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Crazy phantom battery drain ?

Freddofrog. How is your meter working out ? Just read mine after an hour and it's showing 0.133ah. Can't understand it because dmm is only showing 24ma.
 
just got back in, I'll go and check now


edit:
0.417 Ah
4.5 Wh


Those pictures in #114 were taken 26 hours ago, but I might have disconnected it and started it again
The only thing that that meter doesn't display is accumulated time, so it's difficult to give a precise average Amps consumption.

But compared to your data, my numbers suggest that there is indeed another current drain in your car :(
 
I've edited the post above with the data


geoffdragon said:
Sorry can't post photos ?
Click to expand...
I'm ***uming that you haven't before, if not ......

you need a "photo-hosting" account, photobucket is usually used (not the only one)

You upload the pics into your photo-hosting account, get the url of the uploaded photo, then put it into the post. If you add "BB-code" to the url, the picture gets displayed

For example, the url of the meter on the battery is
http://i1103.photobucket.com/albums/g462/btg_pics/Accord/IMAG1041.jpg
(i1103.photobucket.com/albums/g462/btg_pics/Accord/IMAG1041.jpg without the http stuff so that you can see the full text)

if I put "[ img ]" in front of the url and "[ /img ]" at the end of the url (without spaces, I need spaces there so that the forum software displays the BB-code and doesn't get confused) then the forum software displays the picture

IMAG1041.jpg
 
geoffdragon said:
Freddofrog. How is your meter working out ? Just read mine after an hour and it's showing 0.133ah. Can't understand it because dmm is only showing 24ma.
Click to expand...
Maybe it took a few minutes for everything to shut down and it was using 0.2A+ in that time.
 
Way lower than mine. I'll have a look at how to post pics over the weekend. I have taken the bulb out of the boot light for overnight. Grasping at straws now. One thing I did come across is that a bad alternator diode can drain the battery even though the alternator charges ok. I'll see how the weather goes over the weekend and disconnect the feed cable to try. Maybe it's intermittent.
 
Cliffordski said:
Maybe it took a few minutes for everything to shut down and it was using 0.2A+ in that time.
Click to expand...
Well let's say it used 60A for 1 minute (!!!) .............. that is only 1 Ah to add on (because 1 minute is a sixtieth of an hour)
 
Cliffordski said:
I thought 1 Ah will only use 1A in an hour not 60A ? :wacko:
Click to expand...
1 Amp for 1 hour = 1 Amp-hour

60 Amps for 1 hour = 60 Amp-hours

60 Amps for 1 minute = 1 Amp-hour (it can't be the same as 60 Amps for 1 hour)


edit: if it's easier, do it as Watt-seconds, then convert to Joules, then convert Joules to Watt-hours
 
The meter indicates the number of cumulative amps used over any period of time you like. Then you can work it out from there
 
Cliffordski said:
So are you guys measuring A or Ah over 24 hours?
Click to expand...

geoffdragon said:
The meter indicates the number of cumulative amps used over any period of time you like. Then you can work it out from there
Click to expand...
To be more exact, it's sampling Volts and Amps very quickly and then calculating Wh and Ah at each sample, but we have to know the amount of time it's been connected to calculate average amps.

If you ***ume that the Amps have been constant, then the Ah reading will be proportional to time
 
geoffdragon said:
Freddofrog. How is your meter working out ? Just read mine after an hour and it's showing 0.133ah. Can't understand it because dmm is only showing 24ma.
Click to expand...
Do you mean 0.133A?
 
Cliffordski said:
Do you mean 0.133A?
Click to expand...
No he means 0.133 Ah (I know, sometimes he drops the "h" and writes "A" where he clearly means "Ah", but he doesn't write "Ah" where he should have written "A")

He is puzzled because he got 0.133 Ah with the meter connected for 1 hour, but at 24 mA on a DMM it should have thus given 24 mAh over 1 hour
 
Let's ***ume a device is using a constant 1 Amp for 2 days

That will give 48 Ah

But if the device used an additional 10 Amps for 1 hour during that time period, then a meter will show 58 Ah

The problem is then to find out when and why the 10 Amps was used (or maybe it was an additional 5 Amps for 2 hours)


edit: a couple of edits LOL
 
freddofrog said:
No he means 0.133 Ah (I know, sometimes he drops the "h" and writes "A" where he clearly means "Ah", but he doesn't write "Ah" where he should have written "A")

He is puzzled because he got 0.133 Ah with the meter connected for 1 hour, but at 24 mA on a DMM it should have thus given 24 mAh over 1 hour
Click to expand...
Note also that 1 hour is not a good sample, because any additional currents used for a few minutes will cause a bigger Ah reading, whereas over 24 hours that additional current for a few minutes will not show up as much

The point is, that if we ***ume that everything has settled down to 24 mA after a few minutes, and remains at 24 mA thereafter, then over 24 hours the meter should display close to 24 mA x 24 hours = 576 mAh
 
Well, I've tried a few more things.
Boot light disconnected for 15 hours - no difference. ( 133mah average)
Alternator disconnected for a hour - no difference. (166mah )
Fuse 20 out for an hour - no difference ( thought it may have been something to do with headlight adjusters ) (169mah )
I know these are short trial times thats why the readings are higher, but I would have thought if I had found the draw it would have shown a recognisable drop in consumption in an hour.
I wonder if a sticky relay could cause this drain.
If you remember, in an earlier post where the current dropped 124ma when I closed the boot. I think now that could have been the boot light going out, noot the micu.
Fast running out of ideas now. :wub:
 
freddofrog said:
Let's ***ume a device is using a constant 1 Amp for 2 days

That will give 48 Ah

But if the device used an additional 10 Amps for 1 hour during that time period, then a meter will show 58 Ah

The problem is then to find out when and why the 10 Amps was used (or maybe it was an additional 5 Amps for 2 hours)


edit: a couple of edits LOL
Click to expand...
Still confused sorry - please bear with the slow learners such as me - do amps measure amount/volume in the same way as gallons do with water?

If so then isn't an Ah the rate of flow not the volume that has flowed?
 
geoffdragon said:
Well, I've tried a few more things.
Boot light disconnected for 15 hours - no difference. ( 133mah average)
Alternator disconnected for a hour - no difference. (166mah )
Fuse 20 out for an hour - no difference ( thought it may have been something to do with headlight adjusters ) (169mah )
I know these are short trial times thats why the readings are higher, but I would have thought if I had found the draw it would have shown a recognisable drop in consumption in an hour.
I wonder if a sticky relay could cause this drain.
If you remember, in an earlier post where the current dropped 124ma when I closed the boot. I think now that could have been the boot light going out, noot the micu.
Fast running out of ideas now. :wub:
Click to expand...
As long as you are getting 20-30 mA after full shutdown and it starts okay when you want it to then that might be the best deal you're going to get!
 
Cliffordski said:
Still confused sorry - please bear with the slow learners such as me - do amps measure amount/volume in the same way as gallons do with water?

If so then isn't an Ah the rate of flow not the volume that has flowed?
Click to expand...

water is a good ****ogy for electricity

Amps = flow rate e.g. litres per hour
So Ah = litres per hour x hours = total litres (volume)


Cliffordski said:
As long as you are getting 20-30 mA after full shutdown and it starts okay when you want it to then that might be the best deal you're going to get!
Click to expand...
But over 24 hours he got 3.574 Ah
 
geoffdragon said:
Well, I've tried a few more things.
Boot light disconnected for 15 hours - no difference. ( 133mah average)
Alternator disconnected for a hour - no difference. (166mah )
Fuse 20 out for an hour - no difference ( thought it may have been something to do with headlight adjusters ) (169mah )
I know these are short trial times thats why the readings are higher, but I would have thought if I had found the draw it would have shown a recognisable drop in consumption in an hour.
I wonder if a sticky relay could cause this drain.
If you remember, in an earlier post where the current dropped 124ma when I closed the boot. I think now that could have been the boot light going out, noot the micu.
Fast running out of ideas now. :wub:
Click to expand...
Best thing to do is to extend the wires on the meter so that you can see it without opening the bonnet (such as dangling down under the car, maybe behind the nearside front wheel).

Then you can check it wihout disabling the alarm and opening the bonnet.

You then need to ...
1. reset it all
2. note the time
3. close the bonnet and set the alarm
4. write down all the meter readings
5. repeat 4 every hour for as long as you can
 
Cliffordski said:
He couldn't have if only 25mA per hour was flowing....one of those figures must be incorrect.
Click to expand...
but that's the point .....something else is coming on intermittently

using your water ****ogy, it's like seeing a trickle coming out e.g. 24 ml per hour but then after 24 hours you find the container has 3.574 litres :eek:

so somewhere the flow rate is increasing quite a lot for quite a long time
 
Cliffordski said:
He couldn't have if only 25mA per hour was flowing....one of those figures must be incorrect.
Click to expand...
btw .....no he isn't seeing 25mA per hour , he is seeing 25 mA, and then (after 24 hours) he sees 3.574 Ah

mA is mA, there is no such thing as mA per hour

mA = ml per hour of water, there is no such thing as ml per hour per hour

Ah is litres
 
That's right. If the draw on the dmm is truly 24ma. That should be in the region of 0.576 amps in 24 hrs. But it is 3.574 amps in 24 hrs so that 24 ma is a false reading for some reason.
 
So if the average is c150mA, and it is drawing c25mA a lot of the time, the culprit must be using a lot of juice when it does draw.
 
geoffdragon said:
That's right. If the draw on the dmm is truly 24ma. That should be in the region of 0.576 amps in 24 hrs. But it is 3.574 amps in 24 hrs so that 24 ma is a false reading for some reason.
Click to expand...
edited your sentence ....

That's right. If the draw on the dmm is truly 24ma. That should be in the region of 0.576 amps amp-hours in 24 hrs. But it is 3.574 amps amp-hours in 24 hrs so that 24 ma is a false reading for some reason

Now write it out again by hand 100 times you naughty boy !!! LOL
 
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