Emerson CW089, Design Manual

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Guide Specifications—Chilled Water Environmental Control System
Liebert
®
CW
™
System Design Manual 116
4.9 CHILLED WATER VALVE FEEDBACK—OPTIONAL
The control shall be designed to monitor valve feedback. The control shall notify the user of valve failure
through the local display and remote monitoring.
4.10 DUAL CHILLED WATER VALVE STAGING—OPTIONAL
The control shall provide special staging options on dual chilled water valve applications. The chilled-water
valves may be staged in parallel, cascade or alternate lead operation.
Parallel control shall allow both chilled-water valves to operate at the same time, following the same
open/close command as the room conditions deviate from the setpoint.
Cascade control shall allow the valves to operate in stages. Only 1 circuit shall be operated to maintain the
conditioned space temperature. If the room condition is not held with 1 circuit in operation, the control will
automatically stage a second valve on to maintain room conditions. An automatic timer may be used to
alternate the lead valve to keep equal component run time.
Alternate operation shall allow 1 circuit to work as lead and the second circuit to act as backup. The lead
valve will rotate based on valve run time, or the user can alternate the lead valve using a customer input
connection.
4.11 REMOTE MONITORING—OPTIONAL
A factory-installed communication card shall be provided for monitoring and/or control. The communication
card shall be capable of connecting to the Building Management System/Building Automation System
using the following protocols:
• BACnet IP —BACnet over Internet Protocol
• BACnet MSTP —BACnet Master-Slave/Token-Passing (MSTP) communications protocol over a RS-
485 serial network (also known as BACnet MSTP RS-485)
• Modbus RTU —Modbus Remote Terminal Unit (RTU) communication protocol over a RS-485 serial
network (also known as Modbus RTU RS-485)
• Modbus TCP —Modbus Transmission Control Protocol over Internet Protocol (also known as Modbus
TCP/IP)
• SNMP
• YDN23 —YD-T-1363 specification protocol (also known as YD/T 1363)
The communication card shall be capable of connecting to two of these protocols at once.
4.12 POWER MONITORING—OPTIONAL
The unit shall be equipped with factory-programmed/installed power meters to monitor power
characteristics for either individual component or total unit. These meters shall allow the user to monitor
meter connection status, input undervoltage, input RMS voltage leg-to-leg and leg-to ground, input current
for each phase, energy consumption in kilowatt hours and instantaneous power in watts. In multi-unit
applications, a phase loss protection routine shall place a unit into standby mode in the event that phase
loss is detected.
4.13 HIGH TEMPERATURE SENSOR—OPTIONAL
The high temperature sensor shall immediately shut down the environmental control system when
activated. The high temperature sensor shall be mounted in the electrical panel with the sensing element
in the return air.