IR test method 2

[james king]

is this test exepatble and does it bypass tranny and bulbs ect? i have been told on here befor ye so i am just wondering

 

[telectrix]

it is acceptable when by performing method 1, you might damage equipment which you are unable to disconnect. e.g on a PIR/ for a new install, on initial verification, you would always use method 1, as in that case there would be no loads connected at the time of testing.

 

[james king]

sorry i dont understand that? i thought method 2 was used when it was nearly inpossible to dissconnect some equiptment eg bulbs and trannys also neaons??? can u leave them in and use method to to bypass the equiptment?

 

[telectrix]

suppose you had a load of high bay lights 25 ft. up in the air. would the client pay for the hire of a cherry picker and the time to remove the loads for you to test?

 

[james king]

depends how rich thy are lol, prob not so there for am i rite in says it does by pass the bulbs?? a simple yes or no would help haha

 

[telectrix]

yes it does. because you are shorting out L/N and testing from there to E. therefore, you are not applying the test voltage across the load.

 

[james king]

ahh thnk u i understand now!! so say u get a reading of 0.00 using method 2 then there is for sure a fault with the cct, as the loads have been bypassed

 

[telectrix]

definitely. some appliances e.g. computers have high earth leakage currents, but only around 3-4mA, so would still give you a reading L/E of around 80kohms at250v.

 

[james king]

great, thank u very much for ur help. now i am correct in saying that 0.00Momhs is a dead short right? or close to one

 

[mayfair]

as near as you can get. Remember to check your leads are OK before doing the test as you could think you are performing the test when actually you are just getting eroneous (spelling) readings.

 

[telectrix]

good point. also a good idea to get an apprentice to hold the lead ends to ensure you are actually getting a voltage output.

 

[Voltimax]

0.00 Mohms doesn't always equate to a dead short reading. If you have any surge protectors connected to the circuit(s) under test, they will give you that reading when using the method you refer to. You must therefore disconnect them, or if that isn't possible, reduce the testing voltage to 250V, making sure you have noted this on your report.

 

[mayfair]

find plasterers are useful for that..........

good point. also a good idea to get an apprentice to hold the lead ends to ensure you are actually getting a voltage output.

 

[james king]

so using method 2 wouldnt by pas surge protectors? were would u usally find these?

 

[telectrix]

usually on electronic gear, pc's, tv's, power dildos .......