Emerson VERTIV Liebert Mini-Mate2 MM2CF User Manual

System Performance Microprocessor Controls
51 Liebert
®
Mini-Mate2
™
7.0 SYSTEM PERFORMANCE MICROPROCESSOR CONTROLS
This section provides a detailed description of how the Liebert Mini-Mate2 responds to operator
inputs and room conditions.
7.1 Temperature Control
7.1.1 Cooling/Heating Required
The temperature control program for the microprocessor is based on a calculated percentage
requirement for cooling/heating.
7.1.2 Cooling Operation (Cooling, Compressorized Direct Expansion and Chilled Water)
Cooling is ACTIVATED when the temperature control calculates a requirement for cooling of 100%. It
is DEACTIVATED when the cooling requirement drops below 50%. The optional hot gas bypass is
energized when a call for cooling occurs unless there is also a call for dehumidification.
7.1.3 Heating Operation
Electric Heat or Hot Water
The reheat stage is ACTIVATED when the temperature control calculates a requirement of 100%.
The reheat is DEACTIVATED when the heat requirement is 50% less than the activation point.
Ground Current Detector (GCD)
A Ground Current Detector is factory-installed on all 1-ton through 3-ton Liebert Mini-Mate2 units
with reheat. The GCD detects reheat leakage current and shuts down operation of the reheat. A
steady green LED indicates that the reheat is operating properly. A red LED indicates that the reheat
has failed and both the reheat element and GCD need to be replaced.
Figure 30 Ground current detector
Table 23 Cooling and dehumidification load response of hot gas bypass
Situation Response
Cooling only ON
Dehumidification only OFF
Cooling with Dehumidification OFF
!
WARNING
Risk of heater element failure, smoke and fire. Can cause building and equipment damage,
injury or death
Do not remove or disable the ground current detector.
Reheat
Assembly
ALM
ALM
24G
24G
24H
24H
24DH
24DG
Current
Sensing
and
One-Shot
Control
Circuit
Jumper
CT1
CT2
Current
Transformer
BR-Backup
Contactor
If Present
RH-Reheat
Contactor
or
SCR Control
RH Contactor or
BR Contactor as
Required
Liebert
Unit
Control

Emerson VERTIV Liebert Mini-Mate2 MM2CF Specifications

General

Brand	Emerson
Model	VERTIV Liebert Mini-Mate2 MM2CF
Category	Air Conditioner
Language	English