Checking Hotwire relay 50's 60's era Refrigerators

[rickgburton]

HOW TO TEST A HOT WIRE RELAY ON ANTIQUE REFRIGERATORS
When a compressor uses a "Hot Wire Relay" it doesn't use an overload because it uses a wire that's sensitive to current changes. Here’s how to check it but you should be comfortable working with live electricity and you should be very careful working with those old wires because the outside coating/casing will be extremely brittle and will crack and/or fall off the wire easily. On a Hot Wire Relay, there are "Dummy Posts". The wires on the "Dummy Posts" are under the screws just to make wire connections and are in no way connected to the relay itself. You're only concerned with the three wires to the relay proper. Look closely at the relay itself. You'll see the markings, "L" for line, "M" for motor, and "S" for start. Remove the power source from the machine. Remove the wires from the relay under the terminals marked "L" "M" and "S". Connect wires "L" and "M" together or fasten them under one of the screws on the relay for convenience. Have someone plug the machine in. Cautiously touch the "S" wire to the "L" and "M" wire. If the compressor starts, immediately remove the "S" wire. If the compressor continues to run normally the relay is causing the problem with the compressor. That style relay can be replaced with a newer solid state style relay without any problems and is still available today