Breakaway Switch Confusion.
I recently purchased a 2003 25' Coachman travel trailer. The breakaway switch was crushed on the trailer so I replaced it but I am confused about the power for it. The old one only had 2 black wires c...
Forum Discussion
dodge guy wrote:
The brake magnets will in fact weaken if left on for longer than what is recommended. they will not cook. but they will weaken if left on for lets say a few hours.
Electro magnets do not "weaken" from use, intermittent or permanent on.
They do however have a surface which DOES wear out, that is the surface of the magnet which touches and slides on the inside drum surface when the electro magnet is energized during braking. That surface is a wear item and over tens of thousands of miles the electro magnets may need replaced.
Electro magnets failure mode is shorts or an open in the wire.. A short is going to cause the electromagnet to draw more current, more current means more strength to the point of complete failure.
An open winding means no current flows which means zero magnetic field.
So called "permanent" magnets are a different thing altogether, those magnets must be "charged" when manufactured, they can and do lose some magnetism over their life gradually unless they are exposed to a very strong alternating magnet field and that AC field removes the magnetism.. Model T engines use that type of magnet in the magneto to run the engine.
