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Voltage Gauge- waste of time?
James - 10/1/06 at 10:48 PM

I was just thinking about (and cursing a little) undoing all the zip ties that hold my loom so as to fit the wires for the voltage gauge I've got.

Then I thought, what the hell's the point. I've been driving normal cars for 10 years now and so far not wanted for one. I've got a charge warning light, do I need a gauge at all?

Anyone found theirs particularly useful?

Cheers,
James

JoelP - 10/1/06 at 10:57 PM

saves you digging out a voltmeter when it wont start, i suppose Pretty useless apart from that.

ReMan - 10/1/06 at 11:00 PM

Nope, waste of time/money.

Dale - 10/1/06 at 11:44 PM

Does give a helpfull hint on altinator condition. And a warning if its overcharging as well.

02GF74 - 11/1/06 at 09:51 AM

quote:
Originally posted by James

Then I thought, what the hell's the point. I've been driving normal cars for 10 years now and so far not wanted for one. I've got a charge warning light, do I need a gauge at all?

Anyone found theirs particularly useful?



I have guages galore in my Land Rover, one of them is volt guage.


Also the speedo has alternator warning lamp.

To answer the second question, yes. The first alternator stopped charging but the lamp went off; I could see the volts were lower than they should have been plus there was a fuel/volts/water temp guage that showed the volts were down too.

As said, voltmeter is more precise tool to indicate alternator problems - you will also see if it overcharges - the lamp may come on iff excessive.

... but to be honest, in a locost it is excess weight and you if your battery fails, you are not likely to be stranded in an inaccessible position off road hence not so important. (annoying I have voltmeter one fitted in mine; I wouldn't have fitted it).

britishtrident - 11/1/06 at 10:49 AM

It gives you something to worry about ;-)


A useful diagnostic tool but not required if you have a DMM.

[Edited on 11/1/06 by britishtrident]

MikeR - 11/1/06 at 07:00 PM

DMM ?????????

gazza285 - 11/1/06 at 08:35 PM

Digital multi meter?

MikeR - 11/1/06 at 09:26 PM

Dastardly Mischievous Motor?

Dainty Mobile Monitor ?

NS Dev - 12/1/06 at 12:48 AM

Instruments are a waste of time!

Why do you need them! If the voltage goes low enough to cause a problem the charge warning light will come on! If the gauge drops a bit but not enough to be a problem what will you do....................................drive till the light comes on anyway cos your not sure!!!

Bin em, they just add weight!

Just use lights to tell you "good" or "bad"....simple!

In the workshop, you can connect gauges when you do maintainance, to check that everything is in order, but why carry them around on the car!

Browser - 12/1/06 at 09:30 AM

You'd probably find one of the many multi-function dash panels available would be able to be programmed so that if the voltage dropped below a preset limit it flashed a warning at you. Other than that, as stated above voltmeters are just extra weight.

MikeR - 12/1/06 at 06:46 PM

Ah, but if your voltmeter shows the alternator is over charging you could disconnect it and drive home before your battery gets fried. It could also show you the state of your battery when you know you have a problem so you've got an idea whats up.

Charge warning light comes on and voltmeter says you've got 12 volts - sounds like the fan belt to me. check, nip into womens lingerie shop and off you go ......

(yeah i'm trying to justify buying one)

02GF74 - 12/1/06 at 07:58 PM

quote:
Originally posted by MikeR

(yeah i'm trying to justify buying one)


no probs. an laternative, more accurate and chepaer is to use one of maplins DVM, the one they are selling 2 for £5 and canabilise it to show voltage - it can be done; I took one apart and altnough the rotary switch looks likea nightmeare, it should not be too difificultto figure.

I guess if a £20 voltameter saves a £40 battery then that is justification enough pluse it gives you somethig to do when stuck in traffic.

JoelP - 12/1/06 at 10:50 PM

it would be great if you could combine all the seperate gauges into one single gauge that just says ok in the middle, good at the top, bad at the bottom and maybe superb and dismal at the extremes

David Jenkins - 13/1/06 at 08:20 AM

You can get 'battery condition' tools that plug into the cigarette lighter socket - you could probably chop up one of them to get a 3-light indicator.

Otherwise you could easily make up an electronic circuit - LM3914 or 3915 comes to mind - that would show a row of LEDs.

It would be very easy to put 3 LEDs in a discrete corner of the dash.

David

NS Dev - 13/1/06 at 08:56 AM

quote:
Originally posted by MikeR
Ah, but if your voltmeter shows the alternator is over charging you could disconnect it and drive home before your battery gets fried. It could also show you the state of your battery when you know you have a problem so you've got an idea whats up.

Charge warning light comes on and voltmeter says you've got 12 volts - sounds like the fan belt to me. check, nip into womens lingerie shop and off you go ......

(yeah i'm trying to justify buying one)


When was the last time you cooked a battery with an overcharging alternator?

I have driven a fair few miles and never had it happen, and more to the point, I have driven tractors for over 10,000 hours and whilst I have had one fail, have never cooked a battery!

MikeR - 13/1/06 at 06:05 PM

which is just what i want to hear as my alternator is definately on its way to the big alternator factory in the sky!

(although i thought an overcharging alternator did cook the battery)

02GF74 - 13/1/06 at 07:37 PM

quote:
Originally posted by MikeR

(although i thought an overcharging alternator did cook the battery)


yes it does; you can smell it when it happens.

[Edited on 13/1/06 by 02GF74]

Marcus - 14/1/06 at 11:04 AM

Gauges, in general, are a bad idea!
Fitted an oil pressure gauge for the trip to France, couldn't take my eyes off it, making me paranoid

Marcus

DEAN C. - 14/1/06 at 08:23 PM

You're not paranoid ,its those people that are following you!

Seriously though I like to have an voltmeter so I have fitted one.

Being used to working in Plant and HGV workshops I find it a handy guide to knowing the state of the battery and I always use a Drop tester/voltmeter to crudely do a first diagnosis on starting/charging faults.
Also I tend to mentally note cranking volts as a matter of course.Yes I am that sad.

Then again if you dont really know what the readings mean dont bother.

I take the point about oil gauges though,I would not drive a track car without one but once you have had oil pressure problems you do fanatically keep watching the pressure.
Our Landy V8 racer often used to run with the oil light on after a couple of laps on a hot day,doesn't do much for your nerves when you're reaching over 100mph on forest tracks!

[Edited on 14/1/06 by DEAN C.]

Dale - 15/1/06 at 01:09 AM

Fuel pressure almost as important as oil on a boosted engine. Lose the pressure during hard boost and have some nice salvador dali pistons.
Dale