Hi there, all,
I'm currently renovating a device that controls a couple of small, low voltage, permanent magnet motors via foot switches. Each motor has its own section of the power supply, delivering symmetrical positive and negative voltage rails with respect to a common 0 volt rail. Then each motor channel has a pair of foot switches, single pole, closed while pressed, one for 'up' and the other for 'down'. The switches are interconnected so as to prevent connection conflicts. (As soon as I can, I'll scan and post my intended circuit diagram.)
My dilemma is whether to wire the system so that when no motor movement is required, i.e. both foot switches are in the NC position, both sides of the motor are connected to the relevant 0 volts. This would rapidly bring the motor to rest - however, I dimly remember a theory that the current that would flow through the short-circuited armature would, in time, demagnetize the motor's field magnet.
The motors are proprietary and obsolete and no spares are available. They are incorporated in mechanisms for which mechanical modifications are effectively 'out of bounds'. So I am anxious to avoid anything that would shorten their lives.
I could incorporate a resistor in the circuit but this would take space and would require adding mounting tags in an already crowded enclosure.
Has any Modder out there trodden this path before? I welcome any informed comments.