battery monitor?

[jamesdestin]

Ok so, on impulse I bought this battery gauge "thing" on ebay. Looks very basic, just a needle and a scale with red yellow and green on it. No instructions, no shunt. Is it likely to be of any use or will whatever it tells me be so limited in value that I'd be better off putting it back on ebay?

 

[fluffc]

It'll be good to tell you the basics - ie battery fully charged, okay, or dead. Won't be of use to tell you how much charge is in them as this either requires an Ah meter or very sensitive voltmeter.

To use, just connect across the positive and negative terminals of the battery. Some clever wiring with a two-way (on)-off-(on) switch will allow you to check both batteries, and keep the meter disconnected (preventing battery drain).

 

[William_H]

Yes but also it is a very good inndication that the batteries are being charged. No not a compolete waste of money (but nearly) olewill

 

[AndersGu]

When I bought my boat back in 1996, I rummaged through the junkbox and found an unused "meter". I added a zener end some resistors so that it now displays between 9 and 15V and calibrated it and made a nice coloured scale. It is fairly accurate. It also shows whether you are charging, ie voltage rises as the solar panel is illuminated.

 

[jamesdestin]

Thanks guys, I'm planning a fairly simple system so I think I'll give it a go