volt meter install

[retromadness123]

Hello guys just want to know the best way to install a volt meter, I don't really fancy splicing in to existing wire In the so was wondering if I could connect a switch to power it, would this be ok? And any ideas how-to install it, many thanks

[dodgerover]

Ebay special you can plug into the fag lighter?

[theheap]

Can't it be wired straight to the battery?

[ChasR]

Jan 28, 2017 19:08:04 GMT theheap said:

Can't it be wired straight to the battery?

The voltmeter would then be on all of the time and potentially be a drain on the battery. How much of a drain I do not know.

What car is it? Whenever I have done a voltmeter install I have either taken a spare feed off one of the ignition terminals on a BL car via the fusebox or done the same from the ignition wire from the car's Head unit (CD player, tape player etc.).

[retromadness123]

The car is a golf mk1, I was thinking, of using a 3 pin switch, so red wire from battery to + on switch, black wire from battery to - on switch along with the black wire of the volt meter and the other red and remote wire attach it to the ACC on switch, is this ok ? Also will a inline fuse be needed or would it be ok

[eternaloptimist]

Why don't you use a twinned spade connector on the back of a switched live (eg cigarette lighter) rather than badging in a switch? You don't need to splice wires. Have a search for vehicle wiring products' site - full of loads of good stuff on there

[ChasR]

I knew I was forgetting something! Fag light is where I took off the MGB one from. There I cut no wires but put a two terminal spade connector on, to go onto the factory loom.

If it were me I'd take off the ACC wire from the stereo ; there are not many old cars out there I have not seen without a botched loom for the ICE. Some HUs have an accessory take off in their harness as well which again negates cutting it.

It would also be safer. If you took a feed from the battery it would have to be fused right from the battery terminal itself for safety ; I've personally seen things become a "fuse" from the battery terminal to ground.

[Rich]

Jan 29, 2017 0:25:59 GMT retromadness123 said:

The car is a golf mk1, I was thinking, of using a 3 pin switch, so red wire from battery to + on switch, black wire from battery to - on switch along with the black wire of the volt meter and the other red and remote wire attach it to the ACC on switch, is this ok ? Also will a inline fuse be needed or would it be ok

That's not how you wire that switch. + is the 12V feed in (must be fused) ACC is what you are turning on with the switch (voltmeter + wire) and - should be grounded. It isn't a terminal for your accessory earth, it's so the bulb in the switch can light up when you turn it on.

[MiataMark]

I use a Digital voltmeter (with USB socket) that plugs into the cigarette lighter in the Discovery, after a couple of flat battery situations, cheap on eBay see below. You could also replace the lighter socket with a digital display, as below.

If you take the feed from the lighter or ACC then the reading will probably be less than the actual battery voltage. Careful about using a feed to other instruments as will probably have gone through a voltage regulator.

 
Engine not running - and running

These replace the lighter;


For my MX5 I got one of these that is push fit into where the accessory switches are.


But just found this (pricey at £17)

link

[retromadness123]

So to take a live of a cigrette lighter I put both the red/yellow (remote wire ) to the live of the cigrette and ground the black acc wire to the chassis of the car, or best bit just to get a cigrette lighter voltmeter no wires,

[MiataMark]

Jan 29, 2017 11:56:27 GMT retromadness123 said:

So to take a live of a cigrette lighter I put both the red/yellow (remote wire ) to the live of the cigrette and ground the black acc wire to the chassis of the car, or best bit just to get a cigrette lighter voltmeter no wires,

Yes, assuming the lighter is ignition controlled. For more accurate readings takes the sense wire (yellow?) back to the battery via a fuse.

This assumes the wires are, red 12v, yellow sense (monitored voltage), black ground/earth.

[retromadness123]

Thanks Mark, the lighter I have installed via battery with inline fuse so its always live, I do still have the existing wiring but they ain't the best hence why I put a new connection in, would you suggest it be best to just buy a 12v socket volt meter so it be easier plus the wiring for the cigarette lighter is directly on battery with a online fuse so maybe accurate? ?

[retromadness123]

Also what amp fuse would be ideal to use to wire the yellow wire to battery thanks

[ChasR]

Jan 29, 2017 10:42:20 GMT MiataMark said:

I use a Digital voltmeter (with USB socket) that plugs into the cigarette lighter in the Discovery, after a couple of flat battery situations, cheap on eBay see below. You could also replace the lighter socket with a digital display, as below.

If you take the feed from the lighter or ACC then the reading will probably be less than the actual battery voltage. Careful about using a feed to other instruments as will probably have gone through a voltage regulator.

 
Engine not running - and running

These replace the lighter;


For my MX5 I got one of these that is push fit into where the accessory switches are.


But just found this (pricey at £17)

link

I best not say what I paid for a Smiths item new! I did that as it seemed secondhand items went for not much less! It was for an MGB however and I wanted to keep it looking 'period' .

You've just reminded me. I need to get one of those Fag Lighter gauges .

[retromadness123]

Mmm gets met thinking with a cigarette one it be less hassle of wiring, and cutting plus can remove it easily lol choices choices, seen one on eBay for £3.18 So not bad price

[MiataMark]

Jan 29, 2017 14:05:06 GMT ChasR said:

I best not say what I paid for a Smiths item new! I did that as it seemed secondhand items went for not much less! It was for an MGB however and I wanted to keep it looking 'period' .

You've just reminded me. I need to get one of those Fag Lighter gauges .

Well you can go silly, this one is ~£170,



and for 99% of the time a simple digital gauge will do the job.

Mark

p.s. I've had the 'fag lighter' gauge for a year or so no issues.

[retromadness123]

Perfect thanks guys for all your advice appreciate it will order a socket one and see how it goes thanks again guys 👍

[Deleted]

Why do you need a volt meter, the only purpose they serve is another distraction to worry about?

[djefk]

Feb 2, 2017 12:56:09 GMT @1300dolly said:

Why do you need a volt meter, the only purpose they serve is another distraction to worry about?

Invaluable advice there which I'm sure the OP massively appreciates chap!

[Deleted]

Feb 2, 2017 13:18:10 GMT djefk said:

Feb 2, 2017 12:56:09 GMT @1300dolly said:

Why do you need a volt meter, the only purpose they serve is another distraction to worry about?

Invaluable advice there which I'm sure the OP massively appreciates chap!

It was a question, hence the '?'.
I am sorry I obviously have been mislead into thinking one could pose questions and give personal opinions on this forum.