gjo
Junior Member level 2
I was reading basic electricity by valkenburgh and on page 68 of volume five he says" in many circuits you will see overload contacts in series with the line. These contacts are normally closed, but if the temperature of the device becomes excessive, the thermal relays will close, causing the overload relay to become energized and opening the line."
The part i dont get is where he implied the thermal relays are acting like a switch to energize the overload relay. I thought the thermal relay is an overload relay, but here he years it like the overload relay and an electromagnetic relay are used as spate relays , the thermal feeding the electromagnetic relay, and that the thermal relay is normally opened in this case. Can someone clear this up.
The part i dont get is where he implied the thermal relays are acting like a switch to energize the overload relay. I thought the thermal relay is an overload relay, but here he years it like the overload relay and an electromagnetic relay are used as spate relays , the thermal feeding the electromagnetic relay, and that the thermal relay is normally opened in this case. Can someone clear this up.