TCI HG7 - Manual (Page 27)

P O W E R M O N I T O R P A C K A G E O N L Y
POWER MONITOR OPTION HG7 I, O, & M Manual 25
Control Wiring
Control Power
An internal control power transformer is provided to supply 120 VAC single-phase power for the
contactor, Protection Monitor, and cooling fan(s). Fuses are provided on both the primary and
secondary sides of the control transformer.
Filter Enable Input
An auxiliary N.O. run contact from the drive should be connected to the Filter Enable input to enable
the HG7 “XM” Option only when the drive is running.
Fault Alarm Relay
A Fault Alarm relay is included in the HG2 Protection Monitor which is furnished as standard in
“XM” Option units rated over 20 kVar. The Fault Alarm relay is energized when control power is
applied to the HG7 and the HG7 is operating properly. A set of form C contacts is provided for
customer use.
Determine how the Fault Alarm contact will be used. It may be connected to the drive external fault
input or to some supervisory control or alarm annunciation equipment. A HG7 fault alarm indicates
that the HG7 filter has been disabled by the HG2 Protection Monitor. If the drive operates while the
HG7 is disabled, increased harmonic distortion of the power source may have adverse effects on the
power distribution system components and other equipment. To guard against the effects of increased
harmonic distortion, consider connecting the HG7 to automatically shut down the drive if a fault
occurs. The best alternative to shutting down the drive is to provide an alarm to personnel who will
promptly investigate the problem.