TCI HG7 - Manual (Page 24)

C O N T A C T O R & C P T O P T I O N
CONTACTOR & CPT OPTION HG7 I, O, & M Manual 22
Contactor Option (STC)
STC Option Models
This model is identified by the suffix “STC” in the part number. The STC version provides a contactor,
control power transformer and connection terminals in the filter trap circuit which allows the VFD user
to control the insertion of the HG7 filter’s trap circuit through the use of a relay contact in the drive. It
is recommended that the drive contact be programmed to open the contactor below 33% motor power.
For variable torque (fan) loads this will be approximately below 70% speed, so the at-speed contact
may be used. This reduces the possibility of leading power factor interacting with other devices on the
power system and enables the user to perform trap circuit maintenance without shutting down the
entire drive system.
Product Description
HG7 STC Option Harmonic Filter
The HG7 harmonic filter is a drive-applied harmonic filter designed and developed by TCI to reduce
the harmonic currents drawn from the power source by variable speed drives. The HG7 STC option
harmonic filter is for 200/208, 230/240, 460/480 volt or 575/600 volt systems (60 Hz) or 380 –
415Volt systems (50 Hz). It is suitable for use with 3-phase diode bridge rectifier loads such as PWM
AC drives.
The HG7 harmonic filter is a passive filter connected in series with the input terminals of a variable
speed drive or several drives that operate as a group. It is designed to provide a low impedance path for
the major harmonic currents demanded by the drive. The filter is a stand-alone device that can be
furnished in its own enclosure and mounted adjacent to the drive. It is also available on an open panel
for mounting within an enclosure with the drive or other equipment.
The HG7 STC Option consists of the following standard features and components.
♦ A KDR input series reactor to prevent system interaction and improve filter performance.
♦ An L-C harmonic filter circuit with:
A TCI 3-phase tuning reactor specifically designed for the HG7
High-endurance, harmonic-rated capacitors
♦ Bleeder resistors to ensure safe capacitor discharge upon filter shutdown, located on
capacitors.
♦ Filter enable/disable contactor with protection and drive interlock provisions.
♦ Cooling fans (on select models) to ensure adequate cooling and safe operating
temperatures.
♦ Control transformer for fan and control voltage power.
♦ Compression terminals for ease and integrity of all power and control wiring.
♦ STCH Option has heater.