Emerson E2 - Manual (Page 72)

6-12 • E2 RX/BX/CX I&O Manual 026-1610 Rev 13 14-SEP-2011
6.3.11 XM Series of Case Control-
lers
The XM series is a set of digital case controllers for
low to medium units. The XM series control refrigeration
solenoids and defrost (electric or hot gas), evaporator fans,
lights and have an auxiliary output. These devices are
available on E2 version 3.02 and above.
6.3.11.1 XM670
The XM670 is high level microprocessor based con-
trollers for multiplexed cabinets suitable for applications
on medium or low temperature. It can be inserted in a
LAN of up to 8 different sections which can operate,
depending on the programming, as stand alone controllers
or following the commands coming from the other sec-
tions. The XM670 is provided with 6 relay outputs to con-
trol the solenoid valve, defrost (which can be either
electrical or hot gas) the evaporator fans, the lights, an
auxiliary output and an alarm output. The devices are also
provided with four probe inputs, one for temperature con-
trol, one to control the defrost end temperature of the
evaporator, the third for the display, and the fourth can be
used for application with virtual probe or for inlet/outlet
air temperature measurement. Finally, the XM670 is
equipped with the three digital inputs (free contact) and
are fully configurable.
6.3.11.2 XM679
The XM679 is similar to the XM670, but with one
relay output to drive pulsed electronic expansion valves.
The XM679 also contains two probes are dedicated for
superheat measurement and regulation.
6.3.11.3 XM678
The XM678 is similar to the XM670, but with one
stepper valve output to drive an electronic expansion
valve. The XM678 also contains two probes that are dedi-
cated for superheat measurement and regulation.