Application Note - High Current With 3 CP CB2

Markus Ptter Subject

OMICRON electronics 2008-06-05 1/6

Generation of High Currents with the

CPC100 and 3 CP CB2 Current Boosters

Purpose: This application note describes how to make the test setup to generate currents up to 7000A with one CPC100 and 3 CP CB2 current boosters.

Introduction: With the CPC 100 and the CP CB2 current booster you can generate currents up to 2000A. Sometimes it is required to generate more current for example to test CT's with nominal currents above 2000A. With 3 CP CB2 current boosters it is possible to power out up to 7000 A.

Safety instructions: Before starting the test the CPC100, the CPC booster box and the 3 current boosters must be grounded properly.

The current boosters must be mounted close to the DUT (Device Under Test). Take care that they are mounted safely and cannot fall down.

Operating the test with "RANGE 2" means that the CP CB2(1) and CP CB2(2) are connected to 400 V AC on the primary side. The supply voltage for each current booster is therefore 200V, which is more than they are specified for. Therefore do not exceed the test time longer than 15 seconds to avoid the destruction of the current boosters.

If you measure CT's, all other secondary terminals must be short circuited to avoid high voltages on the terminals.



Test Setup One CP CB2 is controlled through the CPC100. This is the only current booster where you can adjust the current. The second current booster - CP CB2(1) - and the third - CP CB2(2) - are connected to the CPC Booster Box. The output current of these boosters depends on the load and the supply voltage. The supply voltage can be 240 V (Range 1 phase to N) and 415 V (Range 2 phase to phase). You can connect one booster, two boosters or three boosters in parallel to the DUT. Because you do not know the primary injected current you need a reference CT (Ref CT) to measure it.

The CPC Booster Box must be supplied with a three-phase system inclusive neutral and at least 32A. Note: Due to the high current also on the primary side of the CP CB2 it sometimes occurs that the fuse in the CPC Booster Box trips. By the factory tests the maximum current could only powered out for 5-10 seconds.

1.1 Current Ranges The current ranges depend on the connection and the connected load and can therefore not be guaranteed. The following current ranges are reference values which were determined during tests in laboratory.

1.1.1 Currents from 500 2000A For this range you can use only the CPC100 together with the CP CB2. The CPC Booster Box is switched off.



1.1.2 Currents from ~2000 to ~4500A in Range 1

The supply voltage to the current boosters CP CB2(1) and CP CB2(2) is 240V. CP CB2(1) is connected in parallel with the CP CB2 of the CPC100 to the DUT. The CP CB2(2) must be short circuit.

Range 1 2000A to 4500

Test setup:

Switch to Range 1 (CPC Booster Box) Connect the current boosters to the CPC Booster Box and CPC100 and make all connections

according to the diagram below Connect the Ref CT to the I AC input of the CPC100 Configure the Ref CT at the CPC (Option view Device Setup Clamp & input transformer settings

CT) Use a Quick Card and select the output range "CB2 2000A". Select "Sync to V1 AC" and for the

measurement select "I out" and "CT" Connect the secondary side of the DUT to an additional ammeter

Executing the test: Switch on the CPC Booster Box and read the actual primary current on the CPC100 (Measurement

"CT") Switch off. If you need more current add the additional current with the CPC100. First switch on the CPC Booster Box and then the CPC100. Now read the actual primary current

(Measurement "CT") and set your primary current with the CPC100 to the requested value. Read the secondary current of the DUT at the ammeter Calculate the ratio Test finished




The supply voltage to the current boosters CP CB2(1) and CP CB2(2) is 420V. CP CB2(1) is connected in parallel with the CP CB2 of the CPC100 to the DUT. The CP CB2(2) must be short circuit.

Range 2 3500A to 5000

Test setup: Switch to Range 2 (CPC Booster Box) Connect the current boosters to the CPC Booster Box and CPC100 and make all connections




Executing the test: !!!To avoid the destruction of the current boosters do not switch on longer than 15 sec!!! Switch on the CPC Booster Box and read the actual primary current on the CPC100 (Measurement





1.1.4 Currents from ~3500 to ~5000A in Range 1 The supply voltage to the current boosters CP CB2(1) and CP CB2(2) is 240V. CP CB2(1) and CP CB2(2) is connected in parallel with the CP CB2 of the CPC100 to the DUT.

Range 1 3500A to 5000A

Test setup:





Executing the test: Switch on the CPC Booster Box and read the actual primary current on the CPC100 (Measurement






The supply voltage to the current boosters CP CB2(1) and CP CB2(2) is 420V. CP CB2(1) and CP CB2(2) is connected in parallel with the CP CB2 of the CPC100 to the DUT.

Range 2 4000A to 7000A

Test setup:





Executing the test: !!!To avoid the destruction of the current boosters do not switch on longer than 10 sec!!!

Switch on the CPC Booster Box and read the actual primary current on the CPC100 (Measurement "CT")

Switch off. If you need more current add the additional current with the CPC100. Switch on first the CPC Booster Box and then the CPC100 and read the actual primary current


Application Note - High Current With 3 CP CB2

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