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Author Topic: Find positive on solar charger  (Read 2049 times)

guest23837

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Find positive on solar charger
« on: August 27, 2018, 10:20:38 PM »
Hi guys I got a solar trickle charger the idea being it will keep the generator battery topped up. the crocodile chips are missing and both wires are black, is there an easy (ish) way to find the positive wire. Many thanks

guest23837

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Re: Find positive on solar charger
« Reply #1 on: August 27, 2018, 11:40:20 PM »
Mercy Bucket Glort!

mike90045

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Re: Find positive on solar charger
« Reply #2 on: August 28, 2018, 03:45:34 AM »
Sometimes there is a slight "rib" molded into the cable insulation.  That helps the mfg, but I have no idea if they call it - or +

BruceM

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Re: Find positive on solar charger
« Reply #3 on: August 28, 2018, 05:37:50 AM »
+1 for Glort's suggestion.  A Volt-Ohm meter comes right after screwdriver, or was that before wire strippers?

BruceM

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Re: Find positive on solar charger
« Reply #4 on: August 28, 2018, 03:27:31 PM »
I use the cheap multimeters myself, though now I've had to spring for a bit more for true RMS meters.  Dropping things is unavoidable when you often can't feel much of anything with your fingers and frying meters in the Amps, oops, Volts game is also a specialty.  I only risk my good meters when I must and find the $7 meters of very good utility.

My workhorse is an old analog needle type Radio Shack meter I've had for 40 years. Piece of crap, terribly inaccurate, but does the job without the EMI of the digital ones which do me in after a while.  With a homemade active probe via op amp voltage follower, I can use it for troubleshooting my most sensitive low power analog circuits, where the load of normal meters affects the circuit too much.  The RS meter is totally fuse protected, and I still pop those regularly with the volts-oops-amps snafu.

If I ever get a windfall, I'd replace the Radio Shack meter with a Simpson analog.  Their meter movements are much better calibrated.








guest23837

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Re: Find positive on solar charger
« Reply #5 on: August 28, 2018, 11:11:30 PM »
My multimeter cost £7.00 off a well known auction site. I dont know why the battery is losing charge its almost new could there be something causing it to discharge on the generator when its switched off. here is the multimeter

BruceM

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Re: Find positive on solar charger
« Reply #6 on: August 29, 2018, 01:46:15 AM »
So hook it up and mark the positive lead with some red tape or something.


guest23837

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Re: Find positive on solar charger
« Reply #7 on: August 29, 2018, 08:26:16 AM »
My local spark said you need a Fluke multimeter costing about €400.00 which seems a lot for what I do with it. The rectifier on the generator produces almost 14 volts when its running which should keep the battery charged, it's a small car battery starting a single pot engine with no other loads on it. It would be useful for the missus if it were electric start and I wasn't around during a (rare) power outage. The little solar panel is making 18 volts in the rare sunlight here so I'm hoping it will keep the battery charged. It was in the boot of an old car I bought.

The Chinese really do make some things very cheaply I ordered these https://www.ebay.ie/itm/10PCS-Crocodile-Alligator-Clips-Connectors-for-Test-Leads-Red-and-Black-42-5mm/263719665526?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

guest23837

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Re: Find positive on solar charger
« Reply #8 on: August 29, 2018, 05:50:27 PM »
Thanks mate theres a few little jobs lined up for me this evening. There are little coils behind the flywheel making ac on the generator it goes into a little rectifier and 14v dc comes out. I already checked the battery all the plates are covered. These generators are started with a motorbike battery maybe its not producing enough power to charge a car battery?