Good 48vdc switch wanted

100kwh-hunter

100kwh-hunter

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I am looking for a good 48v-60v dc! switch that can handle 10A
Apparently, those switches are not existing, between shore and ship (freely translated Dutch saying)
Or dig into your wallet very deep. (40 euro is the cheapest i could find on ali)

Someone have a option?
Those 10A 250ac rocker switches??? its for ac not dc but 50V dc 10 a? can this be done?
Other options?

Thanks in advance for your answers.
Best Igor
 
Sorry some additional info:
It is for switching on and off a battery bank, 48v nominal 50ah max, so it must be bidirectional.
Most fuses are one direction, or if they are bidirectional "don't switch off under load"...
Constant currant flow will be less than 10A at max 58v
Thanks
 
You're not looking for a "switch", you're looking for a "Contactor". that's what they are designed to do, to connect/disconnect under high load
 
You could just use some low IR FET's if it is for resistive loads on DC. If it is for inductive loads you would then need to have a higher voltage rated FET and a zenner to help dissipate the energy.

The "don't switch off under load" is where it does not have much protection from the high voltage when disconnecting an inductive component. i.e. a relay coil. If the zenners are bridged across to the battery the energy would end up back in the battery (all the less than maybe one joule worth)..

Disconnect that one joule in a 1uS FET switch off and you have multi kW potential energy burst (at high voltage).

BMS switches are generally parallel low IR FET arrays - usually lacking a zenner bypass.
 
@Korishan
That was the magic word, but what is a high load?
In my opinion it is 10kwh disconnecting at 50V? under load. (Blade switch...).
I think it is clever to give some pictures and some writing about what i am up to.

I would like to expand my ess in a lot of ways.
I would like to create li ion batteries of around 2.5kwh at 48V.
2500mah*20 cells=50ah*~50v=2.5kwh?

So that i can hang them on the wall, and if i completed a other one i can just put one extra in.
I can test 10 cells complete a day, so once every 5/6 weeks i can make one of those.
For maintenance i would like to disconnect one and for safety a fuse/breaker or something.

Those ones are bidirectional and showed up after dc contactor.

20230813_093054.jpg
20230813_093017.jpg

I am also planning for this li ion section a separate busbar with his own main switch.

Due to the size of the system aldo we pull one time a day ~8kwh it means 1.5kwh per battery.
If a Daly bms is set lower it will shut off.
So i think tx60/tx90 plugs will be a nice add on? to make this complete?

Thanks in advance.
Ps the bms in the pic is more for myself to give me an idea of the total work in progress.
 
100kwh-hunter said:
hat was the magic word, but what is a high load?
In my opinion it is 10kwh disconnecting at 50V?
Click to expand...
Honestly, I'd say a high load is generally anything over 15A as most relays/switches are not designed to handle the constant arcing associated with the disconnect.

A blade switch would work too. It's similar to a contactor. The biggest difference is possibly speed and the mechanical device used to disconnect. With a blade switch, you have to move the blade a pretty decent distance for it to deactivate. The device used to make the handle move is also pretty clunky.
With a contactor, it only needs to move about an inch (2.5cm) or thereabouts to disconnect, and it uses an electromagnet to do the work. The other advantage of the contactor is that some are actually designed to be reset using the electromagnet.

If using a double source contactor, they can usually trigger and flip fast enough that most equipment won't even know there was a switching. So you could switch from grid to inverter or back and the equipment wouldn't know it. Daromer (DIY Tech & Repairs) shows this in action on his YT channel.

However, if you want something that is just a huge resettable fuse like device that is there in case there's a problem and it needs to be only disconnected and manually reactivated afterwards, a blade switch would be fine as well.

Are the blade switches for physically deactivating battery banks as you add/remove/maintenance on them?? If so, blade switch would work great for that, tbh.
 
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