Problem testing a iKasu 6 Socket Surge Protector

[gaz]

I need some help, I am using a PrimeTest 350 and I am having a problem with a particular model of surge protection lead as shown on this website.

http://www.fascin8.co.uk/f8/ikasu/45-miscellaneous/166-ikasu-6-socket-surge-protector-dm076821

When I run any test for “surge protected leads” on these leads, the PrimeTest 350 gets as far as the "Insulation Test" before failing the appliance. At a point during the Insulation test the lights near the sockets on the lead flash (as in explanation "B" on the website given) the meter reads around 24Mohm and the PrimeTest fails the appliance.

I have 6 of these leads to test and exactly the same thing happens on all the leads which makes me think that it can’t be the leads.

Removing the “insulation Test” results in a pass, but I am concerned this is not an acceptable practice and won’t pass the leads until I have asked opinion from my peers (that’s you lot!).

Your help and advice will be gratefully received.

[Patnik]

24 megOhm at 250V is fine - surge protect and filtered leads quite often give a reading less than the open circuit >99.99 megOhm you get with 'everyday' leads, it's just the componetry between the live conductors and earth.

According to the CoP a fail for class 1 insulation resistance is <1 megOhm and these are way above that, the test sequence settings seem over cautious if they treat 24 megOhm as a fail.

I'd pass these presuming other test results, visual inspect, BS markings etc are all in order. I wouldn't just skip the insulation test though, I'd accept the 24 megOhm reading and change the result to pass (or even better edit the test sequence).

Nik

[gaz]

Thanks for that, it goes a long way to confirming what I was thinking.

Unfortunately as I don’t fully understand what the PrimeTest 350 is doing I am not confident enough to change/write a new test programme to allow it to pass the leads. I can copy and alter test parameters to configure new tests but I don’t have a clue what to programme to get over this 'fail'. Once the tester has failed the appliance there is no way to tell it to pass it and move on. Therefore I must find a way to programme a test that will both pass the leads but remain a ‘safe’ test.

[Patnik]

Looking at the manual online (http://www.pattesters.co.uk/resources/files/primetest-350-manual-45.pdf page 108) it seems to say that the default setting for insulation fail is <1 megOhm, as it should be, and that the maximum is 10 megOhm implying that setting it above 24 megOhm is impossible. I can't think why anyone would want to set it that high, 2 megOhm maybe as that used to be the limit. The manual shows how to change fail limits but you need to have admin access.

Are you quite sure it is reading 24 megOhm - not kiloOhm? Perhaps it's faulty, have you tried using the surge protect sequence on a known good (not surge protect) lead? I've not used a Primetest but our Europas come up with some weird faults.

Nik

[gaz]

There is every chance I could be reading the Ohm's wrong!

I have submitted the question to the guys at Seaward, I will report back when i hear more.

[verstapp]

or perhaps its a manufacturing fault. someone here got a bunch of cheap, 'fell off the back of a truck', surge protected powerboards [multi-socket outlets]. 'but i suppose i better get them tested before putting into service'. local electronics workshop puts it on a supernova, 'short circuit at 240V'. megger@240V - short circuit. i happen to be passing with my primetest 300, 'here, come test this!' same result. they told the purchaser to bin the lot and go buy some proper ones.

i came up with a theory - say you're a factory in china churning out a million of these a month. your MOVs arrive by the lorryload. you have 2 main streams - 120V and 240, possibly with substreams for UK/Oz markings and sockets. a new lorry driver pulls up one day with a load of 120V MOVs, happens to pull into the wrong bay. with the comprehensive quality control that modern factories are known for the MOVs enter the 240V stream and exit in the finished product, and no-one's the wiser... until their powerboard starts melting soon after being plugged in. the electronics workshop mentioned above says this is entirely plausible as it gets to repair all sorts of equipment where this sort of error has occurred. and not just $3 chinese powerboards but $100,000+ items of scientific equipment as well.

[Inspexx]

All surge protected devices will fail the Insulation Resistance test.

The test puts 500v DC into the aut. Surge protected devices have an upper limit of around 300v, hence the fail.

You should use the Alternative Leakage test instead.

[Alan Freeman]

Inspexx.

If you re-read the question "When I run any test for “surge protected leads” which should set the tester to 240v!

[verstapp]

and my answer says 'tested@240V', not 500.

[gaz]

Thanks for the input so far guys, with no answer forthcoming from seaward I find myself in limbo here.

I am pretty sure now that PrimeTest 350 reaches the ‘Fail’ point when the circuitry in the surge lead detects that the Line and Neutral conductors are connected together for the "insulation Test”. I believe it is at this point that the surge lead trips a relay and opens the circuit to stop any potential damage; the PrimeTest now sees an open circuit and fails the test.

The problem now becomes how to tell the tester that its ok, it’s meant to happen and to pass the lead.