Thought i’d quite like a battery monitor to keep an eye on the state of the battery and to check that the alternator is working correctly and not over charging…
So bought this item from ebay (200547996513) and thought about how to mount it inside the car…
Have got a switch blank and thought i could fit it in there - so with a bit of fettling i managed to fit the battery/charge monitor into the blank switch surround
The unit comes with 3 wires red/blue/yellow
Connecting the blue wire to earth and the red wire to a permanent live i now have a fully functioning battery/charging monitor!
I didn’t connect the yellow wire to give a bar graph type display as i only wanted 1 led to indicate the battery/charge state.
Using 1 led it only draws 2ma - so won’t have a big drain on the battery.
Led colours indicate voltage:
3RD GREEN 12.5V +
2ND GREEN 12.1V
1ST GREEN 11.8V
YELLOW 11.5V
ORANGE 11.2V
RED 11V
RED (FLASHING SLOW) 10.7V
RED (FLASHING FAST) 10.5V
It also indicates over charging by flashing the 2 end led’s (red and green) at 15.2v
Its not an advert for the item or the seller - but i think its a really good looking mod - especially if you have a switch blank!!
I have fitted a similar but simpler device to many of my bikes - I can’t find it on eBay at the moment, but it is a single LED (like a warning light) which lights up green/yellow/red in various sequences for different voltages. Very discreet, about the size of a penny, and reassuring when you are a long way from home and your battery is only 10AH in size. I was looking for a clock-style voltmeter for the 5 but couldn’t think of where to mount it, but then I saw this on Amazon:
Very simple, just plugs in the cigarette lighter socket. At less than £1.50 delivered, I bought one for each car. I won’t be keeping them in all the time, but it’s nice to be able to check battery resting voltage and alt output every so often. I expected junk at that price, but in fact they seem well made and work perfectly.
I bought the one Zulu recommends. It is excellent. I find it interesting to see how the voltage changes with load and battery charge. The only comment I would add is that, as it measures the voltage at the lighter socket, it reads a little on the low side when the engine is not running. Possibly due to voltage drop along the wiring and any “dark” drain.
