Earth (ground) fault locators for unearthed (ungrounded) DC systems

[ScottyUK]

The old Biccotest T273 unit I am familiar with appears to be out of production, so I'm looking for a modern equivalent to purchase. I'm considering a couple of possible instruments and wondering if any of you have operational experience with either of these types?

Megger BGFT battery ground fault locator

http://www.alpha-electronics.com/Items/8779/246100b.html

Seba Geolux GL660

http://www.alpha-electronics.com/Items/809/seba-geolux-gl-660-1.html

Links are to a UK distributor just for convenience more than anything.

 

[ScottyUK]

Another possibility:

http://www.bender.org/documents/NAE1012030_datasheet_EDS3090.pdf

I have used some really poor earth fault locators in the past, and keen not to repeat the experience.