[RE-wrenches] Megger Testers

[Bill Brooks]

Kingsley,

 

The concern I have about this unit, and many other inexpensive ones like it, is that it does not have enough resolution in the low impedance area. PV arrays can have an impedance to ground of as low as 2kOhms. A resolution of 0.1MOhms will likely not cut it. I just bought a $175 meter for fun and I will take it out into the field to try it next to the Fluke 1520. If we can get decent information, great. But the better resolution may require spending closer to the $700 or more. 

 

The key is that you don’t want to be chasing a ground fault that really does not exist. The resistance to ground can be so low that a simple meter will call it ground-faulted. I’ll let you know what I find out. I’m betting that megger testing PV arrays is about to get required much more regularly.

 

Bill.

 

From: re-wrenches-bounces at lists.re-wrenches.org [mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Kingsley
Sent: Saturday, April 11, 2009 9:24 PM
To: RE-wrenches
Subject: Re: [RE-wrenches] Megger Testers

 

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