TCI HG7 - Manual (Page 30)

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 28
The HG2 TM Protection Monitor
Introduction
Product Description
The HG2 TM Protection Monitor is included as standard in HG7 “XM” Option models rated over 20
kVar. The HG2 monitors the HG7 operation, electronically protects the power circuits, displays
performance information, and provides a control interface with the drive and/or supervisory control
system. A three-character display is provided with UP, DOWN, and SELECT keys and two status-
indicating LEDs.
The HG2 includes analog inputs for monitoring the line voltage and current and the current in the
harmonic filter. Current transformers are included in HG7, “XM” Option harmonic filter units to
provide the line current inputs. Sense windings from in the tuning reactor provide the source for the
current measurements. Voltage is measured through direct input to the HG2.
The HG2 Protection Monitor provides a local display for power monitoring at the point where the HG7
filter is connected to the power distribution system. The power monitoring display selections include
line voltage, current, real power (kW), apparent power (kVA), power factor, and harmonic distortion
parameters. The harmonic distortion parameters include total harmonic distortion (%THD) of the line
voltage and current as well as individual values of low order harmonics. Filter current and harmonic
values are also available. Three-phase average parameter values, totals, and individual phase values are
available. The HG2 calculates parameter values from the signals available at the analog inputs.
The HG2 includes contact closure inputs for Filter Enable control and for optional Over-temperature
and Door Interlock protection functions. A serial interlock connection is provided for coordinating the
protection functions of multiple HG2 Protection Monitors.
The HG2 Protection Monitor provides fault protection for the filter by disconnecting the capacitor
banks when a fault is detected. Protection functions include filter over and under-current, door
interlock, over-temperature, and others. Note that the door interlock switch and the over-temperature
thermostatic switch are optional. Fault Codes are generated on the display for ease of troubleshooting.