IOMM AGR-1
AGR 070A through 100A
49
Additional UNT Controller Features
Remote Stop/Start
When the remote stop/start switch is open, the controller will be in the unoccupied mode. The unit
will be enabled when the remote start / stop switch is closed and will control at the leaving water
temperature setpoint.
Unoccupied Mode
When the remote start / stop input is opened, the unoccupied mode is initiated. The chiller will
maintain a higher leaving water temperature setpoint (default 70°F) if the chilled water circulation is
maintained. The unoccupied leaving water setpoint can be changed from the Zone Terminal.
Soft Start
Soft loading limits the number of available stages when the unit is started to prevent excessive power
consumption and possible overshoot of the leaving water temperature set point. Soft loading is in
effect whenever the unit is started from an “off” cycle. When stage up starts, the controller starts a
countdown timer to indicate how long the unit has been in the cool stage mode. The number of stages
allowed during soft loading is determined by the Soft Start Capacity. The duration of the soft load
sequence is determined by the Soft Start Timer. If the Soft Start Timer is set to zero, no soft loading
will take place. The Zone Terminal is required to change the Soft Start values.
Compressor Staging
The AGR Reciprocating chiller has two refrigerant circuits and each circuit has one reciprocating
compressor. When the first stage of cooling is required, the #1 refrigerant circuit will start. This
circuit will be the first to start for the next ten starts. The Global UNT controller will then select the
#2 refrigerant circuit to start first for the next ten starts. This cycle will continue and balance the
number of starts between the refrigerant circuits. This is an automatic lead / lag control.
There are four or six stages of cooling capacity on the Global Reciprocating chiller unit. The first
stage of cooling will start the compressor of the lead refrigerant circuit. The second stage of cooling
will start the compressor of the lag refrigerant circuit. Cooling stage three will always be compressor
unloader head changing to loaded condition on the lead circuit. Cooling stage four will always be
loading of the lag refrigerant circuit.
Stage down is the reverse of the above paragraph.
Table 15, System Staging and Unit Capacity
AGR 070 - 075
AGR080
AGR 085 - 100
Unit Model
Comp #1
%Load
6 Cyl.
Comp #2
% Load
6 Cly
Unit
Cap.
Comp #1
%Load
6 Cyl.
Comp #1
%Load
8 Cyl.
Unit
Cap.
Comp #1
%Load
8 Cyl.
Comp #1
%Load
8 Cyl.
Unit
Cap.
Comp #1 Leading
Stage 1
33
0
17
33
0
15
50
0
25
Stage 2
33
33
33
33
50
42
50
50
50
Stage 3
67
33
50
67
50
58
75
50
63
Stage 4
67
67
67
100
50
73
75
75
75
Stage 5
100
67
83
100
75
86
100
75
88
Stage 6
100
100
100
100
100
100
100
100
100
Comp #2 Leading
Stage 1
0
33
17
33
0
27
0
50
25
Stage 2
33
33
33
33
50
42
50
50
50
Stage 3
33
67
50
67
50
56
50
75
63
Stage 4
67
67
67
100
50
71
75
75
75
Stage 5
67
100
83
100
75
85
75
100
88
Stage 6
100
100
100
100
100
100
100
100
100
Pumpdown Control
The AGR units have a limited recycling pump down. The pump down is activated when a circuit’s
liquid line solenoid valve is de-energized. After the circuit’s liquid line solenoid valve is de-
Содержание AGR 070AS
Страница 20: ...20 AGR 070A through 100A IOMM AGR 1 Figure 9 Typical Field Wiring with Global UNT Controller...
Страница 21: ...IOMM AGR 1 AGR 070A through 100A 21 Figure 10 Typical Field Wiring Diagram with MicroTech Controller...
Страница 22: ...22 AGR 070A through 100A IOMM AGR 1 Figure 11 Standard Single Point Connection with FanTrol...
Страница 23: ...IOMM AGR 1 AGR 070A through 100A 23 Figure 12 Standard Single Point Connection with Optional SpeedTrol...
Страница 24: ...24 AGR 070A through 100A IOMM AGR 1 Figure 13 Unit Control Schematic 2 compressor UNT...
Страница 25: ...IOMM AGR 1 AGR 070A through 100A 25 Figure 14 Staging Schematic 2 compressor 4 stage UNT...
Страница 26: ...26 AGR 070A through 100A IOMM AGR 1 Figure 15 Staging Schematic 2 compressor 6 stage UNT...
Страница 27: ...IOMM AGR 1 AGR 070A through 100A 27 Figure 16 MicroTech Controller Schematic...
Страница 28: ...28 AGR 070A through 100A IOMM AGR 1 Figure 17 Unit Control Schematic MicroTech...
Страница 29: ...IOMM AGR 1 AGR 070A through 100A 29 Figure 18 Staging Schematic 4 stage MicroTech...
Страница 30: ...30 AGR 070A through 100A IOMM AGR 1 Figure 19 Staging Schematic 6 stage MicroTech...
Страница 31: ...IOMM AGR 1 AGR 070A through 100A 31 Figure 20 Unit Control Schematic 2 compressor MicroTech...
Страница 32: ...32 AGR 070A through 100A IOMM AGR 1 Figure 21 UNT Instrument Layout See legend on page 34...
Страница 33: ...IOMM AGR 1 AGR 070A through 100A 33 Figure 22 MicroTech Instrument Layout See legend on page 34...
Страница 35: ...IOMM AGR 1 AGR 070A through 100A 35 Figure 25 MicroTech Sensor Layout...
Страница 99: ...IOMM AGR 1 AGR 070A through 100A 99 Notes...
Страница 100: ...Post Office Box 2510 Staunton Virginia 24402 USA 800 432 1342 www mcquay com...
