Electronic Temperature Defrost Control Relay Pack (Replacement Control Relay Pack) Johnson Controls
Description
The MR series temperature controls are
designed for use with hot gas or electric heat
defrost in both refrigeration and freezer units.
Either time or temperature based defrost
termination may be selected.
The MR series incorporates control functions
such as compressor control, defrost
management, fan management, and alarm
management.
Features
• single package provides the functionality of
multiple components at a cost-effective
price
• mounting flexibility allows the control and
relay pack to be mounted together or
separately, facilitating multiple
configurations
• easily readable temperature display can
show either evaporator or process
temperature at the touch of a button
• accurate, interchangeable temperature
sensor provides reliable control
performance with up to 300 ft. of wiring (an
offset is provided for longer wiring)
• heavy-duty relays allow direct control of
compressors, fans, defrost heaters, and
alarms
• alarm management functions provide both
local alarm codes and a relay closure that
can be used to trigger a remote alarm or a
dial-out modem
Applications
These relay pack mounted controls provide
direct control of compressors up to 2 hp,
electric heater loads of up to 20 amperes, and
evaporator fan loads of up to 3/4 hp. The need
for separate relays is eliminated in these
applications.
In addition, the MR4PMUHV controls combine
the functionality of an electromechanical
thermostat, mechanical clock, defrost
termination device, and temperature readout
device with the accuracy of electronic
technology.
Replaces Part Numbers:
MR4PM12C-12
MR4PM12C-12C
CARMR4PM12C12