Solarexploits

Cable, 100m & 4mm normal solar cable

Morning Gents, as per title, where are people buying from? I've not found anyone cheaper than CEF for cable, anyone else found anything cheaper & still decent quality Tradesparky seems very competitive on inverters, tho' their after sales, supply times etc. seem a bit iffy, looking at past reviews. they are also pretty competitive on poanels, JA solar are coming out at decent prices, but they do have a £125 delivery charge on anything under 50 panels, which makes it a bit less inviting. ABsolar seem very good on bulk orders & large panels. I'm looking for "besy bang for the buck" basically, rather than necessarily most efficient panel for size etc. Who have you found is godd for what? Thanks in advance for any info

@ConorDo you by any chance have a copy of the general instructions you could post? Not bothered about inverter instructions as obviously will come with whatever inverter he chooses,& he's intending to do his own panel mounts on a flat roof, it's more stuff like where AC & DC isolators should be located, labelling such as you've described above that sort of thing?

I have plenty of idea re the install, I've already installed my own off grid system & have an MCS array fitted 11 years ago. But I'm well aware that electrical regs change frequently & don't want to assist a friend installing something which is then knocked back by a sparky because it doesn't conform to latest guidelines. He's looked at buying a complete DIY kit, but can pick up the individual bits far cheaper elsewhere

Read the OP - he's not looking for an MCS system, he's intending to DIY,not concerned with selling back to the grid, for the extra cost of installation of MCS, you'd need to be selling LOADS back to the grid for about the next 20 years to justify the costs!

Surely the installation doesn't need to be done by them, simply a question of having a sparky sign it off surely?

Hope this hasn't been covered b4, but couldn't find it anywhere with search. I know some of the solar suppliers that offer DIY install packages issue a complete set of instructions which I thought would be handy, both as a "shopping list" & for guidance on exactly where to fit breakers/fuses/AC cut off etc. Just wondered if anyone that's purchased one of these packages had a copy of the installation guidance, I've had a look around the web & can't find anything that's more than a basic list of "install the panels, install this, that & the other & connect to grid", I'm looking for something a bit more informative than that to help a friend with a 3.6kW DIY g98 install, he's not bothered about getting paid for any return to the grid so doesn't need MCS Thanks for any help in advance

It's a Powland 4/5k, I'm told it's a Voltronic clone. I've had some replies on the diysolar.com forum which are suggesting bulk charge at 57.6 & float at 54.9/55, I thought I might go slightly under those voltages for safety's sake I now understand your point re the freshening charge, would it make sense to reduce the max amps setting to 20A which would be pretty close to their suggested 19A & should therefore prevent any damage

"What charger do you have and what are its capabilities ? " The charger is the inverter, so it's either charging from the PV array or, overnight for 4 hours, it's charging from the built in charger within the inverter, in both cases the only control I have is the voltage setting on the inverter, which it would appear is definitely set too low, as you're saying that 2.29Vpc would be OK as a charge voltage, (tho' wouldn't give a full charge) which equates to 55V across the 4,they are currently only getting 54V. There is also a current limit setting whivh I think I have at 30A max for both charge systems, I would have expected that to be fine with 170Ah of batteries, would get a 50% charge in around 3 hours I'm slightly mystified that it gives 2.4Vpc for both "freshening" & fast charge, but you're saying that would be too high? In my ignorance I'm thinking that I'm simply giving them a fast charge if I up the voltage2.4Vpc I must admit I got somewhat lost by the whole thing about measuring amps taken & recharging to 103% etc - unless you had a dedicated charger that you could both measure what's taken (or Watts taken!) & had complete control over what the charger puts in, that just doesn't seem a realistic proposition in the real world If I get several years of battery life I'd be happy with that as they would have easily paid for themselves & I would hope to replace with Li in a few years time, I'm not worried if I shorten battery life by, say, a year, what I don't want to do is either undercharge so they keep dropping below 50% (or I have to remove some load), or overcharge so I cook them, which in both cases would presumably shorten life significantly more! It would appear the batteries aren't ideal for charging from solar, but I did get them very cheaply, if I went for a voltage between the 2.29 & 2.4Vpc, say, 2.35, so 56.4V across the pack, is that going to get significantly more charge into them without being likely to do significant damage?

The batteries are 170Ah, if you look at the range nomenclature for Powersafe, a 190 is 190Ah etc I realise now, that a lot of the info is actually within the data sheet, including the resilience to deep discharge, I just wasn't understanding it fullyPowersafe Datasheet.pdfPowersafe Datasheet.pdfPowersafe Datasheet.pdf I think all I really need to be sure on now, is , am I reading the datasheet correctly, see attached below, am I correct that the charge voltage can safely be set to 57.6V (2.4Vpc) without overcharging?

"I use Wh counting and it is very revealing, even though I know I may be almost 1Wh out at any time." How is Wh counting done?

Thanks for that, I've put a post on there

I know from earlier testing the batteries have differing internal resistance, (are any 2 batteries actually identical???) hence the battery balancers, which usually keep things within 0.1V of each other, but surely you would still expect that if you add the individual battery voltages checked with multi meter (confirmed with separate meter) they would come to the same figure (perhaps within 0.1 or so) of what the inverter is recording 2.29Vpc would give an overall charge voltage of 55V, the inverter is currently set on it's standard AGM setting which is 54V, so would it be worth changing this to 55V as otherwise presumably I'm not actually getting a full charge in? Actually, having just reread the datasheet it says both freshening charge & fast charge should be 2.29 - 2.4Vpc, so does that mean in fact I should have the charging voltage set to 57.6? If that's the case then I'm not charging them fully in the first place. I obviously want to get a full charge in whenever available, but certainly don't want to "cook" them! I do measure load, but have no way of tracking total load taken, the load is inconsistent as freezer cuts in/out, TV, lights or computer switched on/off etc etc - I always wonder how folks manage to come up with any accyrate figure for their "base load" as mine is certainly far from consistent even overnight as freezer would still be intermittent

Had a good hunt round the forum as I thought this must have been covered b4, but if it has I didn't find it. There are a no. of charts around t'internet showing battery voltage as giving a good guide to state of charge of the batteries, but there appears to be some discrepancy/alternative figures when it comes to AGM & Gel batteries I have 4 x Powersafe 12V 170FS deep discharge batteries, which are described by Powersafe as valve regulated Lead acid - elsewhere in their literature they refer to them as AGM, looking at the charts at 50% discharge, which I would prefer to stay above, for sealed or flooded it gives 12.2V & AGM at 12.3V. The batteries have got battery balancers on them & are normally within .1 of a volt difference, possibly a spread of maybe 0.15 between highest & lowest Several questions I hope you guys can help with as can't find it given anywhere in Powersafe's spec 1. Is that discrepancy of 0.1V reasonably accurate, might seem a little petty, but given that a drop of just 0.2V takes them from being 50% to being 25%, that's quite significant 2. Whether you measure with a multimeter at each battery, or take the reading from the inverter input, unless all loads have been removed (which would include the inverter, so you wouldn't be reading anything from that!) then the voltage you record is going to be under load, rather than the unloaded volts given in the charts - how significant is this likely to be, my load when no solar charge available is typically around 3 to 5% according to the inverter? - no idea how accurate that figure is, nor where it calculates it from or how. There does seem to be a slight discrepancy between what the inverter displays & measuring with a multi meter, for instance inverter displays 54.0V (it has increments of 0.1V), individual battery readings are 13.35, 13.38. 13.43 & 13.46, so I would expect a reading of 53.6V at the inverter? 3. As soon as the batteries are no longer being charged with solar, the battery voltage seems to drop quite quickly into the 49 to 49.9V level, load would be around 300 - 400Watts at this period, over the next couple of hours load rises to around 600 - 700W for a couple of hours b4 dropping back to around 200 Watts, by this point, currently around 4 hours after the sun's gone down, battery voltage is down in the 48 - 48.9V area, If I'm wanting individual battery voltage of 12.2V as a min, this is marginal, if it should be 12.3, then it's already too low & even with just 200W, a 4A draw, by the time the charger kicks in, another 2 & 1/2 hours later, will have dropped further - I'm not around to monitor this as already asleep by that point! Am I letting battery voltage drop too low, bearing in mind these are "on load" volts? 4.Having been charged on the overnight cheap leccy for 4 hours, by around 7am, still drawing around 200W at this point, there is already some (very small) incoming solar & voltage is up to 49.5 - 50.5 range - does that sound sensible? 5. How resilient are deep discharge batteries to dropping below that 50% & are the voltages you see in the common charts accurate for this type of battery, or are they taken from typical car battery sizes & what I'm looking at I should expect to be different? These were SH batteries, but are dated 2021, I started using them earlier this year & unfortunately as I didn't understand balancing & had some other hiccups, I did have one or 2 of them down at below 11V a couple of times, when they arrived with me they were showing 13.0V off load, I'm wondering if I've done some damage, but the pack as a whole has worked so much better since having the balancers on. From the charts anything below 11.8V is completely discharged, however, as I accidentally discovered, this is most certainly not the actual case as i defo measured at least one unit below 11.0V & others not far above & inverter was still working fine & supplying power as normal, it's safety cut off voltage is far lower at 42V or 10.5V per battery??? Sorry for all the Q's, hoping someone can help!

Just a thought, would it not be cheaper to buy an off grid inverter & simply take part of the house off grid as a completely separate setup? This is what I've done using SH panels & batteries with a new inverter So far as I have been able to establish providing the circuits you take off grid are completely separate to your existing consumer unit etc. then there is no further application required, as, although generating, the generating side is not connected to the grid?

Thanks, your interpretation is similar to mine. Difficult to check as my cheap leccy is 12.30am to 4.30am & I'm usually asleep! However, cane home late on Saturday night/Sun morning & although in no fit state to check things out properly or accurately, the AC to the inverter was on & batteries were showing being charged by mains, which is the intention, saves voltages sinking too much overnight when no other input available They are AGM batteries, so have set the max charge figure (if we're right that that's what it is!) to 55

Bump! Oh dear 39 views & no response, does everyone else find it as confusing as I do .....

I recently installed a Powland 4/5kW off grid inverter which charges my batteries & supplies around half of the household circuits. It's been working brilliantly, but I'm struggling slightly with the descriptions of some operations. It has a built in 48V charger & I have set the AC supply on a time switch to charge the batteries overnight on the off peak tariff. In setting the actual voltage point up there is a setting, prog 12,described as "Setting voltage point back to utility source when selecting SBU priority or solar first in proghram01" & a separate setting, prog 13 "setting voltage point back to battery mode when selecting SBU priority or Solar first in program 01" I have SBU selected in prog 01 which is "Solar provides power to loads as fist priority, if insufficient, battery energy will supply power at same time. Utility provides power to the loads only when battery voltage drops to either low level warning or setting point in prog 12" There is no mention of the second setting prog 13 So, I want the cheap leccy to charge the batteries for 4 hours unless they are already pretty full, prog 12 offers settings from 44V up to 51V, so if I set to 51 then unless battery voltage is already above 51 (unlikely after around 6 hours or more of batteries being on load) then it should charge them? Have I got that right & will it cease charging when it hits 51V? Or, is that what prog 13 as described above does, which offers voltages from 48 up to 58, so, if I want it to charge until full then set for 58V? I'm sure it's all obvious to those used to this, I just find the wording confusing & want to make sure I have it right! Thanks in advance for any assistance!

I've had a Solic installed for around 10 months or so now. Simple installation, particularly if you have a spare MCB in the consumer unit. Cost was around £130, I believe it's already paid for itself or is very close to doing so, as we've had free hot water from April thro' to now & used zero gas during that period other than briefly to service the boiler. Up until April it was only assisting with the water heating, & I suspect we'll be back to that situation soon, but even in the winter months there was some limited diversion on sunny days

Just for info, I disconnected the neutral from the consumer unit, everything now works as it should - thanks for the assistance, sometimes just talking things thro' & thinking about them halps a lot - saved me time in guessing what was likley to be wrong 7 hot the nail on the head first time, just need a double pole switch now!

Sorry, I know they are neutrals, I'm more used to DC & think of everything as +ve & -ve. So to confirm that's the cause I just need to disconnect the connection from the consumer unit & retest?

I've attached a dreadful schematic below, unfortunately had no colours available to make it more obvious, must buy myself a new set of crayons! However in drawing it I think I may have answered my own Q. What I've not put onto the schematic as it was simply getting too crowded, is that the switch from Inverter to mains switches ONLY the live cable, the neutral & earth cables from the inverter to the main consumer unit are connected earth to earth, neutral to neutral at that point. Now, presumably I should be able to connect the 2 earths, as they are already connected at the inverter, but I'm guessing the problem is that the 2 negatives, one from main consumer unit & one from the inverter consumer unit need to be kept separate, in other words I need a double pole switch?

It seemed bizarre to me too - until I thought about how household wiring is connected, there are various different types of mains earth setups & I certainly don't understand them all, I'm not a sparky, but where my mains enters the house the main earth terminal is connected directly to the negative at the main fuses, that negative line is also tied to earth at various points along its length from the sub station to your home If I disconnect the battery then the inverter will be off, I'd need to recheck instructions, but IIRC it tells you to connect battery first b4 mains hookup, in hindsight I should have checked the system worked with mains b4 adding the switch that switches some outputs from inverter to mains - wonderful thing hindsight .......

Don't think you've understood the post. The 2nd image was for reference - that's not how my system is wired

So I've recently installed a new Powland off grid inverter. It has the ability to charge the 48V lead acid battery bank at 48v which i can set to use overnight on the off peak tariff. I've got it all basically setup - see pic & everything works fine, panels charge batteries, inverter works perfectly, but when I connect the inverter to the mains (not charging, just connect the supply in via a 3 pin plug) recognises the iinput to the inverter, but after just a few seconds throws the RCD out on the supply from the inverter to the house circuits. I already have suspicions as to where the fault lies, but am no expert when it comes to exactly how the RCD recognises a fault, hoping someone here with more knowledge can help If you look at the setup pic you will see high on the wall I have a switch which can switch feeds either from the inverter or from the mains to certain circuits, hence when batts are running low, or no sun, I can switch some of the drain off from the inverter. Within the switch the earth from the inverter & the household mains earth are connected. I'm intending to fiot an earth rod, but not yet done & at present rely on the incoming mains earth - I'm guessing the fault lies here, but what do I do to correct it? I have seen an image from a FB solar group - see second image - which suggests the neutral & earth from inverter should be connected (same way incoming mains neutral has direct connection to earth), is that likely to fix the issue, but if earth & neutral should be connected that way, why would that not already be done within the inverter? Any help suggestions much appreciated b4 I start disconnecting/connecting things until it's fixed - having the overnight charge facility would be a massive boost for the batteries