Chargery - did i miss something?

[grizzzman]

I found the answer in another thread so posting the link here as well.

Chargery BMS now with Low Temp Cutoff

Are you sure about that? I have mine connected only through the balance cables and it turns on. I haven't checked if it has enough juice to power the relais though I think it means that it will not be enough to power relays fully not the BMS in general. I was looking at a possible DIY battery...

diysolarforum.com

Jason at Chargery said it will work for a 4S battery down to 11V. So I guess if LVC is set to 2.8V or higher it could work but there would not be much margin. Probably safer at 2.9V.

I run mine at 2.8 with no issues.

 

[mkaye]

I have been running a BMS8T since last fall off of the pack voltage. so yes you can. You just need to keep the amps pulled off "both" relays below 2.5 amps. A minor change using Micro Mini relay's and you can run relays in excess of the amp limit. I run TE contactors, they pull 3.8 amps (max) for about 20ms then drop to .13 each, the Micro Mini relays pull .08 amps. The contactors are powered directly off the pack, The Micros take the BMS signal and activate the contactors.

were you not able to run the TE relays off the pack?
waiting for my relays to arrive, but i was hoping they would work w/o adding 2 smaller relays
i did know they drew 3.8a for the short burst

 

[grizzzman]

I could run one without issue but not two. It would cause the BMS to reboot. So now I have one micro mini relay. I'm planning on using two. The idea is to take "all" the load off the BMS for longer life.

 

[mkaye]

got my relays and yes it reboots trying to power both relays
what did you use for a mini-relay in between?
i was going to look for a small SSR

 

[mkaye]

looking at this as my 1st choice

https://images-na.ssl-images-amazon.com/images/I/91PlLWnPvlL.pdf

100ma
asked Jason if black leads to relays are connected to a common ground as this would tie them together

2nd choice

Amazon.ca

150ma each so 300ma for 2

 

[grizzzman]

got my relays and yes it reboots trying to power both relays
what did you use for a mini-relay in between?
i was going to look for a small SSR

Use a micro mini. https://www.amazon.com/dp/B07VXDXLP...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

 

[grizzzman]

After looking at your first choice is a bit less in power but... More parts more likely a failure. On the pos. side. Easy peasy. Good luck with your project.

 

[mkaye]

yes, i was thinking about that - i would have to find a place to mount the circuit board
i think i'll go with option #2

the mini relays are US$33 on amazon.com (w/shipping & import duties), CDN$135 on amazon.ca!!

my 2nd choice is CDN$14

 

[Bob B]

I would pick a relay with an LED indicator. It is really nice to have that visual indication.

 

[aleks2a]

moving discussion to another topic.

Experiences or opinions on the Chargery BMS?

@MondeoMan Whether we fully agree or not this is a very interesting concept. I just wish it was in its own thread. Do you think you could sum up your thoughts and hypothesis then put them in its own thread in the battery section.. Since this really has nothing to do with the Chargery and I...

diysolarforum.com

 

[Bob B]

It's pretty hard to tell what he has going on from the information he gave. I would do some actual DVM readings on the cells to see what the voltages are reading compared to the Chargery.
It's kinda hard to blame the Chargery for the cells not being balanced when he is using a separate balancer.

I noticed he didn't take a temperature reading from the balancer. It is possible heat is being trapped up in that area.

Not to say he doesn't have a problem if the cell voltages are changing quite a bit per scan, but we don't know what the balancer is doing. If he is cycling his SCC, seems like he needs to have a little more hysteresis in the setting for HVD.

 

[Craig]

His SCC should not be cycling that fast he also needs to add some time before the unit resets from an over voltage event. Guess only a few of us have no real problems like this.,

 

[Craig]

Just had a thought put a clamp meter over each of the leads and see if there is energy passing through any ones more than the others.