solar panel fitting

[graycat]

fitting solar panel

Hi folks, I have just got three 100watt solar panels and a mppt controller , my question is can I connect the controller to the main battery cable in the electrical cupboard as this cable is very thick and there would be less power loss using it, bearing in mind I have a sterling alternator to battery charger hooked up at the same point but I think the mppt should stop current flowing the wrong way, correct me if I am wrong, the other way is to take the lead from the mppt directly to the battery's.

[RobinJ]

I have just got three 100watt solar panels and a mppt controller , my question is can I connect the controller to the main battery cable in the electrical cupboard as this cable is very thick and there would be less power loss using it, bearing in mind I have a sterling alternator to battery charger hooked up at the same point but I think the mppt should stop current flowing the wrong way, correct me if I am wrong, the other way is to take the lead from the mppt directly to the battery's.

The controllers are designed to be connected direct to a battery, however there are other issues to consider.

In the event of a fault (assuming these will be running when the boat is unattended) a fuse should be fitted!

Provided they are fused there is no reson why they cannot be connected on the battery side of the isolator!

At peak output the current might be as high as 20A or more, so make sur ethe cable is thick enough.

 

So it will depend on the relevant location of battery connections/isolators and space for fuses!

[Ex- Member]

The controllers are designed to be connected direct to a battery, however there are other issues to consider.

In the event of a fault (assuming these will be running when the boat is unattended) a fuse should be fitted!

Provided they are fused there is no reson why they cannot be connected on the battery side of the isolator!

At peak output the current might be as high as 20A or more, so make sur ethe cable is thick enough.

 

So it will depend on the relevant location of battery connections/isolators and space for fuses!

 

Would it make sense to place the charge leads from the controller on the same battery connections as the alternator leads from the engine?

 

My bank will be wired the optimum method with same size leads from batteries connecting to a positive and negative post, then alternator charge leads will connect to those posts, should all charging leads go to those posts as well ie; solar & land chargers? or should they be connected the other side of battery isolator switch. I have a shunt fitted too.

 

Bit heath robinson at the mo, but this will all be rewired soon.

 

 

[Tony Brooks]

fitting solar panel

Hi folks, I have just got three 100watt solar panels and a mppt controller , my question is can I connect the controller to the main battery cable in the electrical cupboard as this cable is very thick and there would be less power loss using it, bearing in mind I have a sterling alternator to battery charger hooked up at the same point but I think the mppt should stop current flowing the wrong way, correct me if I am wrong, the other way is to take the lead from the mppt directly to the battery's.

 

 

The BSS requires most electrical equipment to be supplied via the master switch(s) so if you do as you suggest turning the master switch off should also isolate the solar panel so no charge.

 

You are allowed a solar panel, bilge pump, radio memory etc. to bypass the master switch as long as the cables are fused close to the batteries so doing it this way allows the panel to charge when you have your master switch turned off - like when you are away from the boat for a while. In theory you should also fuse close to the MPPT controller but if you have the correct cables I very much doubt the panels could cause a fire from a short to earth but the battery will - hence the fusing at the battery end.

[by'eck]

The BSS requires most electrical equipment to be supplied via the master switch(s) so if you do as you suggest turning the master switch off should also isolate the solar panel so no charge.

 

You are allowed a solar panel, bilge pump, radio memory etc. to bypass the master switch as long as the cables are fused close to the batteries so doing it this way allows the panel to charge when you have your master switch turned off - like when you are away from the boat for a while. In theory you should also fuse close to the MPPT controller but if you have the correct cables I very much doubt the panels could cause a fire from a short to earth but the battery will - hence the fusing at the battery end.

 

To that list you could add battery chargers, engine alternators and Combi charger/inverter. All of these should bypass the battery isolator to avoid damage should any of the devices be operated whilst battery isolator is open, unless you are disciplined enough to never make that mistake

[WotEver]

To that list you could add battery chargers, engine alternators and Combi charger/inverter.

Not according to the BSS, although most examiners would be hard pushed to tell if the alternator was hard wired or not.

 

Tony

[Ex- Member]

Started on my solar array today. Have joined the 2 panels which now gives me a good idea of total size. I was quite surprised how rigid the frames are on these panels.

 

The outside edges are 10mm box section of 2mm thick aluminium either side with a 6 mm cavity, I've bolted the 2 together with stainless steel button head allen bolts with 3mm neoprene seal between the panel sides making the join watertight.

 

 

Measures 1970mm x 1465mm

 

The timber frame has been cut ready to assemble, can't get on with it til Monday though, will post more then.

 

 

Edited April 19, 2012 by Julynian

[Grace and Favour]

Started on my solar array today. Have joined the 2 panels which now gives me a good idea of total size. I was quite surprised how rigid the frames are on these panels.

 

The outside edges are 10mm box section of 2mm thick aluminium either side with a 6 mm cavity, I've bolted the 2 together with stainless steel button head allen bolts with 3mm neoprene seal between the panel sides making the join watertight.

 

 

Measures 1970mm x 1465mm

 

The timber frame has been cut ready to assemble, can't get on with it til Monday though, will post more then.

 

 

 

Ooh! - they look solid - - -they're your Hyundi panels - yes?

 

 

Any would-be tea-leaf is going to have to be a strong boy to cart those off in an hurry

[Ex- Member]

Ooh! - they look solid - - -they're your Hyundai panels - yes?

 

 

Any would-be tea-leaf is going to have to be a strong boy to cart those off in an hurry

 

Hi Grace & Favour

 

They are indeed the Hyundai at 250 watts each. The main idea of joining them is to deter theft. Just as in the picture they're 38 kilos. by the time frame if fitted and the weight of brackets etc it'll be around 50 kilos so pretty difficult to walk off with

 

 

[Grace and Favour]

Hi Grace & Favour

 

They are indeed the Hyundai at 250 watts each. The main idea of joining them is to deter theft. Just as in the picture they're 38 kilos. by the time frame if fitted and the weight of brackets etc it'll be around 50 kilos so pretty difficult to walk off with

 

 

 

Aye - - there's now't wrong with making life difficult for the scrotes.

 

I must admit I've been closely following your thread - for I am just about to purchase some panels and know even less about the subject than you do I suspect

 

Though you've helped enormously - - inasmuch as I shall definitely buy an Outback FX80 MPPT - I know it's expensive - but hopefully it'll be the last one I ever have to buy (I'm a sucker for buying just once, but the best I possibly can)

 

I haven't decided which make of panels to get yet, though - but I know they'll be somewhere between 230w and 250w . . . .

 

I have to admit though that the more panel specs I look at - the more confused I become!

 

Oh what a wonderful world we live in!

[Ex- Member]

Aye - - there's now't wrong with making life difficult for the scrotes.

 

I must admit I've been closely following your thread - for I am just about to purchase some panels and know even less about the subject than you do I suspect

 

Though you've helped enormously - - inasmuch as I shall definitely buy an Outback FX80 MPPT - I know it's expensive - but hopefully it'll be the last one I ever have to buy (I'm a sucker for buying just once, but the best I possibly can)

 

I haven't decided which make of panels to get yet, though - but I know they'll be somewhere between 230w and 250w . . . .

 

I have to admit though that the more panel specs I look at - the more confused I become!

 

Oh what a wonderful world we live in!

 

Tis a tricky subject, to be honest most of the info I have gleaned has been from the forum. Smiley pete and chris pink have been especially helpful and others also.

 

I too favour the Outback still, although a few other models have been recommended and cheaper, but the 5 year guarantee does have genuine value. I'm not buying this until the last minuet as the price might come down. The cheapest I can find thus far is here.

http://shop.knowyour...k_flexmax_fm_80

 

If you use the Outback though I'm pretty sure that almost any single panel will work with it in the 200 to 300 watt range and you can even mix panel types I believe, so if you upgrade you can do with almost any panel or even wind charger.

 

Some useful info on this site too in the LEARNING ZONE area.

 

I'll post some more detailed photos of the frame building next week. all pretty much straightforward stuff using easily obtainable brackets and general fittings. The frame is only 93mm by 21mm thick treated decking board, but has a 15 year warranty against decay and insect attack. I'm pretty confident it'll be structurally sound, we'll see though. It also has a nice contemporary finish so will look good with a modern product.

 

http://www.timbercli...-metre-run.html

 

 

 

 

Edited April 19, 2012 by Julynian

[RobinJ]

If you use the Outback though I'm pretty sure that almost any single panel will work with it in the 200 to 300 watt range and you can even mix panel types I believe, so if you upgrade you can do with almost any panel or even wind charger

Most chargers have two channels at least.

I suspect you should not mix poly and mono panels on the same circuit, but I'm sure there is no problem with different wattages, provided they both have the same nominal voltage. With the built in protection you ought to be able to treat them like batteries (series/parallel).

[graycat]

Hi folks, I have connected the mppt to the main battery cable with a fuse in line after the isolator switch as I live on the boat the switch is on all the time, the three semi flexible 100 watt panels are supplying up to 33amps with full sunlight, but I will not know if this is the right reading until I fit the new amp meter, all in all its been three days now and the engine has not been needed even with all the cloud cover, my one regret is that I did not fit them from the start of living on board.

[Ex- Member]

Hi folks, I have connected the mppt to the main battery cable with a fuse in line after the isolator switch as I live on the boat the switch is on all the time, the three semi flexible 100 watt panels are supplying up to 33amps with full sunlight, but I will not know if this is the right reading until I fit the new amp meter, all in all its been three days now and the engine has not been needed even with all the cloud cover, my one regret is that I did not fit them from the start of living on board.

 

Hi Graycat, sounds good, especially if you're getting 33 amps as the max should be 25 amps for 300 watts. I was originally going to get the semi flexible but they were still a bit pricey for my liking so I've ended up with 500 watts of rigid solar panel 2 x 250 Would be interested to know what make yours are, should I ever expand my solar I might well go for some semi flexible for ease of application.

 

 

[Tony Brooks]

Not according to the BSS, although most examiners would be hard pushed to tell if the alternator was hard wired or not.

 

Tony

 

 

I agree, this was one of the things Gibbo kept banging on at the BSS about.

 

Ignoring the BSS I suppose the question is do you fuse the alternator lead near the battery so a short can not set fire to the cable/boat and risk the eventual fuse/holder failure damaging the alternator or do you not have a fuse and risk a fire.

 

Charging wise direct alternator connection is probably best but safety wise I am not so sure.

[Chris Pink]

Hi folks, I have connected the mppt to the main battery cable with a fuse in line after the isolator switch as I live on the boat the switch is on all the time, the three semi flexible 100 watt panels are supplying up to 33amps with full sunlight,

 

Which controller?

[Ex- Member]

With our 2 x 250 watt solar panels, should I run separate cables for each panel to the charge controller? so 4 cable lengths in total.

 

I note the cable rating in other listings is 20 amp, 500 watts of solar could produce 41 amps.

 

Or is it ok to parallel the panels at the array and run just 1 Poz and 1 Neg cable to the charger. The cable run would be 6 to 7 metres.

 

http://www.ebay.co.uk/itm/TWO-5m-MC4-solar-cable-one-pair-1F2M-1M2F-connector-connect-two-panels-/200653186764?pt=UK_Gadgets&hash=item2eb7dca6cc#ht_3581wt_922

[Chris Pink]

I thought they were high voltage panels?

 

Do they not have MC4 or MC3 connectors? You need y-couplers and a pair of tails to the controller?

 

eBay link; yes that's the one.

 

Your current calculation is wrong.

[Ex- Member]

I thought they were high voltage panels?

 

Do they not have MC4 or MC3 connectors? You need y-couplers and a pair of tails to the controller?

 

eBay link; yes that's the one.

 

Your current calculation is wrong.

 

Hi Chris

 

Full Spec for the panel here.

 

250Watt HiS-S250MG MonocrystallineHyundai Solar Panel Features

 

 

Dimensios 983 mm (W) × 1645 mm (L) × 35 mm (H)

 

Weight Approx. 19.0 kg

 

Solar cells 60 cells in series (6×10 matrix)

 

Output cables: 4 mm2 cables with polarized weatherproof connectors, IEC certified, Length 1.0 m

 

Junction box: IP65, weatherproof, IEC certified

 

Bypass diodes: 3 bypass diodes to prevent power decrease by partial shade

 

Construction Front : High transmission low-iron tempered glass, 3.2 mm

Encapsulant : EVA Back Sheet : Weatherproof film

 

Frame: Clear anodised aluminium alloy type 6063

 

250Watt HiS-S250MG Hyundai Solar Panel Technical Specifications

Nominal output (Pmpp) W 250

Voltage at Pmax (Vmpp) V 30.5

Current at Pmax (Impp) A 8.2

Open circuit voltage (Voc) V 37.5

Short circuit current (Isc) A 8.7

Module efficiency % 15.5

Temperature coefficient of Pmpp %/K -0.44

Temperature coefficient of Voc %/K -0.34

Temperature coefficient of Iscv %/K 0.052

I'll double check the connectors on the panel tomorrow. Just want to make sure the cabling is bullet proof so to speak.

 

Edited April 23, 2012 by Julynian

[Chris Pink]

So theoretical maximum current for 2 is 16.4A

 

It doesn't say whether they are MC3 or MC4 connectors. You'll need to check this.

[graycat]

Hi Chris, I took ages looking for a good mppt controller at the right price and ended up with a EPsolar 45amp Tracer-4215RN, its a well made unit and is giving very good results, at £200 it was well worth the cost, if you buy a cheaper unit be aware that there are a lot of substandard units out there.

[graycat]

Hi Graycat, sounds good, especially if you're getting 33 amps as the max should be 25 amps for 300 watts. I was originally going to get the semi flexible but they were still a bit pricey for my liking so I've ended up with 500 watts of rigid solar panel 2 x 250 Would be interested to know what make yours are, should I ever expand my solar I might well go for some semi flexible for ease of application.

 

Hi, I got them from ebay,the firm is "solar-energy 2008" and I found them very helpful.

[Chris Pink]

Hi Chris, I took ages looking for a good mppt controller at the right price and ended up with a EPsolar 45amp Tracer-4215RN, its a well made unit and is giving very good results, at £200 it was well worth the cost, if you buy a cheaper unit be aware that there are a lot of substandard units out there.

 

Interesting. Thanks. I thought those units worth a look.

[graycat]

Hi, I got them from ebay,the firm is "solar-energy 2008" and I found them very helpful.

I would get a good MPPT controller and that will make a big difference to the amount of power you get from the panels, the rating for the panels should be around 25amps but the controller is giving me more amps than that. the controller is a EPsolar 45amp.

[lewisericeric]

Julian - build the frame!! I cant wait to see pictures of it!