Maast
Compulsive Tinkerer
After a good bit of thrashing around, I'm now thinking its a very good idea to use 48v coil contactors/relays for 200A and more. The reason being is that you have a 48v source ready to hand and you wouldnt need an additional 12v power source thats burning additional juice to run. The same reasoning applies to a 24v system.
The Chargery outputs 12v to drive relays, but it can only do 3 amps. Thats fine for up to about 150A but above that the contactors are pulling 3.5-4 amps at 12v to actuate - which makes sense because you're moving big chunks of metal around.
After they actuate if you get the right model contactor the power usage goes down to about 2 watts to hold. Gigavac at least has dual coil 2 watt models at any size you could ever want. You'd need a top quality SSR to drive them like a Crydom and they run about $35 US but their power use is minimal.
Also, for the Chargerys longevity I realized I don't WANT to have the Chargery directly driving relays, the lower the amount of power flowing through it the less stressed it is and the longer it'll last, same reason I've turned off its balancing feature.
The system I'm building has every chance of being in place for the next 15 or 20 years so reliability is THE top priority and the Gigavac/Crydom route will outlast me, and use minimum power while doing it.
BTW, I'd never EVER pump 300 amps through a inexpensive Chinese SSR, the only SSR I'd trust to last for the next decade would be a Crydom/Odom quality level SSR and at that amperage they're horribly expensive, and even then I don't think I'd trust it. Industry uses contactors for big loads for good reason.
The downside to the 48v coil Gigavac/Crydom is that I'm spending more on contactors/SSRs that I did on the Chargery itself but the contactors are "where the rubber meets the road" so I consider that money well spent.
Thoughts?
The Chargery outputs 12v to drive relays, but it can only do 3 amps. Thats fine for up to about 150A but above that the contactors are pulling 3.5-4 amps at 12v to actuate - which makes sense because you're moving big chunks of metal around.
After they actuate if you get the right model contactor the power usage goes down to about 2 watts to hold. Gigavac at least has dual coil 2 watt models at any size you could ever want. You'd need a top quality SSR to drive them like a Crydom and they run about $35 US but their power use is minimal.
Also, for the Chargerys longevity I realized I don't WANT to have the Chargery directly driving relays, the lower the amount of power flowing through it the less stressed it is and the longer it'll last, same reason I've turned off its balancing feature.
The system I'm building has every chance of being in place for the next 15 or 20 years so reliability is THE top priority and the Gigavac/Crydom route will outlast me, and use minimum power while doing it.
BTW, I'd never EVER pump 300 amps through a inexpensive Chinese SSR, the only SSR I'd trust to last for the next decade would be a Crydom/Odom quality level SSR and at that amperage they're horribly expensive, and even then I don't think I'd trust it. Industry uses contactors for big loads for good reason.
The downside to the 48v coil Gigavac/Crydom is that I'm spending more on contactors/SSRs that I did on the Chargery itself but the contactors are "where the rubber meets the road" so I consider that money well spent.
Thoughts?