Voltech AT3600 User manual

VOLTECH INSTRUMENTS
AC Interface Fixture
User Manual

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE - 2 -
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Voltech Part Number: 98-072, Issue 7

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE - 3 -
DANGER OF ELECTRIC SHOCK
Only qualified personnel should install this equipment, after reading and understanding this user manual. If in doubt,
consult your supplier.
Please consult the safety information section of this user manual before installation and use.
RISQUE D'ELECTROCUTION
L'installation de cet équipement ne doit être confiée qu'à un personnel qualifié ayant lu et compris le présent
manuel d'utilisation. Dans le doute, s'adresser au fournisseur.
GEFAHR VON ELEKTRISCHEM SCHOCK
Nur entsprechend ausgebildetes Personal ist berechtigt, diese Ausrüstung nach dem Lesen und Verständnis dieses
Anwendungshandbuches zu installieren. Falls Sie Zweifel haben sollten, wenden Sie sich bitte an Ihren Lieferanten.
RISCHIO DI SCARICHE ELETTRICHE
Solo personale qualificato può installare questo strumento, dopo la lettura e la comprensione di questo manuale.
Se esistono dubbi consultate il vostro rivenditore.

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE - 4 -
Contents
1. Introduction...........................................................................6
1.1. Features & Abilities.............................................................................................................................................6
1.2. Package Contents ..............................................................................................................................................7
1.3. Choosing an AC Source .....................................................................................................................................8
1.4. Choosing step-up or step-down Transformer...................................................................................................12
1.5. Summary of Advantages & Disadvantages......................................................................................................16
1.6. Operating Description.......................................................................................................................................17
2. Installation...........................................................................18
2.1. General .............................................................................................................................................................18
2.2. Power Amplifier or Source with On / Off Control ..............................................................................................19
2.3. AT Output Transformer.....................................................................................................................................20
2.4. Connectiosn to the Test Fixture........................................................................................................................21
3. Using the AT Editor Software ............................................23
3.1. Configuration of External Source in AT Ediotr..................................................................................................23
3.2. Current Sense Method .....................................................................................................................................28
3.3. Selection of External AC Source in PC Editor..................................................................................................29
3.4. Testing The Complete system..........................................................................................................................30
3.5. Use of X Tests in an At Editor ATP program....................................................................................................33
3.6. Integration of AC Interface tests with IR, HPDC, HPAC, DCRT, ACRT, DCVB, ACVB Tests........................34
3.7. Integration of AC Interface tests with ILK, SURG, MAGI, STRW, WATT, VOC Tests....................................35
4. Technical Information ........................................................36
4.1. Recommended Spares & Accessories.............................................................................................................36
4.2. Details of Connector Functions ........................................................................................................................37
4.3. Using a Current Transformer............................................................................................................................42
4.4. Choosing an AT Output Transformer ...............................................................................................................44
5. Specification .......................................................................45
5.1. Tests Available for Use with the AC Interface ..................................................................................................45
5.2. MAGX – Magnetising Current...........................................................................................................................46
5.3. VOCX – Open Circuit Voltage ..........................................................................................................................47
5.4. STRX & WATX – Stress Wattage & Wattage...................................................................................................48
5.5. Typical External AC Source Specification ........................................................................................................49
5.6. General .............................................................................................................................................................49
5.7. EMC Compliance..............................................................................................................................................50
5.8. EMC Precautions..............................................................................................................................................51
6. Warranty & Service.............................................................52
6.1. Warranty ...........................................................................................................................................................52
6.2. Service..............................................................................................................................................................52
6.3. Obtaining Service and Applications Support ....................................................................................................52
7. Safety Information ..............................................................53
7.1. Safety Features ................................................................................................................................................53
7.2. Safety Instructions ............................................................................................................................................53
7.3. Error Messages ................................................................................................................................................54

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE - 5 -
7.4. Compliance with EN954 ...................................................................................................................................56

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 6
1. INTRODUCTION
Thank you for choosing to use this Voltech product.
If you experience any difficulty during installation or use of the Voltech AC Interface or are unsure of any of its
features or abilities, please do not hesitate to contact either your local Voltech supplier or one of our Voltech
main service centres.
1.1. FEATURES &ABILITIES
The Voltech AC Interface is a versatile, easy-to-use accessory for the Voltech AT3600/AT5600 transformer
tester. The AC Interface:
•Extends the range of wound components that may be tested by the AT3600/AT5600 by allowing a variety
of third-party AC sources to provide the test signal
•Can be used with either
A simple step-up or step-down transformer for 0-600V , < 25W
External sources that provide up to 600V @ 10A, 20Hz to 5 kHz for testing higher power transformers.
•Automatically controls the AC source to optimise test speed and enhance operator safety.
•Integrates the AC source seamlessly into the AT3600/AT5600 environment and allows all other standard
tests to be executed in the same program that is used by the external source.
•Fits into the rear part of the fixture bay on an AT3600/AT5600.
•Provides a convenient method of connection between the source, the AT3600/AT5600 and the test piece.
•Comes with all necessary inter-connecting leads supplied.
•Isolates the AT3600/AT5600 from the external source, when the external source is not being used,
preventing damage to the source during later high-voltage testing.
•Allows a step-up or step-down transformer to be used to boost the voltage or current of the
AT3600/AT5600's internal generator.
•Makes four tests available for use with the AT3600/AT5600 and an AC source:
oMAGX - Magnetising Current (External Source)
oVOCX - Open Circuit Voltage (External Source)
oWATX - Wattage (External Source)
oSTRW - Stress Wattage (External Source)

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 7
1.2. PACKAGE CONTENTS
The following items are supplied with your AC interface. Please check that you have every item and report any
missing items to your Voltech supplier as soon as possible.
Voltech AC Interface Fixture
Kelvin clip leads, 10A rated (Voltech# 78-060)
For use during program design, or when the transformer does not have existing fixturing.
One black (Voltech# 78-067) and one red (Voltech# 78-068) 4mm safety to 4mm stackable AC test leads
For connecting the 'External Source Output' connectors of the Interface to the test fixture.
Two pairs of red (Voltech# 78-057) and black (Voltech# 78-058) 4mm safety to bare tinned leads.
One pair for connecting the external source or transformer secondary to the ‘Input from External Source’
connector of the AC Interface.
The other pair for connecting the 'AT Transformer Drive Output' to the primary of a transformer (if used).
One yellow 4mm and one blue 4mm safety socket.
For fitting to your existing test fixture to accept the leads from the 'External Source Output' of the AC Interface.
One current transformer CT 10-20 (Voltech# 31-132)
A precision current transformer that fits directly onto the AC Interface.
This is rated to 10 Amps AC RMS , with a ratio of 1:20 to step down the current so the AT can measure. This
is the default ratio that is set when you configure the external source in the At Editor program.
Certificate of Conformance

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 8
1.3. CHOOSING AN AC SOURCE
To provide system reliability, integration with existing tests and operator safety, the Voltech AC Interface must
be able to control the output of the external AC source that is being used with it.
The AC Interface allows two distinct types of AC sources to be used for testing:
•A power amplifier or an AC source configured as an Amplifier (analogue control)
•A voltage or current step-up transformer
A power amplifier is an AC source that can be configured so that its AC voltage output is a fixed multiple of a
small AC voltage control input.
The output frequency of a power amplifier is the same as the input frequency of the small AC voltage control.
A power amplifier is Voltech’s preferred choice of an external AC source to be used with the AT3600/AT5600
transformer tester and the AC Interface. Using a power amplifier, the AT3600/AT5600 will:
•Control the ramp-up and ramp-down of voltage to reduce settling time and optimise test speed.
•Control the ramp-up of voltage to reduce inrush current.
•Program any combination of voltage and frequency that the AC source can provide quickly and
accurately. Different voltage / frequency combinations can be used within one program.
•Accurately trim to the desired output voltage to reduce errors due to the regulation of the source
and the resistance of leads and connections.
Voltech recommends the following AC Sources.
1. Chroma Model 61600 Series - A low-cost AC Power Source solution.
•Voltage range: 0-150V/0-300V/Auto
•Frequency: 15Hz – 1000Hz
•Output power from 500VA to 4000VA, depends on model selected.
•For more details, please visit http://www.chromausa.com/product/low-power-programmable-ac-
source-61600/
2. Pacific Power ASX-115T Series - A commonly available single-phase powered AC source that can provide
132V / 106 at 1500VA.
•Frequency: 15Hz - 1200Hz Direct, 45Hz – 1200Hz with output transformer
•It also has a built-in transformer mode, which allows up to 330V.
•For more details, please visit http://www.pacificpower.com/English/Products/ASX-Series.aspx
3. Trek Model 2100HF – A high-frequency, high speed wide bandwidth amplifier.
•Voltage range: 0 – 150Vpk, Output Current: 0 – 300mApk
•Frequency: 0 – 2.6MHz, Slew Rate: 2kV/us typical
•For more details, please visit http://www.trekinc.com/products/2100HF.asp
Power Amplifier
(x 50)
AC Power Out
0 - 250V @ 10A
AC Control In
0 - 7.07 Vrms
(+/-10Vpk)

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 9
1.3.1 Worked Example of Chroma 61602
(CT10-20 module not shown fitted, but will be required)

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1.3.2 AC Source and STEP-UP UP Transformer combined
Note: When using an Amplifier AND an additional external step-up transformer connected to the output of an
Amplifier to increase the output voltage, a non-polarised capacitor must be wired in series with the output of
the Amplifier and the drive of the step-up transformer due to offsets in the Amplifier which cannot be trimmed.
Selecting a capacitor:
C = (Im * N2 ) /( 2 * π* Fm * Vm * 10%)
CVoltageRating = ( 2 * Vm * 10%) / N
Where:
C is the Capacitor value (Farads)
CVoltageRating is the voltage rating of the capacitor (V)
Fm is the test frequency (Hz)
Vm is the measured voltage of the component under test (V)
Im is the measured current of the component under test (A)
N is the ratio of the step-up output transformer
Worked Example:
Using a 1:3 transformer connected to the output of an Amplifier and a Test parameter of
Vm = 440 V
Im = 80 mA
F = 50 Hz.
Find the series Capacitor needed.
C = (0.08 * 3 * 3) / ( 2 * 3.14 * 50 * 440 * 0.1) = 52.11 uF
CVoltageRating = ( 2 * 440 * 0.1) / 3 = 29.3 Volts
Therefore, a non-polarised capacitor with a value of around 50 uF and ≥ 30 V must be wired in series with the
output of the Amplifier and the drive of the step-up transformer

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 11
1.3.3 Worked Example of Chroma 61602 + Chroma A615003
The same blocking capacitor is also needed , even if using off the shelf solutions.
Consider the below example of the Chroma 61602 Amp (0-300V) and the associated A615003 300-600V
transformer accessory. In this case, the blocking capacitor is still needed
Using 50Hz, 500V, 0.3Amps, as test conditions, and 2:1 for the step-up ratio of the A615003, the capacitor
need is 76uF, 50V
In this case we have used a general purpose, commonly available KEMET - R60EW61005000K 100 µF, ±
10%, 63 V Capacitor.
When writing the AT test program ATP file, a gain of 84 should be used for the external source set up, as this
represents the entire system gain
(CT10-20 module not shown fitted, but will be required)

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 12
1.4. CHOOSING STEP-UP OR STEP-DOWN TRANSFORMER
A step-up or step-down transformer can be used to boost the voltage or current of the AT5600’s own
internal 270V 2A 25 W AC source.
A step-up or step-down transformer provides good control but cannot boost the power available from the
AT3600/AT5600. Using a good quality toroidal transformer, it may be possible to provide 540V @ 1A or 135V
@ 4A, for example, but only at up to 25 W.
To give you most flexibility, and enough overhead on the step up, it is best to use a transformer with 1:3 or
better step up. This means that when requesting the maximum 600 V AC output, the internal 270V AT56
supply will be only driven to 200 V AC into your chosen step-up transformer.
The AC Interface also contains blocking capacitors in this mode, to minimise any DC on the transformer input.
Please note that the programmed turn ratio on the AT Editor program should be roughly accurate but does not
have to be exact, as the AT will constantly measure the applied output of the AC INTERFACE and constantly
trim the input to the step-up transformer during the test to give your requested steady test conditions.

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 13
1.4.1 Tip: Using multiple step-up transformers
The simplest, easiest choice of step-up transformer is as above – a 1:3 transformer, with a 200 V rated
primary, and 600 V rated secondary
However, if a 600V rated transformer is not available, it is also possible to use multiple step-up Transformers,
with the primaries in parallel or series, and all the secondaries in series.
Again, the VA rating of each must be suitable (in both cases, the load will be shared across the transformers) ,
and you will not be able to generate more than the 25 Watts power from the AT56/AT36.
Ideally, you want to
A, drive the primaries from the AT36/56 class D (10-270V) at around 50-150 Volts, so that there is enough
resolution for the unit control to trim he input to accurately give you the desired output
B, have 10% overhead on the output so that the step-up transformers you are using do not saturate – i.e., in
the largest case, having a 660V capability where the max output ever requested would be 600V
C, Ensure the step-up transformers you use are suitable for the frequency you wish to generate.
Consider the two below examples of the two methods.

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 14
Primaries in Series, Secondaries in series
3 off 24 – 230 transformers were used.
The 3 x 24 V Primaries are in series, so that the input voltage would be comfortably above 50V, up to a max
on 72 Volts
The 3 x 230 V secondaries are in series – giving 690V output
This can be considered (and programmed into the editor as “At output + Transformer) as a 72 – 690 V
transformer with a gain of roughly 9.6
Each Transformer is 15 VA rated, so the whole step up is 45VA rated, so good for about 65 mA

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 15
Primaries in Parallel, Secondaries in series
3 off 110 – 230 transformers were used.
The 3 x 110 V Primaries are in parallel, so that the input voltage would be comfortably above 50V, and with
110V max
The 3 x 230 V secondaries are in series – giving 690V output
This can be considered (and programmed into the editor as “At output + Transformer”) as a 110 – 690 V
transformer with a gain of roughly 6.3
Each Transformer is 15 VA rated, so the whole step up is 45VA rated, so good for about 65 mA

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 16
1.5. SUMMARY OF ADVANTAGES &DISADVANTAGES
Source Type Advantages Disadvantages
AC source configured as
power amplifier
Simple in use; no set-up errors
Controlled turn-on for reduced
inrush current
Trimmed output voltage
Flexible voltage and frequency
Cost of the source
Output transformer Simple in use; no set-up errors
Controlled turn-on for reduced
inrush current
Trimmed output voltage
Flexible voltage and frequency
Power limited to AT3600/AT5600
generator maximum (25 W)

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 17
1.6. OPERATING DESCRIPTION
The basic power circuit of the AC Interface provides connections on 4mm sockets for the output of the chosen
source, a series current sensing device and output to the winding under test.
Test current flows from the external source into the fixture and out to the winding under test via an isolation
relay.
The current returns through the fixture via another relay and a current sensing transformer or shunt that must
be fitted to the interface.
A standard 1:20 current transformer is supplied with each interface which should be suitable for most
applications.
The ’CT Input’ sockets on the fixture should be connected to the secondary of the current transformer, so that
the AT3600/AT5600 can measure the current in the winding under test. When a resistive shunt is used, the
'Shunt Sense' sockets provide a voltage output that is proportional to the current. These terminals must be
connected to nodes 17 and 19 of the AT3600/AT5600 if a resistive shunt is used.
The ’AT Transformer Drive Output’ sockets are used to drive a step-up or step-down transformer when that
type of source has been chosen.
The cable fitted to the ’AT Peripheral Port’ gland must be fitted to the peripheral port of the AT3600/AT5600.
This port supplies power and control signals to the AC Interface.
Control signals for an external source are available on the connecter next to the gland marked ’To AC
Source.’
Full details of each function are contained in the technical information section of this manual
Input from
External
Source
Output to
Winding
Under Test
Current Transformer (CT) or
Shunt
i

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 3 PAGE 18
2. INSTALLATION
2.1. GENERAL
1. Switch off the AT3600/AT5600 and remove any test fixtures.
2. Read and adhere to the safety information section of this manual.
3. Fit the AC Interface Fixture to the rear of the AT3600/AT5600’s top platter and twist down the locking
knobs.
4. Connect the lead 'To AT Peripheral Port' to the peripheral port of the AT3600/AT5600 at the rear of
the tester.
5. Fit the desired current CT. Normally, you can just fit the supplied Voltech CT10-20 current
transformer. For details, see the technical information section of this user manual.

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 19
2.2. POWER AMPLIFIER OR SOURCE WITH ON /OFF CONTROL
1. Switch off the power amplifier or AC source.
2. Connect the power output of the AC source to the sockets marked 'Input from External Source',
using the red and black leads supplied. Observe the polarity of the connections. The source low
should be connected to the black socket using the black lead.
3. Connect the control inputs of the AC source to their respective outputs from the interface via the 'To
AC Source' connector. The ESE line is an enable or on / Off control; ESD is the AC control signal for
the amplifier. At least one of these controls must be connected for this mode to operate without
causing damage. See the technical information section of this manual for details.
4. Connect the 'External Source Output to Fixture' sockets to the test fixture using the red and black
leads supplied. These are the leads that have 4mm plugs at each end.
Example Wiring: Power Amplifier or AC Source

VOLTECH AC INTERFACE USER MANUAL 98-072 ISS 7 PAGE 20
2.3. AT OUTPUT TRANSFORMER
1. Connect the primary of the transformer to the sockets marked 'AT Transformer Drive Output', using
the red and black leads supplied.
2. Connect the secondary of the transformer to the sockets marked 'Input from External Source', using
the red and black leads supplied.
3. Connect the 'External Source Output to Fixture' sockets to the test fixture, using the red and black
leads supplied. These are the leads that have 4mm plugs at each end.
4. For operator safety the ‘Output Transformer’ +Leads must be ether: -
a) Positioned within the Light Curtain safety enclosure.
b) Positioned outside the Light Curtain safety enclosure, in metal earth-bonded housing, using High
Voltage connecting leads.
Example Wiring: AT Output Transformer