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Small Electrical Drain T3

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rbt1548 View Drop Down
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    Posted: 17 Apr 2018 at 21:41
 
I am working my way through things that need done, fixed and replaced on the T3, there seems a million things, too many to put in the "what did you do today " thread, once I've finished all the stuff, I may stick in a post.
I have a voltmeter that I was/am going to fit to the bike, so I opened the headlight shell to look for a suitable wire to attach it to, one that comes on with the ignition.
 
Whilst I was putting the probe of the multimeter  into the back of  the multi plug I noticed that without the ignition on one of the wires, a red, No. 4 in the block which feeds the PARK light, was giving a reading of 0.03V, just in case there was something wrong with the handlebar switch block I disconnected it from the headlight shell, same reading, 0.03V, I checked all connections pertaining to the particular wire, all the way back to fuse 4 that feeds the Park/rear light, they were all reading between 0.02-0.03V, however if I put a separate earth to a connection the voltage draw was 0V, after disconnecting and connecting various bits I thought it may be the ignition switch. With the switch OFF I connected the meter to the Red wire, the LIVE feed in from the battery, and to earth, 13+ volts, full power getting there, I then connected the meter between  the RED and the other 3 connection pins in turn, still with the switch OFF and each one was giving a reading approx 0.02-0.03V, so I thought there was maybe a small drain due to a continuity problem so tested the switch for continuity in the OFF position, NO continuity!!!
 
I cleaned out the switch, which had a fair amount of grease in it and retested it with the same results.
 
Why is it showing a drain from each switch spade connector in the OFF position, but no continuity between the LIVE feed in and the other spade terminals ?
 
 
  Now, I know a drain of 0.02-3 isn't massive, but it's a drain all the same, if anyone has an idea as to why it's draining I would be grateful if you could point me in the right direction, and should I be concerned about such a small drain?
 
 
Apologies for the long post but I thought I would put in  as much detail as I could.
 
Cheers

 

 

in

 

,

OFF

 

I

 

I

NO

.

.



Edited by rbt1548 - 17 Apr 2018 at 22:13
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iansoady View Drop Down
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Post Options Post Options   Thanks (1) Thanks(1)   Quote iansoady Quote  Post ReplyReply Direct Link To This Post Posted: 18 Apr 2018 at 10:22
13 volts is very high for a normal lead-acid battery. Are you sure it's not just a zero error?

You could check by putting the multimeter in ma range and connecting in series between the battery positive and its lead (obviously disconnecting first). But DON'T turn anything on.......
Ian
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rbt1548 Quote  Post ReplyReply Direct Link To This Post Posted: 18 Apr 2018 at 10:42
Originally posted by iansoady iansoady wrote:

13 volts is very high for a normal lead-acid battery. Are you sure it's not just a zero error?

You could check by putting the multimeter in ma range and connecting in series between the battery positive and its lead (obviously disconnecting first). But DON'T turn anything on.......
 
Thanks Ian, it's a moto batt gel battery, I might try and get hold of another meter in case mine is wonky.
 
I disconnected the charger lead this morning took a reading and left it about 2hrs and took another reading the difference was .3V. 
 
 Also strange thing is, I clipped my meter to the battery Pos terminal but hadn't connected the Neg and the meter read 0.01V ?????
 
I will give your suggestions a go and see how it goes.
 
What did you mean by 'a Zero error'?
 
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Post Options Post Options   Thanks (1) Thanks(1)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 18 Apr 2018 at 14:04
First of all, a multimeter showing 0.2V on a wire doesn't mean there is a drain. I suspect many would find such an anomaly if they were to check.
To see if there is an actual drain on the battery with the ignition switched off, you need to measure current in Amps (or low current in milliamps). If you have a DC amps range you can do this by removing the wire from the battery and connect the ammeter between the battery and wiring.

Odd readings on multimeters of a fraction of a volt can just come from your hands, Many cheap meters do this, don't worry about it.

With an analogue meter, where you have a pointer moving, the position of the needle at rest can be adjusted to true zero. With an uncalibrated cheap digital one it may be that zero is not exactly that.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rbt1548 Quote  Post ReplyReply Direct Link To This Post Posted: 18 Apr 2018 at 14:45
Originally posted by Brian UK Brian UK wrote:

First of all, a multimeter showing 0.2V on a wire doesn't mean there is a drain. I suspect many would find such an anomaly if they were to check.
To see if there is an actual drain on the battery with the ignition switched off, you need to measure current in Amps (or low current in milliamps). If you have a DC amps range you can do this by removing the wire from the battery and connect the ammeter between the battery and wiring.

Odd readings on multimeters of a fraction of a volt can just come from your hands, Many cheap meters do this, don't worry about it.

With an analogue meter, where you have a pointer moving, the position of the needle at rest can be adjusted to true zero. With an uncalibrated cheap digital one it may be that zero is not exactly that.
 
Thanks Brian,
Mine's a digital meter, while not cheap it certainly wasn't the most expensive out there, so I think it should be ok, as I said I'll try and get another one to try, but I think the conscientious, is 'don't worry about it' until it gives me problems. It will show zero and it may fluctuate a bit and show 0.01-0.02V.
 
I will do the tests suggested, probably tomorrow as I'm soldering my nipples just now!Shocked, cables, cables!!!!!!
 
Thanks again
 
 
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"I was so much older then; I'm younger than that now!"
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 18 Apr 2018 at 21:46
Just to be clear, he measured 0.02 and 0.03 (not 0.3 or 13 !!! )

These are in the hundredths of a Volt range. I'm assuming instrument is a DMM, if so it is not unusual for them to pick up stray electrical noise and show a small reading, especially as the input impedance on them is 1 Megohms so they can be quite sensitive. Just any bit of wire could potentially act as an aerial. This is especially true on AC millivolts range. My Fluke does this if I just plug the leads in.

HTH



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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 18 Apr 2018 at 22:52
Originally posted by rbt1548 rbt1548 wrote:

I will do the tests suggested, probably tomorrow as I'm soldering my nipples just now!Shocked,  
Masochist!.
Brian.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 19 Apr 2018 at 18:14


"Chicken nuggets don't dance on a Tuesday."
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rbt1548 Quote  Post ReplyReply Direct Link To This Post Posted: 19 Apr 2018 at 18:37
Originally posted by Brian UK Brian UK wrote:

Originally posted by rbt1548 rbt1548 wrote:

I will do the tests suggested, probably tomorrow as I'm soldering my nipples just now!Shocked,  
Masochist!.
 
Rubbish!, it's the best way to attach them Wink
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rbt1548 Quote  Post ReplyReply Direct Link To This Post Posted: 20 Apr 2018 at 08:33
Ok, chaps and chapesess, just an update on the alleged drain situation.
 
I did a parasitic draw test as suggested, I changed the battery on the meter first just in case it was running low, to be honest, I can't remember the last time I changed it and I've had the thing for years.
 
 I started off on the amps setting and then the milli amps setting, I got absolutely Zero, (no, not on the Kelvin scale, I wasn't on temp setting Tongue!!!!!), nothing, meter reading 0.00, so all does seem good, and on reading the advice given I seem to have been concerned about nothing. I also checked the battery two mornings in a row and even though I have been putting the lights on etc. and the voltage has dropped after doing this, the battery has been reading about 12.8-9V each time, so all seems good there.
 
Thank you all very much for helping out this electrical simpletonBeer, it might have seemed a daft and basic question, but it was something I wasn't sure about and thought it better to ask rather than risk something being wrong.
 
Cheers 
 
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"I was so much older then; I'm younger than that now!"
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 20 Apr 2018 at 11:04
As always, there is no such thing as a daft question, but we do get daft answers from time to time.
 
Checking for any parasitic drain is something all owners of the older bikes should do just to check all is in order. Later bikes with ECUs will always have some drain, gong back to my SPIII, the electric clock drained the battery over time.
Brian.

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