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HW dump off pv panels
I'm currently in the middle of setting up an off-grid pv/battery/inverter system, and need to know what equipment to get for a power dump into a water heater after the batteries are charged.
6k watts of panels, Magnum 4400w inverter with Magnum minipanel, Magnum PT100 charge controller, 48v battery bank. Water heater circuit will extend 100 ft from the shed housing inverter/charger/batteries.
I'm aware that the charger has a relay switch which can be programmed with remote control (which I have) to engage at a given state of charge and disengage at a given SOC. I plan to use this to operate a separate relay switch to power a heating element in the water heater when the batteries are charged, but not when the batteries are below full charge.
The relay in the charger does not provide power, it opens or closes a separate circuit with power provided from another source. It's just a switch. The relay can accept 48vdc from my inverter panel, but limited to .5 amp. I'm guessing my best route is to pull a low amp dc circuit off the Magnum inverter panel at 48v, switched at the charger relay, which will operate an SSR that will switch a 240vac 30 amp circuit (or less amp) to heat water.
Suggestions for how else to configure are welcome, but I can't at this point run a dc circuit to the water heater, 100 feet away. I'd have to dig for another conduit. I'm willing to accept the inefficiency of the ac circuit through the charger/inverter.
With the plan I have in place-
-can you specify an SSR that takes 48vdc control circuit under .5 amps, and switches a 240vac circuit at max 10 amps (or less). Prefer higher quality/price. What brands/suppliers do you prefer?
-at what SOC voltage should the relays engage/close the water heater circuit, when the batteries are charged?
-at what SOC voltage should the relays disengage/open the water heater circuit to avoid draining the batteries?
Thanks
6k watts of panels, Magnum 4400w inverter with Magnum minipanel, Magnum PT100 charge controller, 48v battery bank. Water heater circuit will extend 100 ft from the shed housing inverter/charger/batteries.
I'm aware that the charger has a relay switch which can be programmed with remote control (which I have) to engage at a given state of charge and disengage at a given SOC. I plan to use this to operate a separate relay switch to power a heating element in the water heater when the batteries are charged, but not when the batteries are below full charge.
The relay in the charger does not provide power, it opens or closes a separate circuit with power provided from another source. It's just a switch. The relay can accept 48vdc from my inverter panel, but limited to .5 amp. I'm guessing my best route is to pull a low amp dc circuit off the Magnum inverter panel at 48v, switched at the charger relay, which will operate an SSR that will switch a 240vac 30 amp circuit (or less amp) to heat water.
Suggestions for how else to configure are welcome, but I can't at this point run a dc circuit to the water heater, 100 feet away. I'd have to dig for another conduit. I'm willing to accept the inefficiency of the ac circuit through the charger/inverter.
With the plan I have in place-
-can you specify an SSR that takes 48vdc control circuit under .5 amps, and switches a 240vac circuit at max 10 amps (or less). Prefer higher quality/price. What brands/suppliers do you prefer?
-at what SOC voltage should the relays engage/close the water heater circuit, when the batteries are charged?
-at what SOC voltage should the relays disengage/open the water heater circuit to avoid draining the batteries?
Thanks