the spec sheet only mentions DC rating
asked
What is the AC rating for the relay of smart solar MPPT RS 450/100 and /200 ?
It is a DC charger, why would it have an AC rating?
Because you might use the relay to switch an AC load, like a light?
That is not its purpose, as far as I am aware.
From the manual:
Programmable relay which can be set for general alarm, DC under voltage or genset start/stop function. DC rating: 4A up to 35VDC and 1A up to 70VDC
It could be an AC control voltage too, for a generator start signal. The AC rating is completely omitted from the manual.
It will be beneficial to state the AC rating, even if just 100mA@24VAC. If it is entirely unsuitable for AC operation (which is unlikely), it will still be beneficial to state it in the specification.
In other inverters, like MultiPlus II 48/5000, where they provide the same DC ratings, they are also saying the AC ratings.
So, it could be assumed that they are using the same type of relay in Multi RS and its ratings are the followings: AC rating: 230V / 4A, DC rating: 4A up to 35VDC and 1A up to 60VDC.
Which seems pertinent, because the flame extinguishing necessities for AC are more relaxed than in the case of DC.
Alex
Thanks Alex: this is really helpful.
I will use this to steer several 120V-coil power relays that will switch loads from inverter to grid and back depending on battery voltage, because in my country we cannot connect any solar to the grid at all.
