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RSMD2R Technical Guide
OVERVIEW
RSMD2R Overview
Features & Applications
The Refrigerant System Module for Digital Compressors
(RSMD2R) can monitor and control up to two compressors
and condensers. The compressors can only be in a non-tandem
configuration. The module is designed for R410-A refrigerant.
NOTE:
The RSMD2R is for units that match all of the
following criteria:
1. Two circuits, single compressor per circuit.
2. Compressors may be any mix of fixed, two-step,
and digital.
3. Reheat is present on the second circuit only.
The RSMD2R is connected to the VCCX2 Controller. Up to
four RSMD2R’s can be connected, depending on the size of the
system. There are two E-BUS Expansion Ports which allow the
use of communicating sensors and the E-BUS Modules.
The RSMD2R provides three analog inputs, four binary inputs,
five relays, and two analog outputs. See
Figures 2 & 3, pages
8 & 9
for wiring.
The RSMD2R Module provides the following:
• Modulates the Compressors to satisfy the Suction Coil
(Saturated) Temperature. The Suction Coil (Saturated)
Temperature Setpoint is reset by the VCCX2 Controller
to maintain the Supply Air Temperature during Cooling
mode. During Dehumidification mode, it controls the
Compressors to the Suction (Saturation) Temperature
Setpoint.
•
In Heat Pump Heating mode, the RSMD2R modulates
and stages the compressors to maintain a given Supply
Air Temperature Setpoint.
• Modulates the Condenser Fan or Valve to maintain the
Head Pressure Setpoint.
• Provides alarms and safeties for the Compressor and
Condenser operation.
•
Allows connection of the Modular Service Tool SD to the
module when required communication wire is run to the
VCCX2 Controller.
• Provides a 2 x 8 LCD character display and four buttons
that allow for status of system operation, system setpoints,
system configurations, sensors, and alarms, and to change
the module’s address, if necessary.
Summary of Contents for RSMD2R
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