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AB
4th October 2017, 07:25 PM
If you had a 12v device that came with an Anderson plug and you ran this device with an Anderson plug to alligator clip adapter to jumper leads 2m long to battery so clip to clip to a deep cycle battery would you get much of a voltage/current drop or is there just too many other variables to consider?

Aside from being a dodgy set up, lets pretend that each clip was clean and connected as best as possible, battery in great condition, etc as a general rule would you lose much current with that set up as opposed to a straight Anderson plug to battery source?

Winnie
4th October 2017, 07:53 PM
What is the device? For static use, like when your car is parked at camp it should be fine mate. Obviously not a good idea when you are driving.

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Sir Roofy
4th October 2017, 07:53 PM
IS this another 1 of your quick fixes ?
to many variables here

GQtdauto
4th October 2017, 08:48 PM
A lot of air compressors have long leads and alligator clips , anything I get now is converted to Anderson plug but depending on wire thickness and length of run there will be some voltage drop .

mudnut
4th October 2017, 08:49 PM
She'll be right. What could go wrong? Just use a bit of tape on the clips and leads so they don't short out.

AB
4th October 2017, 08:59 PM
Yep for static use only thanks Winnie. I know it will be fine was just curious of how much drop could you get with a set up like that, that's all.


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gubigfish
4th October 2017, 09:09 PM
Only one way to know for sure, set it up and get your multimeter and measure at all joins/connections to see

the evil twin
5th October 2017, 11:10 AM
Only one way to know for sure, set it up and get your multimeter and measure at all joins/connections to see

Wot 'e said ^^^

If all the connections are OK and the wire of the Anderson to Clip Adapter is of suitable gauge for the load I would expect less than 0.1 volt drop and negligible change to current flow at the connectors.
Replacing the battery clips with ring terminals or whatever to "permanently" connect the adapter to the Battery will have pretty much the same issues anyway.

Quick check of voltage with whatever it is you have connected running so the wiring is under load will soon tell you.

If the Bat +ve / Bat -ve voltage is the same or within 0.1 volt of the plug voltage at the pins of the last Anderson or the appliance plug (whichever you can get at from the back the easiest) then all is tickety boo.
If it is slightly worse than 0.1, say 0.2 or maybe even 0.3 lower at the appliance plug that will prob be OK if the load is pulling a fair few amps.

More than 0.2 volts drop under load solely across the 2 metre adapter and andersons would be an issue I would want to fix if it was mine

AB
5th October 2017, 11:54 AM
Thanks guys the load on start up is 10amp for 30 secs then back to 1 or 2. I'll check it out!


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Turtle_au
5th October 2017, 09:41 PM
Voltage drop is dependant on 2 things. The resistance of the circuit and the current you are drawing. If the 10 amp startup has a 1 volt drop, then the 1 amp load will only have 0.1 volt drop

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the evil twin
5th October 2017, 11:07 PM
Turtle is correct of course... so just to be absolutely clear now we know the max load current is only 10 amps...

If you are dropping more than .1 volts across the Adapter and Andersons at 10 amps you have issues.
If your voltmeter goes to two decimal places I would want it to be much less than that IE less than .05 volts

Trying not be confusing here but the difference is the way the voltmeter will round out if it only has 1 decimal place on the display
12.66 actual will display as 12.7 and 12.64 actual will display as 12.6 so the drop is actually only 0.02 but displays as 0.1

AB
6th October 2017, 05:58 AM
Thanks gents, yeah that was my concern with start up, I'll check it out...

bazzaboy
7th October 2017, 08:15 AM
At that distance you shouldn't have an issue. If the 12v device is one of the newer large portable air compressors, then cable the size of jumper leads would be required to cope with voltage loss and heat, as these compressors pull lots of amps. If this is your use, ensure you are also running the vehicle when used.

TimE
7th October 2017, 11:38 AM
Turtle is correct of course... so just to be absolutely clear now we know the max load current is only 10 amps...

If you are dropping more than .1 volts across the Adapter and Andersons at 10 amps you have issues.
If your voltmeter goes to two decimal places I would want it to be much less than that IE less than .05 volts

Trying not be confusing here but the difference is the way the voltmeter will round out if it only has 1 decimal place on the display
12.66 actual will display as 12.7 and 12.64 actual will display as 12.6 so the drop is actually only 0.02 but displays as 0.1

Just went and checked my extension lead, Anderson one end clips the other, and yes there is a 0.01v drop over its 3m length. Use it as an extension lead for my solar panel when needed.