Originally Posted by MazdaMatt
It scares me a bit when people ask questions about this stuff on the internet. Sorta one of those "If you don't know, you shouldn't be asking online" type of subject. Get ahold of a friend who understands electricity.
This diagram is for single-phase AC. If you've got red/black/white/gnd, you have 2-phase AC and you'd need 2 solid state switches, one for black and one for red.
(I may be confused if your building code calls for black=hot, red=neutral, but AFAIK, white is always neutral and red is for a second voltage course, usually opposite phase).
A quick electrical primer, for non electricians:
Nearly all US localities follow the NEC, National Electrical Code. There are differences from residential to commercial, but the code is pretty standard.
The color coding for US is:
L1 = Black, L2 = Red, L3=Blue, Neutral = White, or grey, Ground = Green, green/yellow striped, or a bare copper wire.
and alternately (generaly for 480):
L1 = Brown, L2 = Orange (delta), L3 = violet (wye) or Yellow, Neutral = Grey, or white, ground = Green[href=http://en.wikipedia.org/wiki/Three-phase_electric_power]
There is 3 phase, Which is commercial 480VAC3phase, consists of three legs ~280VAC. Measuring from one phase to the other gives you the 480.
a-b b-c a-c are the three phases. Used for large motors and equipment.
And there is single phase.
Nearly all residential electric service (in the US) is single phase.
Single phase can be 120VAC1phase or 240VAC1phase. If you read the electrical plate info on your stove or dryer you'll see it says 220VAC single phase. (phases symbol is o with a line through it.)
"Single phasing" is also used as shorthand by electricians to describe the fault when one leg of a 3 phase circuit is lost. Causing in to only have 1 of the 3 phases. (ie C leg drops. A-B good, B-C bad, A-C bad.)
There is no such thing as two phase AC in residential North American power.
Three-wire, 120/240 volt single phase power used in the United States and Canada is sometimes incorrectly called "two-phase". The proper term is split phase or 3-wire single-phase. The two live outputs of a 3-wire single phase transformer secondary winding are properly called "legs"
A more accurate statement would be, "if you have red and black power wires, you are dealing with 240VAC not 120VAC."
240VAC is used for a clothes dryer, large portable AC, oven, or stove. It uses two adjacent breakers tied together in the breaker panel to supply the two legs of power. (L1-neutral or L1 - L2 one phase)
Measuring either leg to neutral will produce 120VAC. Measuring the L1 to L2 will produce 240VAC.
The label "120VAC hot" in the diagram should be changed to 120VAC L1.
If you wanted to use a 240VAC heating element, you would connect the bottom terminal of the element to '120VAC L2' instead of Neutral.
The Neutral would still need to connect to the PID.
In short, yes, these are just the black and white for 120VAC, and black and red for 240VAC, wires from an electrical cord that wind up in an outlet. The type of plug and where it can plug in are determined by the voltage and current rating of the circuit you are powering. Higher current plugs usually are hard wired or have twist lock plugs to keep them from accidentally unplugging while energized.
A single SSR can control a 240VAC element because you only need it to remove one of the two legs to break the circuit.
Can I install more than one element into a single PID or do I need multiple?(if so I may hardwire a second element and only use it for boils)
Finally, I feel like there should be a ground somewhere, uh...where?
This depends on the PID. If it has multiple outputs yes, you could control another element, but you would also need a second SSR.
The trouble is, a 1500W element at 120VAC is 12.5Amps. A standard 120VAC outlet is rated at 15 amps. So you would have to run a second cord to an outlet on a different breaker.... Probably not to hard if your in the kitchen. Good luck if your in the garage.
At that point you may as well make it 240VAC anyway. The current for a 1500W element at 240VAC is only 6.25Amps. You could use a 5500W 240VAC element for the big temp jumps (23amps) and still be under 30amps the common breaker size for clothes dryers.
You could use the 5.5KW element on the pid if its two stage, or just put a switch on it and turn it off when its boiling or close.
If you need to add a 240VAC outlet ask for a quote for adding a dryer outlet and breaker, or research it and do it yourself.
Never goes without saying: Anytime you work on electricity, turn it off, unplug it or open the breaker, and use a multi-meter
to make sure its not got electricity left.