[RE-wrenches] Megger Testers

[Howie Michaelson]

Hi Bill,

Other than good resolution for a lower range of resistance to ground, are
there any other bells and whistles for a Megger Tester that you'd suggest
or recommend?

Thanks,
Howie
-- 
Howie Michaelson
NABCEP Certified Solar PV Installer™

Sun Catcher, LLC
Renewable Energy Systems Sales and Service
VT Solar & Wind Incentive Program Partner
http://www.SunCatcherVT.com
(cell) 802-272-0004
(home) 802-439-6096


On Mon, April 13, 2009 8:17 pm, Bill Brooks wrote:
> 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.
>