Emerson E2 operation manual XM Series of Case Control Lers, 11.1 XM670, 11.2 XM679, 11.3 XM678

6.3.11XM 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.

6.3.11.1XM670

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.

6.3.11.2XM679

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.

6.3.11.3XM678

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.

6-12 • E2 RX/BX/CX I&O Manual 026-1610 Rev 13 14-SEP-2011