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[Dave DND]

Connect an ammeter in series with the battery and measure the 'off' current.

You could buy a cheap multimeter (Maplin as a guess for under a tenner) with milliamps range.

The 'off' drain should be only in the order of 10 to 100 of milliamps - I doubt a clamp meter will be adequate to do that.

One area to check is the boot light - as prblem (IIRC) on Senators

Steve

Actually a clamp meter is the only way to perform this test correctly - virtually all of them will go down to very low sensitivities and wires can be checked very quickly without the need to remove or disconnect anything - cheapie multimeters will usually pop when wires are connected due to the small surge currents that exist before the current settles down to something worth monitoring.

Because clamp meters are that bit more expensive, you can see why autoelectricians with these correct tools often find the faults much faster than the diy mechanic with a Maplins meter.

 

[Andy H]

I can understand how an AC clamp meter works, it behaves like a transformer, A transformer requires AC to work though so DC clamp meters seem akin to alchemy to me 

Do they use the 'Hall Effect' I wonder?

Is this a suitable meter for measuring quiescent current in a car?

[Dave DND]

Perfect !!

You would struggle to find anything else that is of more use !!

 

[Entwood]

Very nice .. but at £65 a tad expensive as a "might be used" tool ..

[Dave DND]

Very nice .. but at £65 a tad expensive as a "might be used" tool ..

£65 DIY  Vs  Autoelectrician @ £40/Hour (at least 1/2 day)

Do the maths !!

 

[rustym95]

there is a member on e-bay selling somthing like that for £30, motorparts in nott's out of date stock.

[Entwood]

Very nice .. but at £65 a tad expensive as a "might be used" tool ..

£65 DIY  Vs  Autoelectrician @ £40/Hour (at least 1/2 day)

Do the maths !!

 

Agreed , and if I need one I'll buy it !!  But I think buying one "just-in-case" is a little OTT .. however the day my multimeter doesn't give me the answer ........   

[rustym95]

have you checked the alternator out put, if not would do that.

[Dave DND]

Very nice .. but at £65 a tad expensive as a "might be used" tool ..

£65 DIY  Vs  Autoelectrician @ £40/Hour (at least 1/2 day)

Do the maths !!

 

Agreed , and if I need one I'll buy it !!  But I think buying one "just-in-case" is a little OTT .. however the day my multimeter doesn't give me the answer ........   

Actually its an exceptionally usefull tool - and I would almost go as far as saying that its invaluable in a tool box - I use mine nearly as much as I do a multimeter, as not only can you see if you have a voltage, but you can see very quickly if the item you are checking is actually working by its current draw - much faster to diagnose with as you do not have to find a bare terminal to stick a probe on, simply hook around a wire and see.

 

[Kevin Wood]

Bear in mind before buying that the vast majority of clamp meters (especially almost all that fall below the price tag of the Sealey one mentioned) measure AC current only - because that's easy with a simple current transformer. They will obviously be useless for automotive diagnosis!

Read the small print and ensure it measures DC current using the clamp (some do have DC current measurement, but only by being introduced into the circuit in the sense that a normal "fiver from Maplins" multimeter does!).

Kevin

[Dave DND]

Bear in mind before buying that the vast majority of clamp meters (especially almost all that fall below the price tag of the Sealey one mentioned) measure AC current only - because that's easy with a simple current transformer. They will obviously be useless for automotive diagnosis!

Read the small print and ensure it measures DC current using the clamp (some do have DC current measurement, but only by being introduced into the circuit in the sense that a normal "fiver from Maplins" multimeter does!).

Kevin

Good point, but the cheaper ones that cannot measure DCA often have two banana plugs just to the right of the display -

This one shown looks fine, no extra sockets for probes and has DCA clearly marked on the selector switch

(That and we`ve also used this one before)

 

[Kevin Wood]

This one shown looks fine, no extra sockets for probes and has DCA clearly marked on the selector switch

(That and we`ve also used this one before)

 

Yep, agreed the Sealey one will be perfect. Just a warning for those who decide to shop around.

Kevin