Emerson Vission 20/20 Operation And Service Manual page 221

Appendix B • Vission 20/20 Application Procedures
VPLUS (DC Motor) Setup Procedure for
20/20 Panel
INTRODUCTION
This document provides guidelines to setup a DC Motor
VPLUS oil cooling system control on the Vission 20/20
panel.
SCOPE
The Vilter standard VPLUS oil cooling system uses a
mini-temperature controller to monitor both discharge
and oil injection temperature, averages those tempera-
tures and compares the average to a setpoint. Based on
the error from the setpoint, the temperature controller
Figure B-41. Standard VPLUS Oil Cooling System Wiring (Eliminating Temperature Controller)
Vission 20/20 • Operation and Service Manual •Vilter/Emerson • 35391SC 2.0
then sends a varying 4-20ma signal to a Dart speed con-
trol board – which varies the speed of a DC motor. The
speed of the motor controls the amount of liquid refrig-
erant that is injected into the compressor to provide oil
cooling.
The Vission 20/20 has oil cooling controller algorithms
built into the program, and therefore allows for removal
of the temperature controller from the VPLUS panel.
This document provides instructions to help setup the
Vission 20/20 for VPLUS control.
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