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[xsilvergs]

Still not sure about top balancing them as I'm sure they will not have a hard life.

Have you watched the YouTube vid's from Andy of "off grid garage" and his tests with different BMS, especially the Daly make that I think you have?

 

[Derekoak]

I watched Andy's video he does not like daly as they have a low maximum balancing current, however my basen cells are always close and small balancing currents occur frequently and seem to be enough. I top balanced my cells but they stayed close most of the time and the whole procedure took a lot of my time. Taking the cells to 3.65v does not do them any good. I have kept mine below 3.45v since then.

 

[xsilvergs]

I watched Andy's video he does not like daly as they have a low maximum balancing current, however my basen cells are always close and small balancing currents occur frequently and seem to be enough. I top balanced my cells but they stayed close most of the time and the whole procedure took a lot of my time. Taking the cells to 3.65v does not do them any good. I have kept mine below 3.45v since then.

For me it was interesting to see Andy's tests on different makes of BMS and how they differ in operation and balancing, probably blows a few people's theory's of how BMS's work.

 

[Derekoak]

I was a bit after the fact as I had already followed Phil and Harry and bought 2 daly bms, so watching Andy I could not change tack. Still daly bms are relatively cheap I think. So far my only objections are: I know no way to use the data within to automate relays. The SOC display is not highly accurate as I assume it is voltage based. Otherwise I am happy so far.

 

[SquirrellCook]

I was a bit after the fact as I had already followed Phil and Harry and bought 2 daly bms, so watching Andy I could not change tack. Still daly bms are relatively cheap I think. So far my only objections are: I know no way to use the data within to automate relays. The SOC display is not highly accurate as I assume it is voltage based. Otherwise I am happy so far.

Before I went down the victron resistive shunt method of coulomb counting I purchased a couple of inductive counters and if they would have worked they would have been good. One thing was the inaccuracy of the voltage displayed, but then if you think of it as a number that equals the actual volts it fine. So 7 displayed volts is actually 8 for example.

I have seen some Daly knock off BMS's for about half price. Also Daly active BMS's are appearing, but expensive at the moment.

I will use the Daly BMS to keep the Chinese happy, but charging will be controlled by the victron kit. Unless a better idea comes along.

 

[Sprinter 1 cup]

Nice again, 12v or 24 ?

 

[SquirrellCook]

24 volt again lol

 

[SquirrellCook]

Chatting with my owner, Anita. The suggestion was made to house the new batteries in the base of the wardrobe. This could speed up installation as the underside locker needs some reinforcement and repairs. They would still roughly be in the same place, but above the floor rather than below it. Another plus to this location is that it’s also warmer. Life is so much better when you can have a technical conversation with someone.

 

[wildebus]

sounds like a very wise plan.

 

[Nabsim]

I watched Andy's video he does not like daly as they have a low maximum balancing current, however my basen cells are always close and small balancing currents occur frequently and seem to be enough. I top balanced my cells but they stayed close most of the time and the whole procedure took a lot of my time. Taking the cells to 3.65v does not do them any good. I have kept mine below 3.45v since then.

Andy did an update on the Daly bms and was happy with how it worked

 

[Sprinter 1 cup]

Ill get a spat !
24v is a good save , got some 24v lighting out of ikea reject staion all leds, but no controller's. Not sure if they like 28v from batteries, or would they be be ok ?

 

[wildebus]

Ill get a spat !
24v is a good save , got some 24v lighting out of ikea reject staion all leds, but no controller's. Not sure if they like 28v from batteries, or would they be be ok ?

Generally IKEA domestic LED lighting doesn't like over-voltage. Hear a lot of people in the VW have failures after a while when they just cut off the 12av mains adapter and wire to the leisure battery and hit +14V.

 

[Derekoak]

Andy did an update on the Daly bms and was happy with how it worked

I have another small problem with my daly. It was cold about zero and my batteries read 3C. My low temp cut off was set at 5C so they showed a fault alarm, and charge mosfet off. As the batteries heated the charge mosfet did not switch on again until 9C. I messaged Harry and he did a quick test and his daly bms acted the same. There is a 5 degree hysteresis lag between switch off and on. Of course I guess if you are in a rush you can heat until the batteries show above 5C then temporarily reset the low temp cut off to 0C to get the charge mosfet on again then reset to 5C for safety the next time.

 

[Derekoak]

Chatting with my owner, Anita. The suggestion was made to house the new batteries in the base of the wardrobe. This could speed up installation as the underside locker needs some reinforcement and repairs. They would still roughly be in the same place, but above the floor rather than below it. Another plus to this location is that it’s also warmer. Life is so much better when you can have a technical conversation with someone.

That sounds very good. I have no space other than underslung for my batteries , but having experimental DIY stuff in difficult to access space is not ideal!!

 

[SquirrellCook]

I have another small problem with my daly. It was cold about zero and my batteries read 3C. My low temp cut off was set at 5C so they showed a fault alarm, and charge mosfet off. As the batteries heated the charge mosfet did not switch on again until 9C. I messaged Harry and he did a quick test and his daly bms acted the same. There is a 5 degree hysteresis lag between switch off and on. Of course I guess if you are in a rush you can heat until the batteries show above 5C then temporarily reset the low temp cut off to 0C to get the charge mosfet on again then reset to 5C for safety the next time.

Does the Daly BMS have an independent temperature sensor or does it have its own internal sensor?

 

[Derekoak]

My daly has a thermistor on a wire. Plugged in to a port

 

[wildebus]

I have seen some of Prowses videos showing although a BMS has a low-temp cutoff, it ignores the temp and doesn't disconnect. Don't recall whuch BMSes, but I think some Daly ones had that issue - so definately one to test out before relying on it.

 

[Derekoak]

You can limit the heater over run caused by the 5 C hysteresis, by siting the thermistor nearer the heater pad. For safety I placed it the other side of a cell from the heater, but I should move it.

 

[SquirrellCook]

Have you watched the YouTube vid's from Andy of "off grid garage" and his tests with different BMS, especially the Daly make that I think you have?

I had a look at a few of his videos this afternoon, but unsure about his conclusions about cell balancing.

 

[wildebus]

I had a look at a few of his videos this afternoon, but unsure about his conclusions about cell balancing.

TBH, I can't watch his videos all the way through. Jumps all over the place and too erratic.