Join Date: Dec 2002
Thanked 0 Times in 0 Posts
Rep Power: 18
A/C Light switches
There IS a difference between switching AC & DC. Use only DC Rated switches on DC circuits, and only Inductive Rated Switches on Motor Circuits.
You need a 20 Amp Minimum 12V DC Inductive Rated (as opposed to Resistive) Switch c/w W.P “Boot”.
In AC circuits voltage and current vary in a sinusoidal pattern. The 60-Hz rate of voltage and current means they both cross the zero reference 120 times a second. Therefore, there is only a remote chance of closing or opening a switch when the voltage and current are at their maximum.
There is a different situation with DC circuits, however. The voltage and current in a DC circuit generally do not vary. They are always at their rated levels. Compared to AC circuits with the same voltage and current, DC circuits handle 1.414 times the power.
Sasha_V Is totally WRONG when he states that “...a switch is a switch is a switch in terms of AC or DC...”
And, in North America, domestic AC light switches are typically rated 15A or 20A @ 120VAC (not 10 or 15A).