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49
WITH MOTORMASTER OPTION
20-35 Ton
Contactor
OFM(s)
Software
Board
Conrolled
Controlled
Common
MM_A_RUN
SCB Relay 1
n/a
OFM1
Any compressor ON, speed via MM_A_VFD
Common
CONDFANB
MBB Rly 5
OFC2
OFM2
# of Fans ON
Fans ON
# of Fans ON
Fans ON
Stage 1
MM1
1
OFM1
Stage 1
MM1
1
OFM1
Stage 2
MM1, OFC2
2
OFM1,2
Stage 2
MM1, OFC2
2
OFM1,2
Stages 1 and 2 start with MM_A_VFD at 50%, then modulates to control HP setpoint
Stage 2 if OAT > 75
Stage 2 if SCTA or STCB > HPSP
Stage down if SCTA/B < HPSP - 40 for two minutes and OAT < 73
Stage down starts with MM_A_VFD at 50%, then modulates to control HP setpoint
WITH MOTORMASTER OPTION
40-50 Ton
Contactor
OFM(s)
Software
Board
Conrolled
Controlled
Common
MM_A_RUN
SCB Relay 1
n/a
OFM1,2
Common
CONDFANB
MBB Rly 5
OFC2
OFM3,4
# of Fans ON
Fans ON
# of Fans ON
Fans ON
Stage 1
MM1,2
2
OFM1,2
Stage 1
MM1,2
2
OFM1,2
Stage 2
MM1,2, OFC2
4
OFM1,2,3,4
Stage 2
MM1,2, OFC2
4
OFM1,2,3,4
Stages 1 & 2 start with MM_A_VFD at 50%, then modulates to control HP setpoint
Stage 2 if OAT > 75
Stage 2 if SCTA or STCB > HPSP
Stage down if SCTA/B < HPSP - 40 for two minutes and OAT < 73
Stage down starts with MM_A_VFD at 50%, then modulates to control HP setpoint
WITH MOTORMASTER OPTION
60 Ton RTPF
Contactor
OFM(s)
Software
Board
Conrolled
Controlled
Common
MM_A_RUN
SCB Relay 1
n/a
OFM1,2
Common
CONDFANB
MBB Rly 5
OFC2
OFM3,4,5,6
# of Fans ON
Fans ON
# of Fans ON
Fans ON
Stage 1
MM1,2
2
OFM1,2
Stage 1
MM1,2
2
OFM1,2
Stage 2
MM1,2,OFC2
6
OFM1,2,3,4,5,6
Stage 2
MM1,2,OFC2
6
OFM1,2,3,4,5,6
Stage 2 starts with MM_A_VFD at 50%, then modulates to control HP setpoint
Stage 2 if OAT > 75
Stage 2 if SCTA or STCB > HPSP
Stage down if SCTA/B < HPSP - 40 for two minutes and OAT < 73
Stage down starts with MM_A_VFD at 50%, then modulates to control HP setpoint
WITH MOTORMASTER OPTION
60 Ton MCHX
Contactor
OFM(s)
Software
Board
Conrolled
Controlled
A
CONDFANA
MBB Rly 6
OFC4
OFM4
A
MM_A_RUN
SCB Relay 1
n/a
OFM3
B
CONDFANB
MBB Rly 5
OFC2
OFM2
B
MM_B_RUN
SCB Relay 2
n/a
OFM1
# of Fans ON
Fans ON
# of Fans ON
Fans ON
Stage 1
MM3
1
OFM3
Stage 1
MM1
1
OFM1
Stage 2
MM3, OFC4
2
OFM3,4
Stage 2
MM1, OFC2
2
OFM1,2
Stage 2 starts with MM_A_VFD / MM_B_VFD at 50%, then modulates to control HP setpoint
Stage down starts with MM_A_VFD at 50%, then modulates to control HP setpoint
Logic
Circuit
Controlling Output
Circuit A
Circuit B
If either of the SCT sensors has failed, then the control defaults to control based on the OAT sensor and turns on
CONDFANB when the ambient is above 65 dF and off when the ambient temperature is below 50 dF. If the SCT and OAT
sensors have all failed then the control turns on CONDFANB when any compressor is on.
Circuit
Controlling Output
Logic
Any compressor ON, speed via MM_A_VFD
Circuit A
Circuit B
If either of the SCT sensors has failed, then the control defaults to control based on the OAT sensor and turns on
CONDFANB when the ambient is above 65 dF and off when the ambient temperature is below 50 dF. If the SCT and OAT
sensors have all failed then the control turns on CONDFANB when any compressor is on.
Circuit
Controlling Output
Logic
Any Compressor ON, speed via MM_A_VFD
Circuit A
Circuit B
If either of the SCT sensors has failed, then the control defaults to control based on the OAT sensor and turns on
CONDFANB when the ambient is above 65 dF and off when the ambient temperature is below 50 dF. If the SCT and OAT
sensors have all failed then the control turns on CONDFANB when any compressor is on.
Circuit
Controlling Output
Logic
Comp A1 or A2 ON, speed Via MM_A_VFD
Comp B1 or B2 ON, speed Via MM_B_VFD
Circuit A
Circuit B
If the SCTB sensor has failed, then the control defaults to control based on the OAT sensor and turns on CONDFANB when
the ambient is above 65 dF and off when the ambient temperature is below 50 dF. If the SCTB and OAT sensors have all
failed then the control turns on CONDFANB when any compressor is on.
Stage up occurs if SCTA > HPSP or OAT > 75
Stage up occurs if SCTB > HPSP or OAT > 75
g
OAT < 73
g
OAT < 73
If the SCTA sensor has failed, then the control defaults to control based on the OAT sensor and turns on CONDFANA when
the ambient is above 65 dF and off when the ambient temperature is below 50 dF. If the SCTA and OAT sensors have all
failed then the control turns on CONDFANA when any compressor is on.
MM
1
2
MM
1
4
MM
2
3
4
MM
1
MM
2
3
6
5
MM
3
MM
1
2
4
Fig. 9 — Outdoor Fan Staging Sequence for Factory-Installed Motormaster Option Units
Summary of Contents for WEATHERMAKER 48A2020
Page 112: ...112 Fig 20 Typical Main Control Box Wiring Schematic 48 50A Units ...
Page 113: ...113 Fig 21 Typical Auxiliary Control Box Wiring Schematic ...
Page 114: ...114 Fig 22 Typical 2 Stage Gas Heat Wiring Schematic Size 060 Units Shown ...
Page 115: ...115 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown TO NEXT PAGE ...
Page 116: ...116 Fig 23 Typical Staged Gas Heat Wiring Schematic Size 060 Units Shown cont ...
Page 117: ...117 Fig 24 Typical Electric Heat Control Schematic 50 Series Size 060 Units Shown ...
Page 118: ...118 Fig 25 Typical Controls Option Wiring Schematic SW1 SW2 OR DEHUMIDIFY SWITCH ...
Page 119: ...119 Fig 26 Typical Power Schematic 48 50A2 A3 A4 A5 060 Unit Shown ...
Page 120: ...120 Fig 27 Typical Power Schematic of Greenspeed Low Ambient Option 48 50A 060 Unit Shown ...
Page 121: ...121 Fig 28 Typical Small Chassis Component Location Size 020 035 Units ...
Page 122: ...122 Fig 29 Typical Large Chassis Component Locations Size 040 060 Units ...
Page 185: ...185 APPENDIX C VFD INFORMATION cont Fig F Internal Enclosure Fan Replacement A48 7716 ...