PAT testing a 415V appliance

[ringer]

Have been asked to PAT test a 415V steam cleaner. Not seen it yet, but likely to become acquainted with it next week. Not had any industrial experience, so 415V 3-phase is new to me.
Am trying to plan how I can test it - it will have a 415V plug on it, but not sure if it will be star or delta (or will it not matter, socket wise?). I have a Fluke 6500 and a Megger 1552.
Am looking for suggestions on what socket to buy, how to connect the terminals, and what tests I can realistically do. Is it possible to do a satisfactory test with the equipment I have?

 

[ringer]

Did the job today - it wasn't an official PAT test, more a safety check on an appliance that may or may not work. The appliance was passed on to owner as a spares or repair project because it had previously failed an earth bond test when another company PAT tested it. I soon sorted that problem out - no earth connection because where flex was connected to the machine, the earth connector was gripping the insulated part of the ferrule instead of the uninsulated part of it. Had probably been like this from the factory! Official PAT test is to be completed once appliance is up and running - owner has not got a 415V socket in his installation at the moment.

I bought a 32A connector socket but didn't use it in the end. Didn't use the Fluke 6500 either. Opened up the plug to see how it was wired and to check connections. Then checked the earth bond with Megger 1552. Then clipped the three phases together (there was no neutral), and put one test lead on phase and one test lead on earth, and IRed first at 250V then at 500V. Was satisfied enough with results to not throw 1000V at it. Was unable to run it to do load test because supply not available yet.

In writing this I realised I should have wired a 13amp plug to the 32A connector and done a proper Earth Bond at 25A with the Fluke 6500. Will go back and do this tomorrow.

connections for 32A connector to 13A plug:
(32A) L1+L2+L3 --> (13A) L
(32A) N --> (13A) N
(32A) E --> (13A) E
This for Earth Bond and IR test using Fluke 6500.
Note for IR test - always check internal wiring on appliance plug to ensure wired as expected.

Also need another 32A connector socket and 32A plug to make up a mini extension lead
L1 --> L1, L2 --> L2, L3 --> L3, N --> N using four-core flex
E --> E in single run parallel to the flex, but with some slack.
That way can put a clamp meter round the earth and measure earth leakage when the appliance is running. Will not be able to do full load test because unable to measure drawn power. Could possibly wire this lead completely in singles and group together L1+L2+L3 so can measure drawn current, then calculate power consumption.

Ideally would also have another 32A plug connected to a C13 IEC female
(32A) L1+L2+L3 --> (C13) L
(32A) N --> (C13) N
(32A) E --> (C13) E
this to be used in conjunction with the first lead above (the Earth Bond and IR lead) to test 415V extension leads

That's a lot (about £50 worth) of 32A connectors/plugs to buy!

Of course, all readings obtained need to be interpreted making reference to the Code of Practice.

Detailed this as a sort of reminder to self and hopefully help others unsure how to test 415V appliances.

All above is based on my own assumptions about how to do this properly, and I stand to be corrected if any of it is incorrect or could be done better.

 

[ringer]

Discovered that Seaward are developing a special adaptor to be used in conjunction with their Primetest 250 model, so asked them the question:

"I was under the impression that the only way to measure 3ph leakage was using a clamp meter on an exposed earth cable whilst operating the appliance. Your data sheet states that it requires a three-phase adapter accessory and uses the 3ph supply voltage. Could you please explain to me what the internals are to the adapter in question (I already have 3ph adapters for measuring earth bonding and insulation resistance), and how the tester actually does this differential leakage test?"

and the response I got was:

"Your correct in that the traditional approach to measuring leakage on 3 phase equipment is to place a suitable clamp meter around the protective conductor. There are some limitations with this method, not least the fact that you require access to the protective conductor.

We have developed a new range of accessories for the PrimeTest 250 for measuring both earth continuity and earth leakage. There are 4 adaptors available for 16A and 32A with either 4 pole or 5 pole connectors.

The adaptor is fitted with a 3 phase plug and socket and is connected directly to the 3 phase outlet and the 3 phase equipment is then connected to the adaptor. The adaptor sits in line with the supply to the 3 phase equipment allowing it to measure the current flowing in the protective conductor. The adaptor is also connected to the PrimeTest 250 and the LCD is used to indicate the measure protective conductor current in real time. The fact that we have a connection to the protective earth in the 3 phase supply also allows us to measure the earth continuity.

I hope this is clear.

Best Regards
Jim

Jim Wallace
Product and Technology Manager
Seaward Electronic"

An interesting development, but I wonder what the cost of these adaptors will be?

 

[malcolmsanford]

I wonder why the 50p an item merchants never undercut you on that one ringer?

 

[msad-0112]

Thank you very much mate, these are realy valuable information

regards

 

[i=p/u]

So the likes of my kt71 it carries out run and leakage test .
So if I used a 3ph adapter linked internal this would blow fuse

 

[i=p/u]

This is one fir oldtimer

 

[i=p/u]

Elllllllooo

 

[JCE]

The I.E.T have updated there code of practice for in service inspection and testing of electrical equipment priced at £55 pounds its due out soon , however it sounds like jim wallace is on the ball , cheers

 

[i=p/u]

SOUNDS like they can go scratch