.07 amp drain nothing switched on (1 Viewer)

Scout

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reading all "my battery is knackerd" posts lately,

I thought I'd just look at my battery drain rate, with no power on, 12 volt main switch off, radio off, alarm not on, Ive got a .07amp drain is this normal? my batterys are four years old if that amkes any differance?
 

cmcardle75

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reading all "my battery is knackerd" posts lately,

I thought I'd just look at my battery drain rate, with no power on, 12 volt main switch off, radio off, alarm not on, Ive got a .07amp drain is this normal? my batterys are four years old if that amkes any differance?

Depends how it is wired. Could be an alarm (will draw even if not set), or the panel itself. Could be a dodgy meter.
 
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Scout

Scout

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edit to o/p its 0.7 not .07amps

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hilldweller

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reading all "my battery is knackerd" posts lately,

I thought I'd just look at my battery drain rate

I guess this is the leisure battery/s ?

0.7A is a hell of a lot. If constant will destroy a battery in a week.

12 x .7 = 8 watts.

So what is eating 8 watts.

How did you measure this ? Did you remove one battery post or pull the battery fuse and slot in your meter ?
 

cmcardle75

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edit to o/p its 0.7 not .07amps

In any case, if you want to leave the battery for any length of time, you need either a solar panel or to disconnect the battery, as there's always something sneaking some current. I use a quick disconnect battery post on mine, although I've got solar as well.
 
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I guess this is the leisure battery/s ?

0.7A is a hell of a lot. If constant will destroy a battery in a week.

12 x .7 = 8 watts.

So what is eating 8 watts.

How did you measure this ? Did you remove one battery post or pull the battery fuse and slot in your meter ?

Measuring at the battery is best.
Pull the leisure battery fuse and see if you still have the discharge. If so its something wired to bypass your fuse box / control panel.
Otherwise put the leisure battery fuse back and pull all the other fuses. Replacing them one at a time should give the information required.

Good luck
Gordon

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Scout

Scout

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I guess this is the leisure battery/s ?

0.7A is a hell of a lot. If constant will destroy a battery in a week.

12 x .7 = 8 watts.

So what is eating 8 watts.

How did you measure this ? Did you remove one battery post or pull the battery fuse and slot in your meter ?

I just read it of off the pannel, turned of the main 12v switch, waited for the pannel light to go out, then read it, how would you read it off the battery?

take of one terminal and put the meter between post and coupling?
 
Nov 14, 2009
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normandy
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my scout is the same, but a .4 amp drain. never causes a problem because i have a couple of solar panels on the roof. i did hear something about the rear view camera causing the draw but never tested it myself. also my dashboard cd player is wired to the leisure batteries so it might be that as well? all the best sean

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steviebouy

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I'm pretty sure on our Dethleffs the auto frost drain on the heating circuit remains live when the 12v is off for obvious reasons. There is a way of shutting down more completely, I guess this is what Nirvanauk was alluding to.
 

TheBig1

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the suggestion of pulling the fuses for circuits from the battery, then putting back in one at a time and checking for the drain is the simplest way to isolate the problem. I was going to suggest it but someone else got there first:thumb:
 
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On my Scout it was the radio memory draining the battery.

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hilldweller

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how would you read it off the battery? take of one terminal and put the meter between post and coupling?

Yes as long as you are happy doing that and it's not going to wreck any settings in an alarm or radio.

There is another way, right next to our battery is the main protection fuse, I could pull that out ( same caution above applies ) and you can measure inside the fuse holder with a bit of fiddling, that means no spanner work.

That is the only way to get sure reading.
 

Jaws

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A few points

1) The alarm may not be armed but even quiescent it does draw something as its receiver is standing by waiting for the signal to turn on

2) Yep, some radios really draw a fair few milliamps on standby

3) But neither of those should be drawing over half an amp or even close

Can you clarify which battery(s) you are talking about .. Habitation or van ?
 
Nov 14, 2009
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normandy
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its my leisure batts that the draw is coming from. which way do you set the multimeter to test the draw? i can easily remove the fuse at the batteries and bridge this with my meter.
got me interested now! could it be that the panel isnt properly calibrated?

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cmcardle75

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its my leisure batts that the draw is coming from. which way do you set the multimeter to test the draw? i can easily remove the fuse at the batteries and bridge this with my meter.
got me interested now! could it be that the panel isnt properly calibrated?

Assuming you have a typical digital multimeter with a 10A DC range:

Remove the main fuse (having checked there is no other connection that bypasses it).
Have one lead in COM and the other in the 10A DC terminal.
Select 10A DC on the dial.
Touch both sides of the fuse holder.
If there is a big spark, withdraw quickly. If you do it quickly enough, you might save the multimeter.

Be very careful. In this range there is a dead short between the leads. If you touch 12V and an earth in this range, there will be a big spark, the leads will melt, the multimeter will explode and there may be a fire.
 

capinpugwash

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If this is the leisure battery it may be more than one thing.

I believe that the frost cut off/drain switch for the water heater constantly draws a small current, so this may be part of the problem as it draws it even though the 12v panel is off.
 
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Scout

Scout

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A few points

1) The alarm may not be armed but even quiescent it does draw something as its receiver is standing by waiting for the signal to turn on

2) Yep, some radios really draw a fair few milliamps on standby

3) But neither of those should be drawing over half an amp or even close

Can you clarify which battery(s) you are talking about .. Habitation or van ?


I think its the hab side l(2 X 85amphour) the van battery is only put into use when switched on, on the pannel. This swich is off so the drain is on the hab batteries?

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pappajohn

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if, after following CMCARDLES advise, the meter reads less than 2 amps then disconnect and switch to the 2amp range (if the meter has 2amp range) then reconnect.

This will show a more accurate reading to maybe a couple of decimal points.
 
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normandy
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ok , i went and did as you suggested with my digital multimeter and got a reading of 0.22 on the screen which i take is 220 milliamps? if so then that is a lot better than the 0.70 (700 milliamps) shown on the habitation control panel.

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hilldweller

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ok , i went and did as you suggested with my digital multimeter and got a reading of 0.22 on the screen which i take is 220 milliamps? if so then that is a lot better than the 0.70 (700 milliamps) shown on the habitation control panel.

Time to do some calibrations then. Make sure that the meter is on a suitable amps range and turn on some lights. Compare the extra reading on your meter to the screen. That way you can get an idea if the screen is lying or there are red herrings swimming around.

If your meter was 0.2 and the screen 0.7.
Add light.
Meter 1.2 Screen 1.7 that would say the meter is working but finding 0.5A somewhere.
 

pappajohn

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combination of dump valve, radio memory (if on hab battery) and alarm stand-by (if on hab battery), and the panel itself will draw power even when the battery switch is off.

that lot could add up to ,22amps.

if the radio is powered by the hab battery it will draw a considerable amount as the switched live wont be...it will be a permanent supply along with the memory supply (which should be live)

i replaced my old car radio and as there was no acc position on the key i wired both permanent (memory) and switched live to battery.....it pulled 190Mah....32amps per week
 
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Jaws

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Dunno about a good few MH's but those I have worked on have never had radio or alarm on the hab batts which is why I asked what batt was being drawn on..

I would be inclined to pull fuses until the draw goes to zero or at least very very low ..

Once you have found what circuit the draw is on it should be eas(ier ! ) to suss out what it is..

Even at a 220mA draw that is enough to flatten a pair of 85 aH batteries in about 20 days ( given a battery will be pretty well banjaxed much below 40% charge left )

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Nov 14, 2009
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normandy
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my dash cd /radio is wired so that i can switch it on without touching the ignition. i have pulled all the12v fuses on the sargeant and 4 that are in a holder under the bonnet and cant make the 0.4 draw stop. i disconnected the rearview camera as well and its still there. i think mine is the c d player in the dash and the fuse is behind it so i dont really want to start pulling that out. i did the "switch a light on" and measure with the meter and it corresponds exactly so i think the conrol panel meter is just not calibrated. i enjoyed that and learnt a little more, thanks all. sean

what shall we do now?
 
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normandy
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Dunno about a good few MH's but those I have worked on have never had radio or alarm on the hab batts which is why I asked what batt was being drawn on..

I would be inclined to pull fuses until the draw goes to zero or at least very very low ..

Once you have found what circuit the draw is on it should be eas(ier ! ) to suss out what it is..

Even at a 220mA draw that is enough to flatten a pair of 85 aH batteries in about 20 days ( given a battery will be pretty well banjaxed much below 40% charge left )

i was surprised when i found out mine was wired from the hab batteries but i have 210 watts of solar on the roof so even on the dullest day the draw wont affect my batteries
 
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Scout

Scout

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if, after following CMCARDLES advise, the meter reads less than 2 amps then disconnect and switch to the 2amp range (if the meter has 2amp range) then reconnect.

This will show a more accurate reading to maybe a couple of decimal points.

o/p here

Ive just gone to check the battery as discribed above, Ive got two batteries, I pulled fuse on the first one and it has melted and blown, I checked the ampage draw on the PANNEL it had changed to .4amp and th voltagwe had gone ujp to 12.6 (was 12.4 with blow fuse in ) I replaced the blown fuse with correct size, I checked the pannel again the ampage draw is now steady at .3amp (which seems to be in line with other scout owners).

I put the charger on whist I type this, what next pepole?

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