Okay you don't have to be an EE but it is beyond basic stuff.
I have rewired my control panel to control 2 elements and the pump at the same time, by adding some switches. I think the switches are SPDT with center off. One switch chooses either the pump or the HLT element. The other switch chooses the Keggle element and I have nothing on the other pole.
Both elements are controlled through a contactor switches and one has an SSR.
I want the other pole on the one switch to be able to turn on both elements, so I can run the elements and pump at the same time. One problem I am having is the added wire to the contactor will allow the current to run back to the other contactor when I am trying to run just one element at a time.
I have come up with a way to isolate the current but it uses a relay switch. I recall diodes can operate as an electrical check valve to ensure electricity can travel only one way. Can a diode be used in line to prevent the current from back tracking along the wiring?
From my limited knowledge, (web research) I know i need a resistor for use in A.C.. Is putting a diode in line a good idea, or should i just go with the relay switch? If a diode will work which diode/resistor will be appropriate for running this contactor?