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So, i take it, this means that the 17.1A is absorbed much quicker due to the higher potential difference (in set up 2) than the 18.38A can be absorbed in set up 1, despite being a higher Amperage. Thanks guys.

Divergence of greater than 20mv once above 3.43v/cell at a < 0.05cA rate(and increasing all the time thereafter). Going to be running some tests, so i might have a clearer picture in a few days. I just struck me odd, that at 3.65 top balance, i can't figure why they would diverge at 3.43v/cell...

Am i correct in saying, that version 4.0 of the BMS8T comes from the factory with the shunt pre calibrated, so no further calibration needed and also that no adjustments to the 'current calibration' tab in the munu necessary either? (so no need to set against a bench supply etc) Set up my...

I was watching the watts as i moved the current up and took it to 179W. I'll just add, that it was when i was doing it on my whole pack, not an individual cell. The secret seems to be, move it up slowly. I maybe got a little impatient.

Was looking at a 48V 300AH battery, which states that it is only 3840WH. By my calculations, i make it 14400WH....where am i going wrong? Also, it states that it is Lithium Ion, but then states further down in the spec that the chemistry is LiFePO4. They seem to use the wording interchangeable...

Ahh....thanks for that Jason. Would it be possible to run two shunts in series, the chargery connected to one shunt, then a victron connected to the other, in line next? The same power input/output would go through both shunts??

Thanks for all the replies folks. I have an electrician friend that insists i need an earth rod for the RCD to work.

Thanks Will, much appreciated. (y)

Looking at the comparison graphic below, i've heard several times that charging at a lower voltage threshold will take much longer to charge a battery bank. Can someone explain how this comes about, since the same 'overall wattage' is being input. Edit...cells would be 280Ah and 1C charge =...

In a motorhome setting with the vehicle insulated from 'true earth' by rubber tyres, does the RCD in a 240vac distrubution board still trip if either the live or neutral cables make contact with the van metal, when there is no true earth, only grounded to the vehicle chassis? On developing the...

Thanks steve, appreciated.

Thanks Hedges. (y)

Thats what i assumed previously, since the cells were getting trickled to maximise the time in getting them to a very close capacity, but my thinking seems to be wrong somewhere...just cant pinpoint where !!! Fafrd was right when he stated that balancing voltages was not quite the same as...

Thanks gnubie....had no intentions of spending that sort of money, but wondered how i was miss calculating. It is like 12.8v(4@3.2v) x 300ah = 3840WH instead of the expected 48v x300ah = 14.4KW You need to be quite the detective to work out what you are getting. At least at 4@3.2v cells...

@Craig @Ped Many thanks guys for your replies, much appreciated. So if one cell was slightly out of whack, so long as you didn't go to the extremes of charge/discharge limits, that cell wouldn't get any worse than where it started from? It might not over charge or over discharge, but my...

Thanks steve. My thinking was that no matter the parameter trigger, the whole battery bank gets shut down....everything safe first. Then the 100A(on second thoughts, this would need to be 200A) breaker could be turned off on the one pack that caused the trigger, then system powered back on, to...

Ok, excuse my ignorance, but is this not a case of cells being paralleled for balancing purposes, but will be used in series configurations in actual use? Thus the balancing takes on different meaning??? From the point of view of someone like myself, that wishes to do a belt and braces system...

Yes, that's what i was coming around to...a seperate 12v battery, gives me more capacity anyways and makes handling the small 12 dc loads so much simpler. (y) Just curious Ella, are you an electrician or just knowledge you have picked up along the way?

The recirculating shower is simply to use as little water as possible, but still have more the a two minute shower. The run off from the shower is passed through a basic canister sponge filter(each user has there own sponge & disinfected in milton between uses). A small pump simply pushes the...

Would siting the battery pack inside an old chest freezer with fans attached(ducted from outside the RV) be any use? Input and output fans could be activated at 25degC from the temp probe? Constant flow of cooler air over the top of all terminals....so long as you minimised the volume above the...

Wished i had an accurate meter. So my reading of the comments means there is no benefit to powering the unit externally when i have the 8S pack at 24v, since the difference in cell voltage will be negligible at that current. Anyone care to put a good meter across a 8S pack and report the cell...

Kudos....need more like you. (y)

The main thing about all your testing and fact finding on your particular cells, is that you get to know exactly when you must check on them due to discharge rate. You set a reminder on your phone or email system to go check and you know if you dont, you are risking 100's $$$ I'm still trying...

Joey, if you could indicate the wire sizing for the inverter to battery (say 600mm length) i'd be grateful. I was thinking of using 600A welding cable, but wasn't sure of the continuous use rating? I dont expect to draw anywhere near that current, but i'd rather spend a bit extra on wiring than...

@Boondock Saint Thanks for your reply boondock saint... I thought i had all the grounding worked out, but a qualified electrician friend has thrown a spanner in the works by insisting that i need an earth rod for RCD protection. As regards boats, if they have a metal hull, would this not...

Thanks for that filterguy. (y)

Fantastic mate. Great way of explaining things. (y)

Fire a message to Ghostwriter...she seems to have the most experience in this....can probably give you a definative answer.

IMS is simply Industrial methylated spirits...does a similar job to the acetone for cleaning all the dirt and grease off

The flange is 17mm dia. The cell terminal is approx 16mm, so i should be completely covered. Still waiting on them being made/delivered. Will post pictures once i have them set up. Edit... im hoping that by using braided busbars, that effectively the motorhome vibrations will be absorbed by the...