Club 80-90 Forums

Sometime in his previous life, Keif had 2 volt meters fitted. One for the main battery and another for the leisure battery.

Unfortunately, they are on permanently and therefore always taking power. Can anyone point me in the right direction to sort it so that they only indicate the power in the batteries when the ignition is on.

TIA

A manual switch is whats needed

Also depends what kind of voltmeter. My digital one draws so little it doesn't matter.

I fitted one of these http://www.ebay.co.uk/itm/RS-12-miniatu ... 43ca414c51" onclick="window.open(this.href);return false; wired it to the ignition and the supply to each meter switched seperatly. Works bril.

Simple relay ........

Verne wrote:Can anyone point me in the right direction to sort it so that they only indicate the power in the batteries when the ignition is on.

Aye, but bear in mind, when the ignition is on (and motor running) the two batteries are connected together and so the readings will / should be the same on both. However, you may well want to know the state of the leisure battery when the ignition is OFF, ie when actually using it

If your meters are pulling too much current (and as Ralph says, some don't) then, for the leisure one, a simple "push to make" button type switch (Maplin/Ebay etc) would be a good idea.



And for the main battery one, simply find a wire that "comes live" when the ignition is on. The feed to the headlight switch could be used, though it could read a bit low when the lights are on. Or, as Mocki says, you could fit a little relay, and if you are careful where you take the feed to the meter from (separate wire from battery is ideal) then that would give the most accurate reading

I've used one of these from RS.



In position 'I" it shows the starter battery, in position 'II' it shows the leisure battery, and in the middle ('0') position it's off.

That is very good

But, Verne has two meters already fitted, so the wiring of such a switch does not lend itself (easily) to such a set up (unless removing one of the meters is an option ?)

ghost123uk wrote:

Verne wrote:Can anyone point me in the right direction to sort it so that they only indicate the power in the batteries when the ignition is on.

Aye, but bear in mind, when the ignition is on (and motor running) the two batteries are connected together and so the readings will / should be the same on both. However, you may well want to know the state of the leisure battery when the ignition is OFF, ie when actually using it

If your meters are pulling too much current (and as Ralph says, some don't) then, for the leisure one, a simple "push to make" button type switch (Maplin/Ebay etc) would be a good idea.



And for the main battery one, simply find a wire that "comes live" when the ignition is on. The feed to the headlight switch could be used, though it could read a bit low when the lights are on. Or, as Mocki says, you could fit a little relay, and if you are careful where you take the feed to the meter from (separate wire from battery is ideal) then that would give the most accurate reading

If you wire it as I suggested,
With ign on but not started. You get both bat voltages as they are not connected together no split charge connection
With engine running. You are checking both batts are charging

ghost123uk wrote: But, Verne has two meters already fitted, so the wiring of such a switch does not lend itself (easily) to such a set up

Oops - missed that!

nicq wrote: If you wire it as I suggested,
With ign on but not started. You get both bat voltages as they are not connected together no split charge connection
With engine running. You are checking both batts are charging

This is true, but you would not get a reading from the leisure battery when you most need it, ie when parked up camping.

Thanks guys, I like the push button option for the leisure battery, so may try a combination of relay and button - if I can get it right in my head

Just to verify the relay idea, it's there so the meters only get powered when the ignition is on? And this to eliminate any power consumption when laid up?

Are folks using two wire or three wire versions? The Chinese translation didn't really explain the third wire clearly :s

The 3 wire ones are for when the meter is going to be asked to read voltages well away from 12 Volts. The main power wire supplies 12 Volts to run the circuits, the other wire monitors the voltage you wish to read, which can be say 3 Volts, or maybe 30 Volts etc.