Large Server Rack fusing

[S Davis]

I worry about the Positive Busbar somehow shorting to the grounded case.

Yep, for me that would be 800amps to pop the four 200amp class T fuses in each battery.
It would not be pretty I am sure, I have seen HVAC techs vaporize wrenches with 480 three phase and imagine it would be about the same.

 

[chicagoandy]

Current Connected site clearly shows you want the Pytes if you want closed comms with solark as a supported configuration

There is no such claim for their Ruixu listing.

Sol-Ark will happily do closed-loop comms with anyone that supports the protocol. They advertise "Any Battery", and they list more than 20 supported battery vendors. https://www.sol-ark.com/battery-partners/

And in this case, I do have an installer that is more than happy to support.

That said, I removed the previous post.

 

[chicagoandy]

Hang on. Are you claiming that you told Current Connected you needed batteries with communications with a solark and they recommended ruixus?

No.

 

[robbob2112]

The short answer for me is no and yes. As far as I am concerned a class T is required with the potential of these batteries, I am putting one in each of my new batteries.

The real trouble with this and the other recent one in up in smoke is the current from the other packs sending all their current through the cable to a shorted pack. IMO this means the class T or equivalent is required on each pack.

 

[ricardocello]

IMO this means the class T or equivalent is required on each pack.

I’ve just ordered three Class T 125A JLLN littelfuse fuses for my 3 EG4-LL v1 packs ($168 total).
I’ll bolt them on with custom busbars.

These rackmount units have a Chint 125A breaker. I don’t trust them to be anything but an off/on switch.
I already had a 300A Class T on the positive busbar going to 4/0 cable leaving the rack.

 

[S Davis]

The real trouble with this and the other recent one in up in smoke is the current from the other packs sending all their current through the cable to a shorted pack. IMO this means the class T or equivalent is required on each pack.

Yes exactly, if you look I was saying no I didn’t trust the breaker and yes to a class t on each pack. That is what I am doing, breaker for disconnect and into class t and front terminal.



I was hoping the breakers would be enough but I just don’t trust them. Now I just need 12 class T fuses and holders.

 

[chicagoandy]

Cheaper from Mouser than amazon and cheaper without the "Blue Sea systems" name markup.... fuses are much cheaper there as well.

https://www.mouser.com/ProductDetail/Bussmann-Eaton/CFCOVER-1R?qs=zijbFIqa2JEOjMDsOT7upA%3D%3D

https://www.mouser.com/ProductDetail/Bussmann-Eaton/CFBAR1-250SP?qs=r5DSvlrkXmKMfmwp3Zb%2FBw%3D%3D

Interesting site, great prices on the MRBF, but very expensive for the class-t. Thanks for the tip.

 

[Ampster]

but very expensive for the class-t.

Yes, Amazon was less expensive for the Class T than Mouser.

 

[robbob2112]

Yes exactly, if you look I was saying no I didn’t trust the breaker and yes to a class t on each pack. That is what I am doing, breaker for disconnect and into class t and front terminal.

View attachment 212749

I was hoping the breakers would be enough but I just don’t trust them. Now I just need 12 class T fuses and holders.

I assume this picture is before you tightened down the bolt for the fuse itself? The washer isn't compressed fully which makes it either not torqued yet or not enough room before the studs bottom out.

Edit - I see those are nuts that are not tight yet

And look at it this way, the Class T is a one time investment in your future.

 

[S Davis]

I assume this picture is before you tightened down the bolt for the fuse itself? The washer isn't compressed fully which makes it either not torqued yet or not enough room before the studs bottom out.

Edit - I see those are nuts that are not tight yet

And look at it this way, the Class T is a one time investment in your future.

Yes that picture is just dry fitting, if you look it is not connected in the breaker yet either. I’m doing 12 boxes so needed to do a mockup.