CURRENT INJECTION TEST

Hello Guest,

It is not safe practice to current test your Control Panel, unless the Generator is OFF at the time.

Run your test set from a small portable generator if you cannot obtain a separate Mains Supply for the test Set.

Using an auxiliary 220V Supply, operate the Under-Voltage coil, so that the Breaker remains ON.

Please note that the MEGGER PCITS2000/2 Test Set does have an auxiliary output which can be used to operate the UV coil.

Remember that the "Current Injection" Test is normally done at a low actual Voltage, sometimes via a special transformer from the Test Set if the Test Set current output is insufficient - You are at that point not Voltage testing the Control Panel, you are Testing Current Operation.

There should normally be an Operator's Manual with your Test Set, plus a second one in your organisation's Engineering Office (That is the back-up copy of the two Operator's Manuals supplied with the Test Set)

<"....From: http://www.megger.com/aen/products/ProductDetails.php?ID=323&Description=

Products : Power : Relay Test Equipment :

MEGGER PCITS2000/2 Primary Current Injection Test Set • Test relay protection systems and their current transformers together • Current level maintained though test circuit resistance may rise due to heating • Built-in timer to record protection relay operation

This Primary Current Injection Test Set is rugged, self-contained and designed for operation by one person. The PCITS2000/2 is a two-wheeled unit (with a handle). The test set has a separate hand-held controller connected by an expandable cable. This allows the operator to work close to a protective relay while controlling a test. The maximum output current is 2000 A a.c. at line frequency. By changing the range switch, half the rated output can be obtained at twice the voltage. Additionally, a separate auxiliary voltage output of 250 V, 2 A a.c. or 125 V, 2 A a.c. is available for testing voltage operated relay coils or checking the magnetisation characteristics of current transformers. All outputs are fully variable and each test set has a nominal duty cycle when delivering full current and voltage. Continuous operation is possible at 40% of maximum current.....">

If you need further assistance, reply with

Kind Regards....

hi spark station:

thanks for these usefull informations, is this tester use for the breaker wich equiped with CTs inside only or it can be done for thermal protection breakers.

can we use this tester for low amps breakers same as on MCC panels?

best regards

Hello again, "Guest".

I have not personally used this particular Test Set, but it should be capable of small output to check both thermal protection Breakers and MCC panel Breakers.

Check minimum output current first :

You would need to check the unit, and ensure that the testing current did not overheat the equipment being tested, and this may be done by a short circuit test, starting at the minimum output current setting, and taking careful note of the current at that setting.

If this minimum setting did not exceed the rating of low amps breakers, you would also be able to use it on MCC panels, along with thermal protection breakers.

If the minimum output current was too high, then use a Variac on the Mains Input to the Testing Set, but if you needed the 220v for any UV relays, you would need to use that 220V as supplied NOT VIA the Test Set, because if you used the Test Set auxiliary 220V output, that would be varied via the now Variac controlled Mains Input to the Test Set.

Trust that assists you.

Kind Regards....

HI AGAIN;

i tell you what we did exactly:

we have 3phase 125A thermal protection breaker, i connected the tester current leads on one phase only, one to the input and the other to the output of the breaker and injected up too 550A but it did not trip even after 2minutes.

today i tried on 1600A GE circuit breaker equiped with CTs and trip unit, i did the same connection of 125A breaker and injected up to 1750A for about 1minute but no thing happened.

is the connection which i did right or i should pass the current leads through the three phases on series?

if i will do secondary test for the CT of the GE breaker should we inject ''instead of the CT'' 5amp to the trip unit to make it functioning?

i am trying to get an answer from you before you go to sleep as your place is in the far east, my time here is 8:00AM, but yours?

many thanks

Hello again, Guest,

You have not advised the Make and Model of the 3-phase 125 amp thermal protection Breaker, thus I do not know the tripping curve for that unit.

To check 3-phase thermal circuit Breakers, test each phase singly = 3 tests one per phase.

I do know some test technicians "cheat" by running the 3-phases looped in series, but that is not the proper test for a 3-phase circuit Breaker.

Your 1600amp GE circuit breaker equipped with CT's and trip unit, likewise I do not have model of breaker, thus likewise I am unable to see the tripping curve.

If you know the Make/Model of each Breaker, obtain the tripping curve from the Maker - generally this should have been supplied for each item with brand-new equipment.

If you have new equipment, insist the supplier sends you the technical data for each item, this would include full Specifications for each item (and for circuit Breakers the tripping curve also).

The tripping curve shows a graph of current/time, and the Breaker as tested should be closely aligned with the various points on the Tripping curve, which then proves it is to Maker's Specifications.

If you are unable to obtain the technical information locally, obtain from the Maker via their website/s, generally in .PDF format, for which you need Adobe Reader (Acrobat) Software installed in the viewing computer.

If you have purchased new equipment, and the supplier does not want to supply you with the technical information of each item (it would have been supplied by the Makers with each new item) then seriously consider using a different supplier for your next purchase/s.

Advise further, if you need help, with

Kind Regards....

HI:

YESTERDAY WE GOT THE BREAKER WITH CTS TRIPPED ON 1600AMPS, WE FOUND THE PROBLEM WITH THE TRIP UNIT, MICRO VERSA TRIP UNIT ''DIGITAL''.

ITS GE BREAKER CAT NO# THP1616TTC 1600A 3POLE

BUT THE THERMAL BREAKER DID NOT TRIP EVEN AFTER 10MINUTES WHEN WE INJECTED 125AMPS THROUGH 1P0LE ONLY.

ITS GE BREAKER CAT NO#TCAL15 TYPE#THCL136125 600VAC 125AMPS 3POLE

JUST ONE MORE QUESTION:

IF I WILL DO THIS PRIMARY CURRENT INJECTION TEST FOR THE MAIN BREAKERS WHILE THEY ARE CONNECTED IN THE PANEL AND THERE SOME CONTROL EQUIPMENTS CONNECTED WITH THE CIRCUIT, SHOULD I DIDSCONNECT THEM OR JUST CONNECT THE TESTER LEADS TO BOTH SIDES OF THE BREAKER AND INJECT THE CURRENT?

MANY THANKS

Hello Guest,

In case you did not know, using ALL CAPITALS in an Internet Forum is regarded as shouting loudly in the reader's ear, and thus as bad manners.

Perhaps your ALL CAPITALS problem is caused by having the Caps Lock button switched "On" at your computer.

<"....YESTERDAY WE GOT THE BREAKER WITH CTS TRIPPED ON 1600AMPS, WE FOUND THE PROBLEM WITH THE TRIP UNIT, MICRO VERSA TRIP UNIT ''DIGITAL''.

ITS GE BREAKER CAT NO# THP1616TTC 1600A 3POLE

BUT THE THERMAL BREAKER DID NOT TRIP EVEN AFTER 10MINUTES WHEN WE INJECTED 125AMPS THROUGH 1P0LE ONLY.

ITS GE BREAKER CAT NO#TCAL15 TYPE#THCL136125 600VAC 125AMPS 3POLE....">

Because I do not have a copy of the "Tripping Curve" for that equipment, I am unable to comment on the Current/Time you quote above. You will need to obtain the Specifications, including the "Tripping Curve" from the Equipment Makers.

<"...ONE MORE QUESTION:

IF I WILL DO THIS PRIMARY CURRENT INJECTION TEST FOR THE MAIN BREAKERS WHILE THEY ARE CONNECTED IN THE PANEL AND THERE SOME CONTROL EQUIPMENTS CONNECTED WITH THE CIRCUIT, SHOULD I DIDSCONNECT THEM OR JUST CONNECT THE TESTER LEADS TO BOTH SIDES OF THE BREAKER AND INJECT THE CURRENT?

MANY THANKS....">

Because I do not have the full schematic of the switchboard and equipment installed, it would be unwise to advise you to test with other equipment connected.

Thus to check any Circuit Breakers, disconnect them from other equipment and test each phase separately as I advised in an earlier Post.

Kind Regards....