ZS testing

[clematis432]

Hi, I,ve got my City and Guilds 2391 but have done little "hands on" testing till now.
When ZS testing, eg a fluorescent lighting circuit, and testing at furthermost light fitting, is it OK if fluorescent light fittings are switched on when the test is being carried out ? I don,t think the vulnerable components in the fitting would be damaged by the test current but would like to be sure. It would be impractical to disconnect all the fittings from this circuit.
Thanks in advance,
Wullie

 

[ezzzekiel]

no it would show up as a dead short on your tester

 

[jamie-spark]

i think you are getting confused or had a typo Zs is a live test, so you need the circuit to be energised to test.

 

[jamie-spark]

maybe you mean an insulation resistance test

 

[ezzzekiel]

i did sorry must of been miles away

 

[telectrix]

a Zs test would be OK with fittings connected, but for IR test, if you can't dis. them short L/N and test to cpc @250v. ( soft test. )

 

[ezzzekiel]

no damage will incur during the Zs testing however for accurate results all items of equipment should be disconnected.

 

[telectrix]

but, in a real situation, the protective device relies on the circuit Zs with all loads connected. admiitedly, it is better to disconnect loads for testing purposes, but sometimes impractical. suppose a house has several floodlights outside, 15 ft. up. would you go round removing all the lamps? i certainly wouldn't.

 

[ezzzekiel]

I agrees with him above, seems to know what hes talking about and yes in real life you prob wouldnt disco everything but if you follow testing procedures then prior during your Ir testing most thinks will of been disconnected anyways.

 

[clematis432]

Thanks gents, can I now assume that no damage can be done to any loads connected during test especially to "vulnerable components"
Thanks again.

 

[telectrix]

no damage when performing Zs test. IR test is a different kettle of sardines.