Solar regulator

goldcoaster · Senior Member

Solar regulator

wasn_me · Guru

If you have 500 watts of panels, that's capable of 41 amps in perfect conditions. You would need at least a 40 amp regulator. The 30 amp regulator would be dumping 10 amps. Waste of time fitting the extra panel.

If you upgrade the regulator go to an MPPT regulator. They're dearer but supposed to be around 30% more efficient.

Cheers Pete

goldcoaster · Senior Member

Thanks Pete , whats the formula to work the amps out.

wasn_me · Guru

goldcoaster wrote:
Thanks Pete , whats the formula to work the amps out.

Watts divided by volts = amps 500 divided by 12 = 41.6 amps

This raises a question. 12 volts is a nominal figure. Should the watts be divided by the regulated voltage, 14 volts ????? This would lower the amperage to around 35.

I hope some of the more knowledgeable reply to that question.

Cheers Pete

Jaahn · Guru

wasn_me wrote:
goldcoaster wrote:
Thanks Pete , whats the formula to work the amps out.
Watts divided by volts = amps 500 divided by 12 = 41.6 amps
This raises a question. 12 volts is a nominal figure. Should the watts be divided by the regulated voltage, 14 volts ????? This would lower the amperage to around 35.
I hope some of the more knowledgeable reply to that question.
Cheers Pete

Hi goldcoaster,

The best answer is to look at the back of the panels to see what their maximum amps are.

The connection between watts and amps and volts is a bit complicated for solar panels as the ratings given are designed to make them look better than they are really, not to be easily understood. furious

The maximum power is actually put out about 17 to 18 volts and at some amps quoted. If you multiply these two figures it comes to less than the rated watts. Yea it is a scam but everbody uses these figures to confuse the punters. confuse

A 12v 100watt nominal panel might put out about 5.5 to 5.7 amps. so 400 watts would be say 23 amps max. 500 watts would be say 29 amps max. The way to be sure is to look at the panels specs and check. Either on the back or from the supplier. Could be OK. hmm The problem with too many amps is the danger to the health and life of the solar regulator, not that it will dump any power.

Cheers jaahn

-- Edited by Jaahn on Wednesday 7th of January 2015 01:59:16 PM

-- Edited by Jaahn on Wednesday 7th of January 2015 02:02:02 PM

Peter_n_Margaret · Guru

wasn_me wrote:
If you have 500 watts of panels, that's capable of 41 amps in perfect conditions. You would need at least a 40 amp regulator. The 30 amp regulator would be dumping 10 amps. Waste of time fitting the extra panel.

This is sort of true, but you are unlikely to get 40 amps from 500W, or even close except on rare occasions.

Even if you did, the time you need the extra solar input is not when conditions are great, but when they are lousy.

So if the controller you have will handle the possible occasional overload without letting the smoke out, I would stay with it and just add the new panel.

Cheers,

Peter

oldtrack123 · Guru

Hi
Just to make it a little more confusing
MPPT regulator rating is based on their OUTPUT currentt.
To get an estimate of THAT
Divide panel Watts by battery voltage then take off 7.5%
A 40A MPPT reg should be just on it'd limit
With a simple PWM reg just divide the panel watts by 17
In both cases you may, in bright sun or clouds reflecting sun onto the panels get a higher current but it should not damage a good quality reg

PeterQ

wasn_me · Guru

I had a 120 watt BP solar panel on my previous van & regularly saw 8-9 amps. On my current van I've got 180 watt CNPV panel (same price as the BP panel) but rarely see it up to 9 amps. they were both running through a steca regulator.

I guess you get what you pay for.

Cheers Pete

PeterD · Guru

wasn_me wrote:
goldcoaster wrote:
Thanks Pete , whats the formula to work the amps out.
Watts divided by volts = amps 500 divided by 12 = 41.6 amps

I don't think so. 12 v solar panels develop their maximum power at around 17 V. So wee have 500 / 17 = 30 A (roughly.) When the controller drags the voltage down to 14 V you will get slightly more current. You also have to take into account that your panels will be down to 70 - 80% efficient due to their flat mounting

Totalrv · Member

Put a Pl60 Solar Regulator in and never worry about it again

goldcoaster · Senior Member

Thanks for all comments. Tell me more about the p160 regulator Total RV

-- Edited by goldcoaster on Saturday 10th of January 2015 07:36:36 AM

03_Troopy · Guru

Totalrv wrote:
Put a Pl60 Solar Regulator in and never worry about it again

More details mate, the only P160 I could find on Google is an orchard lopper..

Bill B · Guru

03_Troopy wrote:

Totalrv wrote:
Put a Pl60 Solar Regulator in and never worry about it again
More details mate, the only P160 I could find on Google is an orchard lopper..

Plasmatronics PL60 ?

Totalrv · Member

Plasmatronics PL60 is a 60amp solar controller

03_Troopy · Guru

At near $600.00, what kind of panel does it come with?

Jaahn · Guru

03_Troopy wrote:
At near $600.00, what kind of panel does it come with?

Yea hmm hmm confuse confuse

And not even MPPT either.

jaahn

Totalrv · Member

I just find the PL60 to be super reliable and handles large power input without any dramas and can be fitted with a shunt. Each to there own but,I'm sure eBay does some Chinese model for $10 that should be just as good......

03_Troopy · Guru

Do you sell them in your business Scott? I see you have solar systems listed on the bottom of you webpage.
For $600 plus, that reg is way overpriced for what you get. You can find equal or better quality systems at a fraction of that price.

Totalrv · Member

No I am not a seller of them,I install to customers budget,It doesn't bother me if someone spends $20 on a reg or $1000,I'm just saying they are really good quality

mr glassies · Guru

or a dingo trev i like em both
dibs

PeterD · Guru

mr glassies wrote:
or a dingo trev i like em both

I would recommend the Dingo in preference to the PL series. The PL series (together with the Steca and most of the cheap look alikes) are designed for positive earth systems. The Dingo series are designed for vehicular use where negative earth systems are encountered. The Dingo 20/20 is available for around $330 and the Dingo 40/40 for around $430. The prices may look a bit steep but remember the Dingos have built in monitoring that performs the same function of a quality monitor costing $2-300.

If you are going to get one of these style of controller I reckon you are mad to get the old PL series. With them you have to be careful what you earth in the system. If you earth the battery so you can charge from the tugs alternator then you can not earth the load part of the system. This means you must modify entertainment equipment so the aerial systems do not ground the equipment and possibly introduce interference. You have to be careful to make sure the gas or diesel heater does not get earthed. And so the list goes on. Yes there are work arounds for the positive earth systems, these have been done for years. Why not get the regulator designed for negative ground in the first place so you don't have to fiddle around with extra work.

03_Troopy · Guru

That sounds a lot better than $600 plus PeterD and more appropriate

SnowT · Guru

Totalrv wrote:
Put a Pl60 Solar Regulator in and never worry about it again

Sorry I'll stick with my little old dingo 20 to handle ALL of my Power needs.... NO matter what the Load is It does the job fine and it's Far cheaper than the PL 60....

Juergen

Peter_n_Margaret · Guru

I installed a PL60 in the OKA 10 years ago.
Top unit, as is the Dingo, made by the same Australian company. Local technical back up.

Cheers,
Peter