Cheap Voltmetere

[minsted]

I want to fit a cheap voltmeter next to the switch panel-- such as this one from HK on eBay


http://www.ebay.co.uk/itm/Blue-Digi..._Measurement_Equipment_ET&hash=item19c15853f5


Do I need to wire it back to the battery or can I just wire it to a spare switch on the board.

Thanks

 

[VicS]

Id just wire it to a spare fused (and switched if you like) circuit on the panel.

If you do wire it direct to the battery be sure to fuse the circuit as close to the battery as possible

If you have two batteries you can use a double throw switch to read either battery

It will need suitable box to mount it in

 

[minsted]

Thanks
That's simple - I just have the one battery

 

[gjgm]

I want to fit a cheap voltmeter next to the switch panel-- such as this one from HK on eBay


http://www.ebay.co.uk/itm/Blue-Digi..._Measurement_Equipment_ET&hash=item19c15853f5


Do I need to wire it back to the battery or can I just wire it to a spare switch on the board.

Thanks

FYI, I bought one a couple of weeks ago for 99p +1.25 I think (same unit) Seems fine- the screen is quite bright. Took about 10-15 days to arrive from HK(though maybe dont order over Xmas and NYear).
I just tested it over a suspect voltmeter (proving it was suspect) and then just wired across a switch.

 

[JimC]

To be sure of getting a true reading you should wire the voltmeter direct to the battery via its own independent wire and a 100 ma fuse. If you connect it via your switch panel the reading will be affected by the voltage drop in the wire connecting the switch panel to the battery which could be significant when you have a lot of lights on etc. The voltmeter will itself draw some current, probably only a few milliamps but you won't want it on all the time. I would use a small push button switch of the 'push on - release off' type fitted beside the meter.

 

[ditchcrawler]

I bought mine from Sure Electronics on E bay.Seems to work fine.Mine was about 8 quid.I have it wired via the busbars so I can read either battery via my 1/2/both switch and it goes off when the batteries are off.It draws about 7 miliamps when on.A friend who is a marine electrician has three, one wired into each of his three separate battery banks.

 

[davidej]

To be sure of getting a true reading you should wire the voltmeter direct to the battery via its own independent wire and a 100 ma fuse. If you connect it via your switch panel the reading will be affected by the voltage drop in the wire connecting the switch panel to the battery which could be significant when you have a lot of lights on etc. The voltmeter will itself draw some current, probably only a few milliamps but you won't want it on all the time. I would use a small push button switch of the 'push on - release off' type fitted beside the meter.

+1

I fitted similar - they claim to be accurate to 2% so there is no point in allowing voltage loss in the wiring to give a false value

 

[VicS]

If wired to the panel it would give an accurate reading of the battery volts when there is little load on the system.

If the reading falls by very much when the system is loaded it could be a good indication that the wiring between the battery and the panel requires upgrading, or bad connections remaking.

 

[Egbod]

Volt meter

I fitted a similar voltmeter and just put it in the switch panel.
I bought a Red LED version sothat I could use it as a dim red light at night.
That is just as a moving around reference point light- not for reading

 

[William_H]

Digital voltmeters

I think you will find this meter really good. The current drain will be so small, basically the LEDs for lighting, that you can fit it anywhere in the system. Just be aware that it may be measuring volt drop if wiring is light.
The thing with these meters is to check the power supply arrangements. Older DVM chips needed a separate 9v battery supply however this one seems to be happy to run on supply being measured.
Why is it not available to Australia? Prejudice? I guess you can't blame them. olewill

 

[davidej]

If wired to the panel it would give an accurate reading of the battery volts when there is little load on the system.

True of course, but isn't the voltage under load a more useful indicator?

 

[davidej]

Why is it not available to Australia?

Can't you buy them on Ebay direct from China/Hong Kong like we do here?

 

[ostell]

Why is it not available to Australia?

And what has the Isle of White and Isle of Man done to upset them?