Emerson VE User Manual

All critical information is stored in nonvolatile memory. Setpoints, setup parameters, and component 

run hours are kept inside the microcontroller in EEPROM. Information retained for the alarm history 

is kept in non-volatile RAM. 

Equipment options are selected and enabled using DIP switches 1 to 7. These are located at the upper 

left of the control board and are labeled SW1. Switch 1 is at the top. These switches are factory set 

and should not require any user changes. The setting and function of the switches can be read from 

the LCD display and are also described in more detail in 4.8.4 - DIP Switches.

Active control outputs are indicated with LEDs on the lower section of the control board. Each LED is 

lit if the control output is active (on). The LEDs assist in troubleshooting the system.

The control system uses a two-wire, RS-422 channel to communicate with remote monitoring systems 

via Liebert Site Products. This communication, directly out of the control, uses a proprietary protocol. 

Your unit can have a variety of different Site Product devices wired to this port depending on the 

monitoring system you are using. 

• SiteScan Centralized Monitoring System—Stand-alone facility monitoring system
• SiteLink BMS Interface Module—For Modbus or BACnet communication to a third party moni-

toring system

• OpenComms Network Interface Card—For Ethernet connection using SNMP protocol
• OpenComms D.O. Interface Card—For discrete outputs of status and alarm conditions
• Mini-Remote—Stand-alone individual unit remote monitor
• ECA2 Communication Adapter—For remote service monitoring directly or via a modem

Consult the user manual of the appropriate device for specific installation and operation information. 

R5

Heat Rejection

LLSV1

Liquid Line Solenoid Valve 1

HGBP1

Hot Gas By-Pass or Compressor Unloader Valve

C1

Compressor 1

C2

Compressor 2

RH1

Reheat Stage 1 or Hot Gas Reheat Solenoid

RH2

Reheat Stage 2

RH3

Reheat Stage 3 

HUM

Humidifier

HGBP2

Hot Gas Bypass 2 or Compressor Unloader Valve 2

FAN

Main Fan

HMV

Humidifier Make-Up Valve

LLSV2

Liquid Line Solenoid Valve 2