Introduction
1
1.0
I
NTRODUCTION
1.1
Description
The Liebert VFD Control Condenser, Model TCDV, is an air cooled direct-drive refrigeration con-
denser designed to reject the heat from a precision air conditioning unit to the outdoor air. The con-
denser uses a Variable Frequency Drive (VFD) to control fan speed, which provides positive
refrigerant head pressure control for outdoor ambients as low as -20°F (-28.9°C).
Figure 1
Liebert Model TCDV Condenser—2-fan
1.2
Application
The VFD Control Condenser is applied to precision air conditioning units with dual refrigeration cir-
cuits, including units with digital scroll compressors.
1.3
Features and Benefits
• Variable Frequency Drive (VFD)—Programmed at the factory to integrate fluctuating head pres-
sure signals created by compressor unloading, including digital scroll compressors, and varying
condenser capacity created by lower ambient temperatures.
• The VFD adjusts fan speed to provide stable fan speeds and condensing temperatures.
• Provides protection for motor overload and incoming power supply phase loss, undervoltage
and overvoltage.
• Built-in EMC filter—Electromagnetic emission levels comply with EN61800-3 (Second Envi-
ronment - Light Industrial Applications).
• Inverter duty motor with permanently lubricated ceramic ball bearings for reliability
• Transducers on each circuit sense refrigerant pressures, providing input to the VFD
• Standard TVSS—Transient Voltage Surge Suppression increases condenser reliability by build-
ing in a layer of electrical protection against electrical failure caused by transient voltage surges
from unconditioned power sources and atmospheric discharges.
• Standard Locking disconnect
• Contacts for monitoring VFD and TVSS alarm conditions
• Available in 2-, 3- or 4-fan, dual-circuit condenser models