Fitting an ammeter and a voltmeter

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Owlsman
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Fitting an ammeter and a voltmeter

Post by Owlsman »

Hello everyone - I'm a newbie on here and indeed to 'moggie' ownership. I've only just bought a '62 Minor 1000 (positive earth, dynamo, no radio or other 'accessories' and no plans for any) and had it checked out professionally and got a 'thumbs up'....phew! Should have done that before I bought it, I suppose, eh?

I've had an oil pressure gauge and a water temperature gauge fitted which work fine but I want to also fit an ammeter and a voltmeter. I am aware that there are mixed views, on here and elsewhere, about the merits, or otherwise, of fitting them but I really do want to go ahead anyway....as I've bought 'em now! I'm working on the principle that you can't have too much info as to what is going on under the bonnet of a 56 year old car.

I know that the ammeter (in my case a +30 to -30 jobbie) needs to be very well insulated and have suitable wiring (I do have some rated @ 27.50 amp) but what I could do with please is an 'idiot's guide' as to how precisely to wire each of them up. ie: Is it the brown wire that is connected to the solenoid that I disconnect and then extend to one side of the a/m and then return from the other side of the a/m back to the solenoid where the brown wire was originally connected? Re the v/m, I know one side goes to earth......but where exactly should the other side be connected to? And do I simply reverse the connections if the gauge indicates a discharge - in other words, if fitted the wrong way round?

Apologies, in advance, if these seem pretty dumb questions which I'm sure must have been covered somewhere on here at some time but any pointers you could give me would be much appreciated please.

Many thanks.
ianmack
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Re: Fitting an ammeter and a voltmeter

Post by ianmack »

Hello and welcome to the forum. I’m a bit puzzled as to why you want both an ammeter and a voltmeter. Usually cars with dynamo charging systems have ammeters and cars with alternators have voltmeters.
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geoberni
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Re: Fitting an ammeter and a voltmeter

Post by geoberni »

Well 'Hello and welcome', ... it seems to me that you have a habit of getting the cart before the horse.
You told us that you brought the car before getting someone who knows anything to have a look at it, then you tell us you've already brought both Ammeter and Voltmeter.

You'll find plenty of info about fitting Ammeters and Voltmeters if you just search the forums....
I'm just surprised you haven't already been seeking a Flux Capacitor.....or have you... :wink:
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Owlsman
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Re: Fitting an ammeter and a voltmeter

Post by Owlsman »

Thanks for the prompt responses.

For the record, I did buy the car sort of ‘on trust’ as I was as convinced as I could be that both the vendor and the vehicle itself were pretty straight. The post purchase inspection was as much as reassurance for me as anything else and indeed, the report suggested that it was probably better than I thought!

Also, my ‘purchase’ of the ammeter and voltmeter did not involve any hard cash! They were actually acquired from a pal of mine for whom I did some gardening work, in exchange for these 2 instruments, which he bought for an MG he once owned, but never got round to fitting.

Anyway, back to the fitting. Regarding the ammeter I’ve either read or seen that it can be fitted by simply ‘extending’ the brown wire that is connected to the solenoid/starter to one side of the ammeter and returning it back to the s/s BUT I’ve also seen a wiring diagram that shows an a/m wired by taking a wire from one side of the ammeter to terminal ‘A’ of the Regulator Box. Are both methods acceptable and if so, which one is better or does it not make any difference?

Re the voltmeter – could someone please confirm it is correct to wire one side to earth and the other to ‘A1’ of the Regulator Box?

Thanks again.
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Re: Fitting an ammeter and a voltmeter

Post by JOWETTJAVELIN »

Hello yes, for the ammeter you need two hefty brown colour wires (generally twice the thickness of the other wires coming from the control box) to handle the current, which can be up to 20-odd amps, connect one to terminal A of control box pass through bulkhead to ammeter, the other brown wire needs to be attached from the ammeter to the battery cable side of the starter solenoid. Depending on the earth polarity of the vehicle (positive or negative battery earth) you may have to swap the connections on the back of the ammeter to give a correct reading, i.e. turn headlamps on with ignition off and the ammeter should show a discharge - if it shows a charge swap the ammeter connections.

The voltmeter ideally needs to be connected to the fusebox on a terminal only live when the ignition is switched on, to save it operating constantly and draining the battery. I think from memory this is terminal A2. Check the wiring diagram to be sure.

Disconnect the battery before doing any electrical work, especailly with ammeters.

Please bear in mind also, cars with 'uncut' dashboards without holes drilled for accessories are getting thin on the ground now and are more valuable, but if you do it under the dashboard so they are easily removable and put back to standard that is preferable.
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geoberni
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Re: Fitting an ammeter and a voltmeter

Post by geoberni »

Hi Owlsman
Well at least you didn't part with cash for them :D
Where are the Water Temp and Oil Pressure fitted?

I find myself wondering why you didn't fit all 4 gauges at the same time in a bank of 4, or perhaps that's what you are intending?

Personally, I've just got a Water Temp and an Ammeter, since I've got a dynamo still.
I'm not worried about Oil Pressure since I know the pressure switch works.

My ammeter was taken from the starter switch, since Basil is a SII with a Pull Start, not a modern fancy solenoid. :)

I'd say do whichever is easier and looks neater for your situation. I just got some black fabric electrical tape and made it all look respectable at a quick glance.

As I only have 2 additional gauges, and I was able to get an early RH Glovebox door quite cheaply at an autojumble, I was able to make up a panel to fit in the Drivers glovebox.
In the future, if needed, all can be removed without leaving a trace (other than the holes for the door hinges).
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Re: Fitting an ammeter and a voltmeter

Post by callyspoy »

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This is where i fitted mine. Not to everyones taste, but there were some additional switch holes in the dash for redundant switches, so i thought it better to fit the gauges in their positions. i prefer to reduce the amount of switches and gauges that are hanging.
Like yourself, i got this Oil gauge for free, as it was in the boot. Managed to buy a matching water gauge, so fitted them both there.
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Re: Fitting an ammeter and a voltmeter

Post by Owlsman »

Many thanks guys ('n gals?) ….....I don't want to run the risk of offending anyone! Seriously though, the prompt help and advice I've received is really very much appreciated. I've got some wire/cable rated at 27.5 amp which is quite thick (bit like me really) so I'm thinking I can use that for the ammeter. Should be Ok, eh?

The 2 dials for the oil pressure and water temp have been fitted to a 2 x gauge pod to the right of the steering column, screwed to the 'lip' on the underside of the dashboard. The 2 new gauges will be fitted to a matching pod (costing about 3 English pounds!) to the left of the steering column. If ever required in the future, everything could be removed, virtually without trace, save for a few screw holes.

I'm having a bash at attaching a couple of photos but not really sure how to do it, so anything (or nothing) could happen.

Thanks again to all concerned.

Alan
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oliver90owner
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Re: Fitting an ammeter and a voltmeter

Post by oliver90owner »

What is the alternator rated at? Do make sure the wiring will be rated accordingly.
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Re: Fitting an ammeter and a voltmeter

Post by Owlsman »

It's still a dynamo and I've no plans to convert to an alternator.
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Re: Fitting an ammeter and a voltmeter

Post by Nickol »

It is consoling to see others have the same set up as me - although the other way around. i.e. oil pressure and temperature.
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Gott schütze mich vorm Sturm und Wind und Autos, die aus England sind.
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Re: Fitting an ammeter and a voltmeter

Post by Owlsman »

Danke! Sie haben ein nettes Auto aber das Lenkrad befindet sich an der falschen Seite…..Ha,Ha! (Ich versuche Deutsch zu lernen und zu jede Gelegenheit es zu üben.)

For those not fluent in German, just like me.....''Thanks. You have a nice car but the steering wheel's on the wrong side! (I am trying to learn German and take every opportunity to practice it).
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Re: Fitting an ammeter and a voltmeter

Post by Nickol »

Perfekt! :D
Gott schütze mich vorm Sturm und Wind und Autos, die aus England sind.
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les
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Re: Fitting an ammeter and a voltmeter

Post by les »

I understood the Danke bit :D I've got an oil warning light and charging light ! In a standard car I think the beauty of a Minor is not having anything else to worry about. A personal view point of course! :D

Shropshiremoggie
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Re: Fitting an ammeter and a voltmeter

Post by Shropshiremoggie »

Tend to agree , also something else to go wrong !
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Re: Fitting an ammeter and a voltmeter

Post by myoldjalopy »

True! :lol:
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