JP turned on Local Power Heater in middle room to 65V, which corresponding to ~300W once actived. But, it will not output any power if the remote PID power is higher than 300W. The reason to turn it on is that, during a unexpected remote power supply failure, this local one could serve as an backup, so that the total power on heater will not drop below 300W.
Notes to TO: PID heater power is fluctuating. If the minimal point of
this fluctuation drop below 300W, Local Power Heater voltage setting
should be lowered correspondingly.