Is battery equalizer required for batteries in series?

[HRTKD]

• Working Condition: The working condition for the battery switch is 12V-60V voltage and 0-300A

https://a.co/d/fuCknn6

Yes, the specs are right. Up to 60v DC and up to 300 amps. Would I use it? Probably not. I paid five times that for a Blue Seas disconnect switch. Now maybe I overpaid, but Blue Seas is a trusted vendor here on the forum. I would be reluctant to put my trust in a $10 disconnect switch. If you used the switch only when there was no load/charge it would work. But that one time that you need to shutdown the system under a heavy load/charge? I think the potential in your system is beyond what that $10 switch can handle.

 

[Partimewages]

I don't think they offer anything above 48 volts.

 

[HRTKD]

I don't think they offer anything above 48 volts.

You are correct that they don't. Once the voltage gets to a certain point ( > ~48 DC) the ability to handle the arc get's a lot more important. Something like that.

 

[wattmatters]

BESS DC Breaker | BENY New Energy

Home Battery energy storage systems (BESS) DC Breaker MANUFACTURER Battery energy storage systems are rechargeable battery systems that store energy from the solar system and provide that energy to a home or business. BENY Electric BESS dc breakers are designed for applications including solar...

www.beny.com

 

[garetwo]

Yes, the specs are right. Up to 60v DC and up to 300 amps. Would I use it? Probably not. I paid five times that for a Blue Seas disconnect switch. Now maybe I overpaid, but Blue Seas is a trusted vendor here on the forum. I would be reluctant to put my trust in a $10 disconnect switch. If you used the switch only when there was no load/charge it would work. But that one time that you need to shutdown the system under a heavy load/charge? I think the potential in your system is beyond what that $10 switch can handle.

I also doubt that switching it under load would be a good idea, I think just isolation AFTER all loads are turned off. I think there was a thread in the forum on the difference between disconnects and isolation. I can see paying five times more for one you can switch under load.

 

[garetwo]

BESS DC Breaker | BENY New Energy

Home Battery energy storage systems (BESS) DC Breaker MANUFACTURER Battery energy storage systems are rechargeable battery systems that store energy from the solar system and provide that energy to a home or business. BENY Electric BESS dc breakers are designed for applications including solar...

www.beny.com

They do not show a price, but I think these breakers are expensive? Also, they look like they are for the output side of the PV modules, not a 48VDC battery set?

 

[wattmatters]

They do not show a price, but I think these breakers are expensive? Also, they look like they are for the output side of the PV modules, not a 48VDC battery set?

If you want a quality DC breaker for your battery system, then expect to pay some money. DC breakers are not something to cheap out on.
How much was spent on batteries and inverter/charge controller?

500V 250A 2 Pole DC IP65 DC Circuit Breaker (they come with an outdoor rated enclosure):

BENY BDM Series: DC Circuit Protection for BESS | BENY New Energy

BENY New Energy's BDM series, including BDM-125 and BDM-250, offer robust DC circuit protection for BESS, with a 500V rating and up to 250A current capacity.

www.beny.com

It retails in Australia for ~$A169 including the enclosure which is about US$110. Pretty common for stuff to cost more here than there.

There is also a 125 A version.

The current rating is user adjustable, so if e.g. you want to limit your system to 200 A, you can dial the 250 A breaker down to that rating.

I'm sure there are cheaper alternatives but DC breakers and/or fuses are not to be skimped on.

 

[HRTKD]

The higher the voltage, the more expensive some components become.