So after much discussion, and finding a good price on dual SSR's (which is the safest way to run for 240v 2-pole heater elements), I need to know if the following diagram below will work for wiring the dual SSR to the BCS-460.
What I am wondering is if I can split the output to two jumpers on the dual SSR. Or, am I going to have to dedicate one output to each hot leg of a heater element? If that is the case of having to use one output for each hot leg, if you want to run three 220v heater elements in the safest way possible and to code, you will not be able to have the BCS control any other output processes So.... when will the expansion board be ready!?!?
Let me know! Thanks so much... I am eager to test this bad boy out!
One output can control both legs of your dual SSR. That is, as long as the 20mA output current limit is not exceeded. Do you have datasheet for your SSR? Most SSR's are rated at a maximum 3-4mA of control input current, so you can typically control upto 5 SSR's with one output. But it depends on the SSR.
Thanks for the quick response... I am hoping to get it wired this weekend, and then next week work on process control, so next weekend I can do at least a water test! Thanks again.
There was recently a question about this on another board. People were worried that connecting the BCS GND pins to earth ground would somehow provide a path from ground to neutral. However, the BCS GND is not connected to the 'neutral' line. The 2 prongs of the 'wall wart' that power the BCS are attached to the primary coil of a transformer, and the secondary coil is fed through a rectifier/regulator to create DC voltage. This is all inside the wall wart. In fact, transformers are used in this way to isolate AC circuits.
So should the BCS GND pin be connected to earth ground? Doesn't really matter. Personally, I don't because it doesn't need to be, and it may slightly increase the risk of noise into the DC circuits. Although I've never witnessed it causing ill effects.
My electric background prior to this was 12VDC... everything I learned from that to make sure EVERYTHING shared a common ground (the vehicle frame/chasis). So when I did the diagram I was not thinking that the BCS is actually a DC device and the input electricity was AC and there might be an issue with the grounding between the too.
Based on ECC, I do not think I will be grounding the BCS to the input power common ground. However I will be grounding the control panel case to the common ground. That is what I should do, correct?
So.... when will the expansion board be ready!?!? 
