Low Volts Light

[mike newall]

Just bought a unit from Eric Jones in the US.

Under $50, plus a little shipping - much cheaper than alternatives, works really well - good snap fit, discrete unit, great value for money and fast delivery.

I'm not connected with him, just super impressed with his gear - check out his website.

http://www.periheliondesign.com/

[Rob Swain]

Looks better value than a lot I've seen.

If you are handy with a soldering iron and a few elctronical bits then you can build one for less than a fiver including a box to put the gubbins in. The other advantage is you get to pick the lamp to put on the dash. Mine matches the starter and fuel pump warning lights (I know - but I used to keep leaving it on!).

Admittedly mine doesn't flash, though!

[John Dean]

I know - but I used to keep leaving it on!)

Been there, done that!! Now have the largest, reddest light I could find right in the centre of the instrument panel.

[Rob Swain]

Looks better value than a lot I've seen.

If you are handy with a soldering iron and a few electronical bits then you can build one for less than a fiver including a box to put the gubbins in. The other advantage is you get to pick the lamp to put on the dash. Mine matches the starter and fuel pump warning lights (I know - but I used to keep leaving it on!).

Admittedly mine doesn't flash, though!

[Nick Allen]

If you are handy with a soldering iron and a few elctronical bits then you can build one for less than a fiver including a box to put the gubbins in.

Could you point me in a suitable direction to find out how to do this please, Rob?

[mikeblyth]

Good article for the mag, Iput a green light in just to remind me master was on. Would like
a flashing light perhaps with sound when engine off.

[Rob Swain]

Could you point me in a suitable direction to find out how to do this please, Rob?

It's been a while, but the circuit here:
http://www.aaroncake.net/circuits/lowvolt.asp
is the one I used, I think. Mine is definitely based around the LM339 voltage comparator in this diagram. I left the buzzer off mine, which is good as it is probably the most expensive component! Works fine without it!

I'll take a squint at my notes when I get a moment to check what I altered (if anything) to get it to work between 12 and 14.5 volts. You need it to trigger around 13.5 - 13.8 volts.

It works as an effective 'master switch left on' as well as 'my alternator / generator has stopped working' warning, without it being on all the time.

All the bits were available from Maplin when I built it!