Portable solar panel voltage drop

I am looking to purchase a 160w portable solar panel with a 10 metre cord not the usual 5 metre will the extra length drop the voltage causing the battery charging issues?. If so should or could I run longer cable from the back of the pv on both sides of the panels then put the regulator/ charger up near where I connect to the battery hopefully having the correct charge supplied. Thanks in advance any more tips or info would be great.
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Reply By: Racey - Saturday, Mar 07, 2015 at 09:22

Saturday, Mar 07, 2015 at 09:22
Steve, Always best to have the regulator close to the battery. Many of the MPPT regulators will permit a higher PV voltage to the regulator to charge a 12 volt system. Therefore you could connect the 2 panels in series, I.E. 24 volt nominal, and run that to the regulator and minimise the effects of voltage drop.

AnswerID: 549547

Follow Up By: noggins - Saturday, Mar 07, 2015 at 12:57

Saturday, Mar 07, 2015 at 12:57
Slight miscalculation there matey . Most panels I've used have a max voltage around 20 V ( Open circuit ) with a usual input to the reg at about 19V,
So using rubbery figures that would give the MPPT reg a total of around 40V input doing it your way
I'm not too sure many would handle that high an input.

FollowupID: 834948

Follow Up By: Racey - Saturday, Mar 07, 2015 at 17:35

Saturday, Mar 07, 2015 at 17:35
Hi Noggins, yes I am aware of the open circuit voltages involved. As I said there are many units suitable for this application. The easiest way of illustrating this is to do a quick run through the units list on Ebay.
MPPT solar controllers

Ones which come to mind are Tracer, PowerTech, and Voltronic, MPP Solar, just to name a few. Rated PV MAX voltage between of 50 volts to 140 volts.

FollowupID: 834966

Follow Up By: oldtrack123 - Saturday, Mar 07, 2015 at 17:48

Saturday, Mar 07, 2015 at 17:48
Hi Steve
It is ALWAYS best to have the regulator as close as PRACTICAL to the battery/s
even then you should miimise voltage drop by having cables suitable for the Amps & length
For 10M with 10A
9B&S will give 0.25V drop over that distance.

FollowupID: 834968

Follow Up By: oldtrack123 - Saturday, Mar 07, 2015 at 17:55

Saturday, Mar 07, 2015 at 17:55
Hi Steve
one otherv point that is a trap with some ebay sellers
They sell low voltage panels claiming they are suitable for charging 12V batterries
Ensure any panels you buy have20<22V open circuit
ie xxxW @ 17 to 18V

FollowupID: 834969

Follow Up By: oldtrack123 - Saturday, Mar 07, 2015 at 18:01

Saturday, Mar 07, 2015 at 18:01
Hi Steve
Nnothing wrong with Racey's idea either
Just make sure you get the 50V reg, as the open circuit voltage of some may be only 40V

FollowupID: 834970

Reply By: Member - Stephen L (Clare SA) - Saturday, Mar 07, 2015 at 13:32

Saturday, Mar 07, 2015 at 13:32
Hi Steve

Before you go and blow your hard learnt cash, please do your homework, as not all solar panel are what they claim as I recently found out.

I recently went through the exercise of getting a new solar panel a few weeks ago, and like most people, looked at ebay and think that you are going to get a great deal for just over $200.........how wrong can it be.

After some very good advise from a couple of members that know what they are talking about here on the forum, I ended up spending a lot more than I thought I would, on a quality 200w, high output solar panel from Kickass up in Queensland that offer first rate quality service, and you even get to speak to someone in person ( and it is even an Aussie and not an Asian Call Centre) , and not just waiting for return emails from ebay sellers. One great extra that I also purchased was their inline watt metre, that gives you a continual readout of the output of the solar panels, and the input to the battery you are charging, which will help you to maintain the highest output from my quality panel. Trust me this is just one case of you only get what you pay for. The quality is first rate and the type of cable used is about 3 times the quality and thickness as used on cheaper units on the market by the cheap ebay sellers.

A mate of mine recently purchased a 160w ebay panel from outbaxcamping, and trust me, it is the biggest heap, to think that companies can sell such cheap junk. Look at the image below of just how poor the quality was when it arrived at his place.....panel out of square, cheap hinges broken, and the regulator faulty. He is now going through the long winded saga of trying to get his money back.......well after a month of receiving it and countless emails to people that will not supply a contact phone number. Even after suppling then with a number of images of the poor quality of their product and a good number of email, he did get a reply saying they needed to inspect the unit first before they could swap it over, even though the images speak for themselves.

We have set up the panels together to see how they compare and it is like chalk and cheese.

Do not get caught out, to show you how good their products are, have a look at this link. I am in no way associated with Kickass, but one very happy customer that he is glad that I took the advise offered here on the forum.

Quality Solar panels from Kickass

Its you money, but if you want a panel that is well worth the extra money and with figures to show just how good they are, then DO NOT BUY CHEAP.

All the best in your selection.

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AnswerID: 549552

Follow Up By: Zippo - Saturday, Mar 07, 2015 at 16:49

Saturday, Mar 07, 2015 at 16:49
Stephen, your mate must have forgotten the first rule of buying items on ebay: ALWAYS use Paypal. The supplier can argue all he likes about inspecting etc but you can get a full refund.

I had one dodgy product and went through this process. The Oz-based seller didn't want to send a replacement or do a refund. Paypal refunded all including shipping cost, and (not that it's worth anything as it doesn't function) the faulty item is still here. I gave the seller the option to have it returned at his expense, but he passed.
FollowupID: 834960

Follow Up By: Member - Stephen L (Clare SA) - Saturday, Mar 07, 2015 at 17:22

Saturday, Mar 07, 2015 at 17:22
Hi Zippo

Not sure how he paid, but there is more than pride at stake now, when he saw the quality and the side by side performance of the two panels. If you check out the video from Kickass, what they show is 110% correct, from the quality of the carry bag, strong stainless steel hinges and latches, through to the quality of the 20 amp regulator, give their panels the edge straight away. As they say, their panels ARE not made to a price but QUALITY with a full 5 year warranty on everything and 25 years on the solar panel.

From what we could judge, the quality of the cables alone must have a huge effect on the voltage drop in the cheaper panels, with sub standard, cheap light weight cable supplied, no thicker than the we get when wiring up a trailer or caravan, which is just not acceptable when you want the full benefit from the panel to the battery.

When you look into the cost of buying the correct heavy duty cable and 2 anderson plugs, this immediately adds at least $100 on top of your cheap so called ebay special and the cheap regulator supplied another $100 or more, which then puts the price at a par of the Kickass.


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Reply By: Troopyman - Sunday, Mar 08, 2015 at 12:28

Sunday, Mar 08, 2015 at 12:28
You only get what u pay for .
Checkout the thick cables with Anderson ends .
Morningstar keeper .
Stainless hardware .
A grade bp panels .
AnswerID: 549599

Reply By: Member - graeme W (WA) - Sunday, Mar 08, 2015 at 15:04

Sunday, Mar 08, 2015 at 15:04
Hi Steve. There are plenty of ebay sellers out there with good quality panels for sale. I have purchased panels from smart-flash , marsol , bitdeals, and solar steve who used to be on this site. The panels have all met the specs as advertised by the sellers. The biggest hurdle for me was getting the right size or biggest panel to fit the space availible hence buying off different sellers. As others have said with the folding panels the closer the regulator to the battery the better. However just replacing the cable with 8b@s might be ok. Dont pay more than neccessary for 8b@s cable, i was recently quoted $300 for 30 metres of this cable from electical suppliers in my area but was able to source 50 metres (twin core) of 8b@s tycab australian made cable from ronado-pty-ltd off ebay delivered for $215. At that price it was worth buying the 50 metres for wiring my next 4x4 some time in the future.You have to email him for length prices over 25 metres. And they wonder why people are turning to ebay . Same for anderson plugs , good quality from a number of sellers for around $3 or $4 .
cheers Graeme.
AnswerID: 549614

Reply By: Member - graeme W (WA) - Wednesday, Mar 11, 2015 at 01:49

Wednesday, Mar 11, 2015 at 01:49
Hi Steve. Bit of free time so did a comparison on a bit deals 200watt folding with the kickass 200watt thats the topic of conversation here. The stats are nearly exactly the same , as is the cable although in both cases is only 6mm which in my view is to thin and should be at least 8b@s for that length , easy to rectify in both cases though. Frame and bag on a par and both have water proof regulators as most have anyway . Price of the bit deals $349 , the kickass $588. Lots of others out there as well just as good . The bit deals are rich solar panels.
Cheers graeme.
AnswerID: 549748

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