I’ve just fitted this voltmeter after I’ve found myself constantly waking up with no electricity.
Not only this, when I turn the engine on at night, to charge the battery, I’m never sure how long I should run it for to charge the battery up. I’ve been suspecting that I’m not really having a clue what or how my electricity is being used, when it’s such a valuable resource on the boat.
You need a simple instrument to tell you this.
It’s an inline voltmeter, and it cost about £40 from 12vPlanet, which sells all sorts of 12v accessories for caravans, boats and mobile homes.
In the picture, the engine is turned on, and the voltage is up to about 14v, which is right at the top of the scale.
I fitted this one myself by taking a line off the lighting loom, and running it to the meter.
There’s also a larger loom that the fridge runs on, but the cables are much thicker on that and the lower amperage serves. They’re coming from the same battery, and the voltage is the same.
I put this voltmeter in yesterday, and I’ve been shocked at what seems to be using the energy.
This is the reading at 4pm, after charging the battery till 11am.
As you can see, the voltage is around 12V.
And it stayed at this after charging my laptop up on the inverter until around 5pm. After that, it got dark.
This is what shocked me.
I thought it was the fridge running down all the power from the battery, but thanks to this device, I’ve discovered that it’s these.
Simple, old-school filament lightbulbs, basically eating up the electricity.
And they sure do eat it.
Look at the voltmeter after I put the lights on.
That’s the lowest setting, 10v.
This was taken at 18:46.
The amount of energy these tiny little bulbs must be pumping out must be amazing. And the evidence is all there.
12V energy saving bulbs
They’ve got to go.
I’ll be investing in some energy saving 12v bulbs very shortly.