[Solved] Which insulation meter should I buy? - Page 1
Forum section: electronics / testgear

author: blueskull
author_rank: Unknown
timestamp: April 08, 2017, 01:44:39 am
content: In another thread I mentioned I'm building a AC/DC power supply for my laptop (see here:https://www.eevblog.com/forum/projects/a-46win3-power-adapter-with-active-pfc/).Since I don't want myself killed, I think I should be able to test my finished product with an insulation meter.According to UL60950-1, for world wide input voltage (I mostly live in the US, but I go to China every year to visit my family), it needs to withstand 2.5kV peak transient.The transformer I used is designed for telecommunication system and is only certified at 1.5kV RMS isolation (2.1kV peak), therefore I need to test it myself to see if it will withstand 2.5kV.Is there a good insulation meter that can do 2.5kv testing? So far I know Uni-T has some cheap ones, particularly UT533 and UT502A. I'm not interested in the much more expensive UT513A. My budget is $300 or less.I don't need high accuracy -- just a qualitative test. For precision works, I have a Keysight U1461A and a Keithley 2410 SMU, but both only go to 1.1kV, even series connect them together it is still not enough to generate 2.5kV test voltage.Any recommendations? Thanks in advance.Bought UT502A.

author: boggis the cat
author_rank: Regular Contributor
timestamp: April 08, 2017, 03:05:45 am
content: You could ask an electrician to test it. Cheaper than buying your own equipment.If you want to work on the design, and possibly fix issues, then one of the cheap Chinese instruments is probably adequate. Ideally you should verify that it is doing what it should (you will need an HV probe and suitable resistive loads), just in case it isn't quite up to specification.An independent test house will have to certify it if you intend on selling this commercially -- the cost will make your eyes water. For your own use it is more a case of making sure you don't risk a fire or other problem, because insurers will use that as an excuse not to pay out.

author: boggis the cat
author_rank: Regular Contributor
timestamp: April 08, 2017, 05:37:13 am
content: It seems to me that you should just buy whatever has the features you might want within your price range. If you are able to characterise any critical usage then you should be fine with a cheaper, potentially less reliable, instrument.There are also combined DMM / insulation testers, but I don't recall any rated higher than 1 kV.

author: boggis the cat
author_rank: Regular Contributor
timestamp: April 08, 2017, 11:45:05 am
content: Quote from: blueskull on April 08, 2017, 06:00:09 amI think that only gets to 1 kV. That is what is marked on the case.

author: aargee
author_rank: Frequent Contributor
timestamp: April 10, 2017, 06:40:14 am
content: Motors, etc might be OK for 1kV testing but anything we test has sensitive electronics, we only test to 500V for leakage and that's medical.

author: flash2b
author_rank: Regular Contributor
timestamp: April 10, 2017, 07:09:30 pm
content: I have a Duoyi DY30-2, see:http://www.dyinstrument.com/duoyi/?q=insulation_resistance_tester/DY30-1/DY30-2Very similar specs as your UNI-T UT502A.