Hi, does anyone have a circuit diagram for the RB433 series. I cannot use noisy smps supplies in my environment and will be using conventional supply via the jack on board. I cannot see if the disconnect pin is in use on the PCB associated with the jack socket.
The psu’s are mounted way up the tower and normal LAN connection is not required (appart from initial programming)
But just incase I want the LAN cable connected via LAN1 (POE) and isolated via 8 pin DIL relays so that the ethernet is not terminated and radiating noise. IE the LAN is normaly lifted and isolated under normal conditions, but in the event of a power failure in the power supply aloft, the unit can then still be activated using POE.
I know it sounds complicated, but its straight forward really, but needs the help of a circuit diagram relating to the supply input circuitry.
If you are good with relays, this should not be a problem. I see exactly what you are trying to do. Not a bad idea.
I would run a second power supply line to the RB unit on the tower instead of using the PoE.
Use a small continuous duty SPDT relay on the tower PSU that requires the PSU powered up to activate (power to both N.O. terminal and positive relay coil connector), and the COMMON terminal connected to the RB. The other input (N.C.) terminal on the relay is connected to your ground PSU. When the tower PSU fails, the relay will open (change inputs actually), disconnecting your tower PSU and connecting your ground supply. If the tower PSU comes back on, it will disconnect the ground PSU and reconnect the tower PSU.
That way you won’t need to concern yourself with the RB internals.
ADD: You can do the same with PoE if you can put a relay in the cat5 lines carrying the positive power. Might want to use a DPDT relay for that.