Ice Cube Relay

I recommend that you use copper wire. Silver does have a lower resistivity than copper at room temperature but the cost/benefit does not warrant the expense. Now how this wire should be connected is in a Set-Reset relay wiring configuration. You'll find the circuit about halfway down the page after the logic symbol equivalent.

L1
|
•---(upper float)---•
|.........................|
•---3 R|| 1--------•---(lower float)---7 (R) 2---L2
|.................................................................|
•---6 R|| 8----------------------------(M)-----•

P1----M||----------------------------(pump)---P2

(The dots are just spacers to make the vertical wires line up. R = ice-cube relay; M = motor control relay with contacts sufficient to handle the load. L1/L2 = control power. P1/P2 = motor power, assumed single-phase for 1/8hp pump. The numbers are a standard pin-out for 8-pin octal relays.)

See this thread:

http://cr4.globalspec.com/thread/31701/How-to-wire-a-120VAC-square-D-latching-relay