Johnson Controls MR4PMUHV Manual

Temperature/Defrost Control with Relay Pack
The MR series temperature controls are designed for
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.
One convenient package consolidates the functions of
a thermostat, a digital temperature readout device,
a timer, and a defrost termination switch. This
microprocessor based control offers innovative
features and state-of-the-art technology.
Single Package
Mounting Flexibility
Easily Readable Temperature
Display
Accurate, Interchangeable
Temperature Sensor
Heavy Duty Relays
Alarm Management
Functions
© 1998 Johnson Controls, Inc.
Part No. 24-8790-18, Rev. C
Code No. LIT-125190
MR4PMUHV Electronic
Features and Benefits
Provides the functionality of multiple components
at a cost effective price
Allows control and relay pack to be mounted
together or separately, facilitating multiple
configurations
Displays both evaporator and process
temperature quickly; helps troubleshoot system
Provides accurate control performance with up to
300 feet of wiring (An offset is provided for longer
wiring.)
Allows direct control of compressors, fans
heaters, and alarms; reduces installation time
Provides both local alarm codes and a relay
closure that can be used to trigger a remote
alarm or a dial-out modem
Temperature Controls Section A
Product/Technical Bulletin
Figure 1: MR4PMUHV-12 Electronic
Temperature/Defrost Control with Relay Pack
Master Catalog 125
Issue Date 1098
1
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