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112
Table 110 — Controls Expansion Board (CEM) Inputs
SCROLLING MARQUEE — This device is the keypad in-
terface used to access the control information, read sensor
values, and test the unit. The Scrolling Marquee display is a
4-key, 4-character, 16-segment LED display as well as an
Alarm Status LED. See Fig. 26. The display is easy to operate
using 4 buttons and a group of 11 LED’s that indicate the
following menu structures:
• Run Status
• Service Test
• Temperatures
• Pressures
• Set points
• Inputs
• Outputs
• Configuration
• Timeclock
• Operating Modes
• Alarms
Through the Scrolling Marquee the user can access all the
inputs and outputs to check on their values and status. Because
the unit is equipped with suction pressure transducers and
discharge saturation temperature sensors it can also display
pressures typically obtained from gages. The control includes a
full alarm history, which can be accessed from the display. In
addition, through the Scrolling Marquee the user can access a
built-in test routine that can be used at start-up commission and
to diagnose operational problems with the unit. The Scrolling
Marquee is located in the main control box and is standard on
all units.
SUPPLY FAN — The size 020 to 050 units are equipped with
two 15 x 11-in. forward-curved fans. The size 051 and 060
units have three 15 x 11-in. fans. They are on a common shaft
and are driven by single belt drive 3-phase motor. The fan is
controlled directly by the
Comfort
Link™
controls.
VARIABLE FREQUENCY DRIVE (VFD) — On variable
volume units, the supply fan speed is controlled by a 3-phase
VFD. The VFD is located in the fan section behind a remov-
able panel as shown in Fig. 20 and 21. The VFD speed is
controlled directly by the
Comfort
Link controls through a 4 to
20 mA signal based on a supply duct pressure sensor. The
inverter has a display, which can be used for service diagnos-
tics, but setup of the supply duct pressure set point and control
loop factors is done through the Scrolling Marquee display.
The VFD is powered during normal operation to prevent
condensation from forming on the boards during the off mode
and is stopped by driving the speed to 0 (by sending a 2 mA
signal to the VFD).
The A series units use ABB ACH550 VFDs on all 230-3-60
and 460-3-60 units. An ABB ACS800 or Toshiba E3 VFD
is used on 575-3-60 units. The interface wiring for the
VFDs is shown in Fig. 27. Terminal designations are shown in
Table 112.
Table 111 — IGC Board Inputs and Outputs
POINT
NAME
POINT DESCRIPTION
I/O POINT
NAME
PLUG AND PIN
REFERENCE
SIGNAL PIN(S)
PORT STATE
INPUTS
SFS
Supply Fan Status switch
DI 1
J7, 1-2
2
0 = 24vac, 1= 0vac
DMD_SW1
Demand Limit - Redline
DI 2
J7, 3-4
4
0 = 24vac, 1= 0vac
DMD_SW2/
DHD ISCIN
Demand Limit - Load Shed/
Dehumidity Switch Input
DI 3
J7, 5-6
6
0 = 24vac, 1= 0vac
PRES
Pressurization
DI 4
J7, 7-8
8
0 = 24vac, 1= 0vac
EVAC
Evacuation
DI 5
J7, 9-10
10
0 = 24vac, 1= 0vac
PURG
Purge
DI 6
J7, 11-12
12
0 = 24vac, 1= 0vac
IAQIN
Indoor Air Quality Switch
DI 7
J7, 13-14
14
0 = 24vac, 1= 0vac
AN7
J6, 1-3
2 (1 = loop power)
(0-20mA input)
DMDLMTMA
4-20mA Demand Limit
AN8
J6, 4-6
5 (4 = loop power)
(0-20mA input)
EDTRESMA
4-20mA Evaporator Discharge SP Reset
AN9
J6, 7-9
8 (7 = loop power)
(0-20mA input)
OAQ
Outside Air CO
2
Sensor
AN10
J6, 10-12
11 (10 = loop power)
(0-20mA input)
SPRESET
SP Reset milliamps
AN10
J6, 10-12
11 (10 = loop power)
(0-20mA input)
CEM_10K1/
CEM_4201
CEM AN1 10k temp J5,1-2/
CEM AN1 4-20 ma J5,1-2
AN1
J5, 1-2
1
(thermistor, ohms)
CEM_10K2/
CEM_4202
CEM AN2 10k temp J5,3-4/
CEM AN2 4-20 ma J5,3-4
AN2
J5, 3-4
3
(thermistor, ohms)
CEM_10K3/
CEM_4203
CEM AN3 10k temp J5,5-6/
CEM AN3 4-20 ma J5,5-6
AN3
J5, 5-6
5
(thermistor, ohms)
CEM_10K4/
CEM_4204
CEM AN4 10k temp J5,7-8/
CEM AN4 4-20 ma J5,7-8
AN4
J5, 7-8
7
(thermistor, ohms)
AN5
J5, 9-10
9
(thermistor, ohms)
AN6
J5, 11-12
11
(thermistor, ohms)
POINT NAME
POINT DESCRIPTION
CONNECTOR
PIN NO.
INPUTS
RT
24 Volt Power Supply
R1,C
W
Heat Demand
2
G
Fan
3
LS
Limit Switch
7,8
RS
Rollout Switch
5,6
SS
Hall Effect Sensor
1,2,3
CS
Centrifugal Switch (Not Used)
9,10
FS
Flame Sense
FS
OUTPUTS
CM
Induced Draft Motor
CM
IFO
Indoor Fan
IFO
R
24 Volt Power Output (Not Used)
R
SPARK
Sparker
—
LED
Display LED
Run Status
Service Test
Temperature
Pressures
Setpoints
Inputs
Outputs
Configuration
Time Clock
Operating Modes
Alarms
Alarm Status
ENTER
MODE
ESCAPE
Fig. 26 — Scrolling Marquee
A30-2239
Summary of Contents for WEATHERMAKER 48AJ020
Page 95: ...95 Fig 13 Typical Main Control Box Wiring Schematic A48 7787 ...
Page 96: ...96 TO NEXT PAGE Fig 14 Auxiliary Control Box Wiring Schematic A48 7294 ...
Page 98: ...98 Fig 15 Typical 2 Stage Gas Heat Wiring Schematic Size 051 and 060 Units Shown A48 6866 ...
Page 102: ...102 TO NEXT PAGE Fig 18 Typical Power Schematic Size 051 and 060 Units Shown A48 7298 ...
Page 104: ...104 Fig 19 Controls Option Wiring Schematic A48 7810 ...
Page 105: ...105 Fig 20 Small Chassis Component Location Size 020 035 Units A48 7301 ...
Page 106: ...106 Fig 21 Large Chassis Component Locations Size 036 060 Units A48 7302 ...