Teamwork Mode 2; Figure 94 Teamwork Mode 1 With Two Cooling Units - Emerson Liebert CRV User Manual

Figure 94 shows how two cooling units work together in Teamwork Mode 1. Since Unit 1 and Unit 2
are available to operate, the master unit, Unit 1, averages the temperature and humidity sensor
readings from each unit.
The master unit determines that a 60% call for cooling is required for the system. Since there are two
available cooling units, each unit makes up half of the system proportional band; Unit 1 handles 0-
50% system call for cooling and Unit 2 handles 51-100%. For every 1% system call for cooling, each
unit provides 2% of its total cooling capacity.
The 60% system call for cooling exceeds the 50% Unit 1 can provide, so Unit 1 operates at full
capacity. The remaining 10% system call for cooling (60% - 50% = 10%) is handled by Unit 2. Unit 2
responds by operating at 20% cooling capacity (50% ÷ 10% = 20%).

Figure 94 Teamwork Mode 1 with two cooling units

- temp.
0%
Setpoint

11.4.4 Teamwork Mode 2

Teamwork Mode 2 is designed to prevent units within a group from working against each other or
"fighting." It is best applied in large rooms with unbalanced heat loads. In Teamwork Mode 2, all
parameters are shared equal to Mode 1, and Unit #1 averages all of the available unit sensor readings
on the network to define whether there is a cooling, heating, dehumidification or humidification
request.
If there is a cooling request, all units are released to start cooling resources according to their own
temperature readings; heating is disabled for all units and vice versa. Same for humidity control.
If the network average would ask for 0% proportional band, the most demanding request (highest or
lowest temperature of all units, highest or lowest humidity of all units) would be used to define the
operation to be performed.
Teamwork Mode 2 does not rotate; unevenly distributed working hours to be expected. AutoSet will
not adjust the proportional band in this mode.
NOTE
In Teamwork Mode 2, all units must have the same setpoints. The units' proportional band,
deadband and related settings may differ.
System proportional band
heating
1/2 Proportional Band
-100 %
Unit 1 Deviation : 100%
C1 C2
cooling
1/2 Proportional Band +100%
System Deviation : 60%
0%
1/2 Proportional Band
Setpoint
Unit 2 Deviation : 20%
C1
+temp.
0%
1/2 Proportional Band
Setpoint
101
Operation in Teamwork Mode
100 %
60%
0%
+temp.
+100%
C2
cooling
+temp.
+100 %
Liebert
® ™
CRV