black wire to the common terminal. Set the
DMM to measure DC/AC voltage in a range greater then ± 10 V.
The blue wire of the cable is connected to the cable shield and to chassis
ground.
Make sure the supplied shorting plug is installed on the 4 mm banana
terminals as described in the previous section.

!

CAUTION: It is MANDATORY that the secondary current path remains CLOSED whenever thesystem is powered – if not, there is a risk of permanently damaging the system. Furthermore, if
there is no closed secondary current path the system will not be able to produce measurable
output. For voltage output versions this is ensured either by shorting the 4 mm banana
terminals using the supplied shorting plug, by connecting a DMM in low-impedance current
measuring mode or by connecting a measuring resistor to the 4 mm banana terminals.

3. Connect the mains cord.

!

CAUTION: Since the ITZ system has no mains switch the unit will be powered immediately byinserting the mains cord.

240 V AC main
110 V AC main

Power Cable,
C13, IEC to CEE 7/4,
Schuko, 16 A, 250 V
Power Cable,
C13, IEC to NEMA 5-15,
10 A, 125 V

4. The ITZ ULTRASTAB will now measure the current running through thetransducer head. On the front plate the status of the unit can be monitored
using the status LED panel.

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4Introduction

4.1

Main features
The ITZ ULTRASTAB is a high precision current measuring device based on
the Flux-gate principle. It can measure current in both the DC and AC domain.
The instrument can be configured in a variety of ways to suit the user’s
demands. Amongst the ITZ ULTRASTAB main features are:• Current or voltage output• Input range from 0 to ±24000 A• Status signals for interfacing with other equipment
The current measuring range is configurable depending on the transducer
head.

4.2

Standard transducer heads
ITZ ULTRASTAB can be delivered with the following transducer heads.
1. ITZ 2000-50-PR – programmable in steps of 125 A from 125 A to2000 A. Turns ratio (default) of 2000 :1;
Nominal secondary current of 1 A; Aperture Ø 50 mm
2. ITZ 2000-50 – non-programmable, wide-bandwidth;
Turns ratio of 1000 :1; Nominal secondary current of 2 A;
Aperture Ø 50 mm
3. ITZ 5000-140 – non-programmable. Turns ratio of 2500 :1
Nominal secondary current of 2 A; Aperture Ø 140 mm
4. ITZ 6100-140 – non-programmable. Turns ratio of 2500 :1
Nominal secondary current of 2.44 A; Aperture Ø 140 mm
5. ITZ 10000-100 – non-programmable. Turns ratio of 5000 :1;
Nominal secondary current of 2 A; Aperture Ø 100 mm
6. ITZ 16000-150 – non-programmable. Turns ratio of 8000 :1;
Nominal secondary of 2 A; Aperture Ø 150 mm
7. ITZ 24000-150 – non-programmable. Turns ratio of 8000 :1;
Nominal secondary of 3 A; Aperture Ø 150 mm

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Please note that systems are always downwards compatible in thesense that a smaller transducer head can be used with the rackelectronics from a larger system. i.e., if you have purchased an ITZ10000-S system you will be able to use a 2000 A transducer head withyour rack electronics without any limitations. The system will adapt itself
to this.
However, the system is not generally upwards compatible. i.e., you will
not generally be able to use a larger head with the rack electronics froma smaller system. If you want to expand the measuring range of yoursystem by using a larger transducer head, please consult your local LEM
SA Sales representative to obtain information on existing options and
cost.
4.3

Custom transducer heads
For current measurement of 10 kA and beyond certain customizing may berequired. Your local LEM SA Sales representative will be able to assist you
with custom requirements for turns ratio, programmability options etc.

4.4

Voltage output module
In addition to the different transducer heads a system can also be equippedwith a VOM (Voltage Output Module). This module will convert the output
current to an output voltage of ±10 V (nominal full-scale).
Three types VOMs are available, one for each nominal output current range(1, 2 or 3 A). In all cases, the output current is also available for monitoring
either by the 4 mm banana jacks on the back panel or with the Analog Output
Cable.
If you have ordered your system with the “B” option (e.g. ITZ 5000-SB), it
already has a VOM installed. If your system was ordered as a standard
current output system, you can have a VOM retrofitted. Please contact yourlocal LEM SA Sales representative to obtain information on existing options
and cost.

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4.5

Current transfer ratio and programmability
The system can generally be considered as a “current transformer also
working at DC”. The primary winding is the wire through the center hole of thehead, and the secondary winding is the compensation winding of thetransducer head. The ratio between these two windings defines the current
transfer ratio ( N ) of the system.
The smaller transducer heads come with a programming option.
As the nominal output current ( IS N ) is fixed (defined by the transducer head)
and the maximum input current ( IP ) can be changed using a programming
plug, the current transfer ratio can be changed enabling the user to program
the system to many different maximum input currents.
Example:A system with an ITZ 2000-50 PR transducer head programmed to 1500 A willproduce 1 A when the primary current is 1500 A.
The current transfer ratio of the system is then:=N

IP
1500 A== 1500IS N
1AWhen a system is equipped with a VOM, the output current will be converted
to a voltage. The maximum nominal output voltage ( U out ) is fixed at 10 V.
Thus the ratio ( S ) from the example above can be found as:=
S

IP
1500 A== 150 A V
U out
10 V

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4.6

Front
1

2

Figure 3: Front panel of electronics rack

On the front of the ITZ ULTRASTAB there is an LED indicator panel:
1

POWER:
This LED is lit (Blue) when the unit is on.
ACTIVE:
This LED is lit (Yellow) when the transducer output is active, with IP higher
than approximately 1 % of nominal full-scale output.
HIGH IP:This LED is lit (Yellow) when the transducer output is active with an IP higher
than 105 % of nominal full-scale output.
OVERLOAD:
This LED is lit (red) when the transducer head saturates due to excessive
primary current.
2000 A to 24000 A:
These LEDs are lit (Yellow) when a transducer head with the corresponding
full-scale range is connected to the ITZ ULTRASTAB.
CUSTOM:
This LED is lit (Yellow) when the system setup has detected a custom head
configuration.
STATUS:This LED is lit (Green) when the status of the unit is OK.

2

Output current offset adjustment
An offset adjustment is positioned next to the left-most handle. The
adjustment is accessible using a miniature slotted screwdriver.

!

CAUTION: Please refer to section 6 for instructions on how to adjust offset correctly.

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4.7

Rear

Figure 4: Back panel of electronic rack

All connections on the ITZ ULTRASTAB are located on the rear of the unit.
1.

IEC power inlet: This connector accepts a standard IEC power cord.
IMPORTANT: The power inlet also serves as mains switch.
IMPORTANT: The unit operates with a universal mains input. Thismeans that the unit does not require any switching between mains
voltages as long as the supplied mains voltage is within 100-240 V AC
(50-60 Hz).

2.

3.

IMPORTANT: The unit has no externally accessible user-serviceablefuses. If the unit requires replacement of fuses please contact yourlocal LEM International S.A. sales representative.
Type / Serial number plate. Three individual S/Ns may be listed here:
One for the ITZ electronics, one for the matching head and one(optional) for the installed VOM.
Transducer head: Connection to the transducer head.
CAUTION: The secondary current path must
be closed with the system powered. This
includes both the current output in the
Analog Out connector and the 4 mmbanana terminals – if one of them is used,
the other must be shorted with the supplied“Short-plug”.

!

4.
5.
6.
7.
8.

Analog out: Output connection to a DMM or other equipment.
Current +/-: Secondary current output.
Monitor: Voltage output with a low-precision voltage output derived
from the secondary current. Output is ±1 V full-scale.
Status/Interlock signal outputs.
Option A+B: These positions are for future expansion or customization.

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Ventilation exit

The main heat sink has an airflow exit centred on the back panel. Inlet holes are on the sidepanel of the chassis.

! CAUTION: Do not block the airflow to/from the unit.
4.8

Transducer head
The transducer head is connected to the electronics rack using a dedicatedcable with a multi-pin bayonet-style connector. Various cable lengths areavailable.
If the transducer head is programmable, it also has a D-sub 25-pin maleconnector. This connector is used with suitable programming plugs(accessory) – for further information, please refer to section 4.5 for further
information on programmability.

!

CAUTION: A programming plug must be connected to theprogramming port of a programmable head when the system is
powered.

5

Installation

5.1

Mounting requirements for the electronics unit
The ITZ ULTRASTAB can be mounted in either a rack-based system or as astand-alone unit using the supplied rubber feet.

!

CAUTION: The unit must be mounted horizontally. To ensure
proper cooling, keep ventilated ides on side and back panel free.
Failure to do this may result in improper cooling of the system
which may lead to malfunction of the unit.

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5.2

Mounting requirements for the transducer heads
ITZ 2000-50 (-PR): The 2000 A transducer head must be installed using two
M8 screws. The head may be mounted in any orientation. Please observe thatthe length of the screws may not exceed the length D shown in figure 5. To
calculate the maximum length of the mounting screw, measure the thicknessof the mounting substrate C and add the length A + B which is 10 mm+ 15 mm.
Max. Screw length:
D = 10 + 15 + C [mm]Transducer core

D

A

10

B

15

C

Mounting plate
Mounting substrate
Mounting screw

Figure 5

CAUTION: Using too long screws may cause damage to the inner parts of thetransducer head and lead to malfunction.

ITZ 5000-140, ITZ 6100-140, ITZ 10000-100:
These transducer heads are mounted using four M10 screws inserted into theholes on the brackets.
These heads may be installed in any orientation.
ITZ 16000-150, and ITZ 24000-150:
These transducer heads are mounted using two M12 screws inserted into theholes under the head.
This head must be installed in vertical position.

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5.3

Grounding the transducer head
For safety reasons all types of transducer heads must be properly grounded.
Follow the description below for the appropriate transducer head in order toestablish a good grounding connection.
ITZ 2000-50 (-PR): A ground wire (min 1.5 mm2) with an Ø 8.3 mm ring
tongue must be connected to the transducer head.
The ring tongue is placed on one of the 4 mounting screws before mounting
the head.
ITZ 5000-140, ITZ 6100-140, ITZ 10000-100: A Ground wire (min 1.5 mm2)with an Ø 10.3 mm ring tongue must be mounted to the transducer head.
The ring tongue is placed on one of the 4 mounting screws before mounting
the head.
ITZ 16000-150 and ITZ 24000-150: A Ground wire (min 1.5 mm2) with anØ 12.3 mm ring tongue must be mounted to the transducer head. The ring
tongue is placed on one mounting screw before mounting the head.

5.4

Installation
1. Establish the ground connection (see section 5.3).
2. Mount the provided connection cable between the ITZ ULTRASTAB
electronics and transducer head.
3. Connect the Analog Output Cable as described in section 8.3-8.6.
4. Check that all cables terminated in a plug are correctly installed and thatthe lock screws are tightened firmly.
5. Connect the supplied power cord to the IEC inlet on the unit to turn it on.
The transducer head and electronics can be installed with a transducer head
connecting cable of 30 meters maximum.

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6Offset adjustment
The ITZ ULTRASTAB should occasionally have a current offset adjustment
made to ensure the highest accuracy.
All ITZ ULTRASTAB are offset adjusted with the accompanying transducer
head prior to shipment from the factory. In case the ITZ ULTRASTAB system
has been recalibrated or serviced, and as a minimum after half a year ofoperation, it is advisable to perform an offset adjustment with the selectedtransducer head connected prior to any measurement in order to achieve thehighest accuracy.

6.1

Adjusting the current offset
To adjust the ITZ ULTRASTAB please follow these steps.
1. Connect a DMM capable of measuring micro amps (µA) to the Analog
output port using the current output adaptor cable.
2. Connect the mains cord to the IEC inlet.
3. Wait for approx. 15 minutes after powering up the system for the unit tostabilize thermally.
4. Locate the offset trim hole on the front of the electronics unit (lower left
corner).
5. Use a trim screwdriver to adjust the offset until the current is as close tozero as possible.

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7

I/0-ports

7.1

Analog Out connector
Normally an appropriate output cable should be used, depending on whether
your system has current or voltage output. It is also possible to configure yourown output cable, bearing the following description in mind.
The Analog out connector (Dsub15-F) contains the following signals:
1. Current return
2. Current return
3. Current return
4. Uo High Sense
5. Uo High Out
6. Ground
7. Uo Low Sense
8. Uo Low Out
9. Current out
10. Current out
11. Current out
12. Uo High Sense
13. Uo High Out
14. Uo Low Sense
15. Uo Low Out

1

8

9

15

Figure 5: Analog out
connector pinout

When using the ITZ ULTRASTAB in current out mode (no VOM installed) only
pin 1, 2, 3 and 9, 10, 11 should be used.
••

Pin 9, 10, 11: Is the current output from the ITZ ULTRASTAB.
Pin 1, 2, 3: Current return path.

When using the ITZ ULTRASTAB in voltage out mode (VOM installed) pin 1–
9, pin 2–10 and pin 3-11 must be shorted. This will loop the current output tothe VOM. The voltage output is then present at pin 4 - 8 and 12 - 15.
IMPORTANT: The sense pins (Uo High Sense on pin 4 and 12, and Uo Low
Sense on pin 8 and 14) must be connected to Uo High Out and Uo Low Out
respectively.

7.2

4 mm “Banana” Current Output terminals
Two standard 4 mm banana jacks are available for easy connection to a low
impedance current measuring DMM.

!

CAUTION: These terminals should be shorted when not in use by use of the
supplied shorter plug.
IMPORTANT: The ITZ system is tested for EMI conformance against industrial
standards. Use of the unshielded 4mm banana current output port can be
critical under circumstances with a high level of external disturbance.

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7.3

Status/Interlock connector

All signals on the Status/Interlock port are optically isolated, Photo couplers type,floating Collector and Emitter.
Four signals are present on the port, each having two dedicated floating pins in the
SUBD9 Male connector:. Collector (C)and. Emitter (E)C

SUBD9 Pin

1

C

C

SUBD9 Pin

6

SUBD9 Pin

2

E

C

SUBD9 Pin

7

SUBD9 Pin

8

SUBD9 Pin

4
STATUSHigh Ip
E

3
ACTIVEOVERLOADE

SUBD9 PinE

SUBD9 Pin

SUBD9 Pin

9

Not Connected

5

Depending on how each signal is wired, It can be “Active Low” or “Active High” asshown below:

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In the Diagram A Active Low Output, the output signal Uout switches to GND when
the corresponding Led is ON.
In the Diagram B Active High Output, the output signal Uout switches to +U when thecorresponding Led is ON.
When the output signal Uout is switched to GND, its value is lower than 0.2V.
When the output signal Uout is switched to +U, its value is equal to +U
outputsignalOVERLOADHigh IP

Diagram

Uout

DescriptionA< 0.2 V

B

+U
+U

A

< 0.2 V< 0.2 V

The transducer head is saturated due to excessive primary
current
The transducer head is not saturated
The transducer head is saturated due to excessive primary
current
The transducer head is not saturated
The primary current is higher than 105 % of nominal full-scale
output
The primary current is lower than 105 % of nominal full-scale
output
The primary current is higher than 105 % of nominal full-scale
output
The primary current is lower than 105 % of nominal full-scale
output
The primary current is higher than approximately 1 %of nominal full-scale output
The primary current is lower than approximately 1 %of nominal full-scale output
The primary current is higher than approximately 1 %of nominal full-scale output
The primary current is lower than approximately 1 %of nominal full-scale output
When the unit status is OK (Normal operation)
When the unit status is not OK (Supply fault, overtemperature conditions, Current overloads or Transducer
head not detected)
When the unit status is OK (Normal operation)
When the unit status is not OK (Supply fault, overtemperature conditions, Current overloads or Transducer
head not detected)

+U
B

+U
< 0.2 VACTIVEA< 0.2 V
+U
+U

B

< 0.2 VSTATUSA< 0.2 V+U

B

+U
< 0.2 VThe power supply voltage +U must be between 4 V and 60 V DC and the resistor
value must be chosen between a minimum value Rmin and a maximum value Rmax
calculated by using the following equations:
Rmin (KΩ) =

+𝑈𝑈
3.4

and Rmax (KΩ) =

+𝑈𝑈
1.7

Some recommended standard values are given in the following table:
Power supply Voltage +U
5 V ±5%
12 V ±5%24 V ±5%28October2022/Version 3
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Rmin (KΩ)
1.5
3.5
7

Rmax (KΩ)
3
7
14

R Standard Values
1.8 KΩ ±5 % or 2.2 KΩ ±5 %4.7 KΩ ±5 % or 6.8 KΩ ±5 %10 KΩ ±5 % or 12 KΩ ±5 %Page 25 of 32

8Absolute maximum ratings
Symbol+U
UC E off max
UC E off max
IC E on max

Description
Power supply Voltage
Maximum Off-state Collector-Emitter Voltage
Maximum reverse Off-state Collector-Emitter Voltage
Maximum ON-state Collector-Emitter Current

Specification
60
60
5
10

Unit
V
V
V
mA

Stresses beyond those listed under absolute maximum ratings may cause
permanent damage to the status/interlock signal outputs.

9

PackagingSee datasheets of the products.

10

Sweep function during overload status

The Overload occurs when the primary current IP exceeds a threshold value outside
the measuring range and, consequently, the fluxgate detector becomes completely
saturated.
This threshold value is beyond 110 % of IP N and the precise threshold value isrelated to the transducer head and to the measuring resistor.
When this happens, the ITZ rack electronics will automatically begin to sweep inorder to lock on to the primary current again and the measuring can resume when
the primary current returns in the nominal range between - IP N and + IP N.
In sweep mode, the output current signal will be a slope between ±1 A, ±2 A or
±3 A depending on the transducer head.

11

Thermal protection

12

Over current protection - Electrical specifications

The ITZ series has thermal shutdown circuitry that protects the electronics fromdamage.
The thermal protection circuitry disables the measuring circuit when the rackelectronics temperature reaches approximately 65 °C and allows the transducer tocool.
When the rack electronics temperature cools to approximately 60 °C, the measuring
circuit is automatically re-enabled.

The Over current occurs when the primary current exceeds 120 % of IP N DC.
To detect the over current with primary AC, the secondary current is full-wave
rectified and is time-averaged by a low-pass filter (Note 1).
Depending on the frequency range of the primary current, two cases appear:- Low frequency range: DC – 1.6 Hz (Over current slow)
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In this case, the Over current trip level is set to 120 % of IP N DC.
The secondary current is tracked until the primary AC peak exceeds this trip level.
Then, the rack electronics shut down the measuring circuit and wait until the primary
AC peak becomes lower than the set trip level.
- High frequency range: 1.6 Hz – 1.6 KHz (Over current fast)
In this case, the Over current trip level is set to 160 % of IP N DC.
The secondary current is tracked until the primary AC peak exceeds this trip level.
Then, the rack electronics shut down the measuring circuit and wait until the primary
AC peak becomes lower than the set trip level.
The DC – 1.6 KHz characteristics with a sine-wave primary AC is shown in thefollowing table:
Primary current frequency (Hz)DC (0Hz)
0.2
0.5
1
1.5
2
5
50
800
1600

Typical value of primary peak current to detect overcurrent state
120 % of IP N DC
122 % of IP N DC
126 % of IP N DC
130 % of IP N DC
140 % of IP N DC
147 % of IP N DC
157 % of IP N DC
160 % of IP N DC
170 % of IP N DC
186 % of IP N DC

Under these conditions:- The signal Status (Contact between Pin 4:C and Pin 9:E) switches off, this signal
becomes open (No current from collector to emitter) to indicate that the unit is not
OK.
- The green Led located on the front panel switches off (fault state)- The transducer is protected against damage that the Over current primary AC may
cause to the electronics.
The transducer will automatically start again to work when the primary AC peak
becomes lower than the threshold value indicated in the table above.
Note 1:This full-wave rectification creates a ripple voltage with an average DC component
and an AC component whose frequency is twice the primary current frequency .The
magnitude of the ripple voltage varies with the primary current frequency. Thismagnitude will be decreased if the frequency is increased.

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13Transducer head connector
The circular multi-pin bayonet-style connector is used to connect thetransducer head to the electronics.
It is critical to ensure the signal integrity in this I/O interface in order tomaintain the very high performance level this system can achieve. As aconsequence, pins in this I/O interface are not available for the user.

14

Operating instructions

14.1 Switching on power!

CAUTION: Before switching on the power make sure that there is no current
running through the transducer head.
IMPORTANT: The ITZ rack electronics has no MAINS switch. To power off theunit disconnect the mains plug at the power inlet.

Before powering up the ITZ ULTRASTAB be sure to check the following:
1. Check that all cables terminated in a plug are correctly installed and thatthe lock screws are tightened firmly
2. Check that the system is properly grounded through the mains connection
and that the transducer head is grounded according to the directions given
in section 5.3.
3. Connect the power cord to the mains inlet
4. The ITZ ULTRASTAB will now run through its power up sequence. After a
few second the unit is ready and the status of the unit can be seen on thefront panel LEDs
5. Switch primary current on. The ACTIVE LED will turn on.
14.2 Using the ITZ ULTRASTAB in current mode
When using the ITZ ULTRASTAB without a VOM installed there are
essentially two ways to measure the output. It can either be connected to a
current measuring device or to an external burden resistor.

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14.3 Connecting directly to a current measuring device
Connecting the ITZ ULTRASTAB directly to a current measuring device like a
DMM or a power analyser, can easily be done from the current output portwith two standard 4 mm banana plugs. Take care that both terminals arefloating relative to ground. The red wire carries the output current while theblack is the current return path. Simply connect these two wires to yourcurrent measuring device using standard laboratory test leads with 4 mmbanana terminals.

Figure 6: Wiring schematics to current measuring device

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14.4 Connecting to an external burden resistor (current output)
If an external burden resistor is to be connected to the ITZ ULTRASTAB theconnection shown below should be used.

Figure 7: Wiring schematics to external burden resistor

In addition to the standard current output cable of 1.5 m length a 5 m longcurrent output cable is also available. Both cables use two twisted pairs inorder to reduce the resistance and are terminated in three 4 mm female
banana sockets for easy connection to other equipment.
14.5

Connecting the ITZ ULTRASTAB to a DMM or high impedance amplifier(voltage output)
When connecting the ITZ ULTRASTAB to a DMM or high impedance load involtage mode (VOM installed) use the connection shown below. This diagram
is equal to the standard voltage output cable. This cable uses a single twisted
pair and is terminated in three female banana sockets for easy connection toother equipment.

Figure 8: Wiring schematics to high impedance load

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15

Theory of operation

15.1

Basic principle of ITZ ULTRASTAB current transducers
The ITZ ULTRASTAB current transducers are delivered in a series covering
galvanic insulated measurements of currents from DC to 500 kHz ranging
from 40 A to 24 kA.
These precision current transducers use a zero flux detector principle
controlling a compensation current which counterbalances the ampere-turns
generated by the primary current. Due to a balanced zero flux detector
principle the output noise level is extremely low by nature and a resolution on
the order of 2 x 10-8 is achieved.
Below is shown a block diagram of the zero-flux detector principle.

TFigure 9: Block diagram showing the zero flux detector principle
The transducer head core (1) is the basic body structure. The cores (2) and(3) are the flux detectors coupled to the zero-flux detector circuitry by meansof the coils L1 and L2.
Coils L1 and L2 are coupled in parallel or series depending on the model, with
opposite phase to reduce any unwanted flux generated in core 1.

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With primary current (IP) flowing through primary winding L4, a magnetic flux will
be generated in the body structure and detected by the detector cores. An error
signal will be generated, controlling the amplifier A1 to drive a current through thecompensation, winding L3. When counterbalance is obtained, i.e. zero flux is reestablished, the compensation current, multiplied by the number of turns inwinding L3, is a true representation of the instantaneous primary current (IP).
The zero flux detector circuitry operates from true DC to about 1 Hz. For
higher frequencies the “AC pick up” winding L5 performs as a feedback error
signal via the amplifier A3 which widens the active bandwidth of thetransducer to more than 10 kHz.
Above 10 KHz the Define CCT the transducer operates as a passive current
transformer with its -3 dB limit varying from 300 KHz to 1 MHz depending on
the size and construction of the head.

16

Maintenance
The ITZ ULTRASTAB with current output does not require any maintenanceunder normal operation except for the offset adjustment explained in section
6.
The ITZ ULTRASTAB with voltage output requires offset adjustment as
described in section 6.
The system is a calibrated entity that should be recalibrated every 2 years toensure the calibration level of the system. To get your ITZ ULTRASTAB
recalibrated we recommend shipping it to LEM International S.A.
If the unit needs service, please contact LEM International S.A. our local sales
representative.

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