Control Techniques FXM5, User Manual

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FXM5 User Guide
www.controltechniques.com Issue Number: 5
The AC supply to the FXM5 controller must be isolated externally.
1.3.2 Field economy
Control of the field current can be over-ridden to a field-economy level using an external
switch. This can be used for the following purposes:
• Over-ride the normal field current when the motor is stationary in order to prevent
over-heating of the motor
• By keeping the motor warm, prevent atmospheric condensation in the motor when it
is not in use
1.3.3 Mounting arrangement
The FXM5 controller is contained in a module which must be mounted on a vertical
surface. Heat generated in the thyristors is dissipated to the air by a finned heatsink.
Ingress protection conforms to IP10.
1.3.4 Controls and indicators
Recessed preset potentiometers and LED indicators on the front panel of the module
are used for setting up and monitoring the FXM5 controller.
1.3.5 Protection
Change-over relay contacts are operated when the field current reduces to the minimum
field current set by the user. The relay contacts can be used to disconnect the motor to
prevent run-away in the event of loss of field current.