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48 v batt switch

Aussie

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Mar 22, 2020
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Qld. Australia
I am going to run two 48v banks of batteries. I have found a change over switch but not sure if it will work. It says MAXIMUM voltage 48v. My system will have higher voltage then that. Maybe 56v. I am having a very hard time finding a 48v dc switch. The switch I found is a BEP H.D, 4 position batt switch. SKU 113556.
Anyone know if this will handle the voltage from a 48v battery bank.
I need a switch because I have gell cells and LiFPO cells and need to keep them separate.
I prefer to source from Australia.
Anyone know of other 48v DC switchs?
 
What happens if more volts are applied then the switch can handle? Potential for fire? Or will the switch just quit working?
 
I use DC breakers for switching.

Rated for 250v.

The Schneider C65H-DC is one example. Midnite Solar also is a trusted brand.
 
I use DC breakers for switching.
The OP needs a selector switch, not a disconnect switch.

I suppose two breakers could be used. But there's a risk that both breakers could be turned on at the same time and that may or may not be an issue depending on the use case.
 
Any solution will have risk and the operator must be diligent.

I would use one C65H-DC proper amperage rated breaker for each battery, to a busbar or whatever you are connecting. More information is needed but I think this is likely the best option.

Not sure what your use case is but if the batteries will not be used at the same time this should not be an issue. If you want to parallel the two batteries you must be sure they are at the same state of charge before flipping both breakers on at the same time.

The described option, of using an underrated switch which could fail open or fused close is a hard no for me.

Another poor option IMHO is one of these:


They are AC switches and extinguishing an arc from high voltage DC would likely be an issue.
 
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missed that... sorry OP. There are none. Apparently.
sounds like two breakers with a breaker "lockout" would work. this is standard on a outback power wall switching from grid to battery...
 
Here is an expensive idea - get two relays like Kilovac EV200AAANA or a gig vac (except the 48v one), then wire a single pole double throw switch so you choose which relay & battery to engage.

Told ya it would be pricey.
 
I really want a switch to be able to switch between battery banks. Blue sea are "not certified by UL for over 48 v." As i can not find any switch certified over 48v , In am thinking of using the bluesea one that is good up to 48v. If the consequences are just a failed switch, okay. Is there any chance of fire? That of course is not okay Any help on this matter is greatly appreciated.
On another topic, Anyone know of any videos that explain clearly, for someone with limited knowledge, The whole process of hooking up and setting up a Daly 250 amp , smart BMS? Once again Thanks.
 
I think 48V is primarily a magic number - you'll die if you contact a wire with 49V, but not if only 48V, something like that.
There is greater requirement for excluding access by unqualified individuals at higher voltage.

The other issue with increasing DC voltage is inability to extinguish and arc, stop current flow. I suggest not using any such switch to make/break when current is flowing.

Lithium batteries and inverter capacitors, may cause some arcing and burning of contacts. Consider a precharge circuit.
 
Thanks Hedges. I guess the only option for me is curcuit breakers as 48v switch's are just not available.
 
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