Portable Solar Panel Regulator location Query ??

Hi to all ....
Need a bit of informed advice on regulator 'siting' for my folding solar panel.

My existing regulator was/is permanently fixed (adhesive'd) to the actual panel and has recently 'spat the dummy' (all indicator lights flickering constantly and only 'putting out' less than 8 volt) ..... after many years of good service.
Possibly my own negligence in leaving it exposed during a recent rainy period whilst charging a boat battery. The regulator was a relative 'cheapy' - but it did the job OK.

Have now purchased a replacement and see conflicting (to me) recommendations on whether to put this new regulator where the original one sits, (on the actual panel itself)
or, as many members alternately suggest, mount it close to the battery it will be charging ........

Had no troubles with the original sited on the panels themselves and note that almost all folding panel seem to have this same layout .

FYI : my normal cable is around 7 metres long, with Anderson plugs at each end but I occasionally use shorter lengths, for different functions.

So .... which is the 'best' way .... or does it not really matter ??
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Reply By: Member - John - Tuesday, Mar 24, 2015 at 06:09

Tuesday, Mar 24, 2015 at 06:09
Pedro, I am no expert, but all I have read and been told over the years is that the regulator needs to be as close as possible to the battery being charged. Also, did you purchase a MPPT regulator, as they optimise the panel output. Good luck.
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AnswerID: 551516

Reply By: Sand Man (SA) - Tuesday, Mar 24, 2015 at 07:39

Tuesday, Mar 24, 2015 at 07:39

Is your new regulator a stand-alone unit?

The best place for your regulator is as close to the battery as possible.
You can open up the junction box on your solar panels (the one where the cables from both panels terminate) and connect a new cable to this terminal point, thus bypassing the old regulator inside this junction box. You could even disconnect the original cable from its existing terminals and reconnect to the position mentioned above.

One thing you may wish to do is label the new cable output as "unregulated supply" so no one accidently connects it direct to a battery.

I have two cable outputs on my panels.
One, a regulated supply from the on-board regulator, which I can connect to the auxiliary battery in the back of my ute to charge it.
Another, an unregulated supply using a second circuit and used to connect to my van battery bank, which has a dc-dc charger with its own built-in solar regulator.


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AnswerID: 551517

Reply By: Member - mike g2 - Tuesday, Mar 24, 2015 at 12:22

Tuesday, Mar 24, 2015 at 12:22
Hi pedro, I also heard close to panel with good wiring and minimum overall cable distance to reduce resistance losses. mine from 4x4 show was stuck to rearside of panel.
looks like you've bought a new one, but.. I have a leftover spare , if you or anyone wants a FREEBY. sorry, cant guarantee it thou. ( CMP 12 , solar charge controller 12/24V 10A ) email me via contact member if interested.
AnswerID: 551531

Reply By: B1B2 - Tuesday, Mar 24, 2015 at 17:02

Tuesday, Mar 24, 2015 at 17:02
I have had a similar problem.
I replaced my old solar panel (it expired) and replaced it with a new one, and a PWM regulator. (Pulse Width Modulation). My old regulator was stuck under the panel on the roof rack.
The instructions say this Landstar PWM regulator will shut down over 85°, needed good air circulation, and was to be mounted vertically. Under the bonnet would be too hot for it. I will mount it on the roof rack under the panel as I use it while driving.
If you are only using yours when stationery you might be ok.


AnswerID: 551549

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