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51
2-1/64 (55)
51/64 (21)
4-1/4 (108)
2-3/4 (70)
NOTE
: Dimensions in ( ) are in mm
C12036
Fig. 61 -- Enthalpy Control Sensor, Dimensions and
DIP Switch Location
Table 15 – Enthalpy Control Sensor
Wiring Terminations
a
Terminal
Type
Description
Nbr
Label
1
S---BUS
S---BUS
S---Bus Communications
(Enthalpy Control Sensor Bus)
2
S---BUS
S---BUS
S---Bus Communications
(Enthalpy Control Sensor Bus)
a Terminals are polarity insensitive.
Table 16 – Enthalpy Control Sensor DIP Switch Settings
Use
DIP Switch Positions for Switches 1, 2, & 3
1
2
3
DA
a
OFF
ON
OFF
RA
b
ON
OFF
OFF
OA
c
OFF
OFF
OFF
a DA = Discharge Air
b RA = Return Air
c OA = Outside Air
When a S--bus sensor is connected to an existing network,
it will take 60 minutes for the network to recognize and
auto--configure itself to use the new sensor. During the 60
minute setup period, no alarms for sensor failures (except
SAT) will be issued and no economizing function will be
available.
Operating Sequences
Staged Air Volume (3--Speed) Fan Motor —
The Integrated Staging Control (ISC) Board in the main
unit
determines
the
operating
speed
(LOW/MED/HIGH) of the indoor fan based on space
thermostat demand conditions. See Table 17 for this
logic.
Table 17 – Supply Fan Speed Logic without Economizer
TSTAT
OUTPUT
G/OCC
0---V
24---V
0---V
0---V
Y1
0---V
24---V
0---V
0---V
Y2
0---V
0---V
24---V
0---V
Y3
0---V
0---V
0---V
24---V
W1
0---V
0---V
0---V
24---V
W2
0---V
0---V
0---V
24---V
SUPPLY
FAN
MOTOR
SPEED
OFF
LOW
MED
HIGH
W7220 Economizer Control —
Tables 18 and 19 provide the W7220 Input/Output Logic.
Table 18 describes economizer functions for a unit
without a CO
2
sensor. Table 19 describes economizer
functions for a unit with Demand Control Ventilation
(CO
2
sensor connected). The supply fan speed is included
in these tables for reference; this is neither an input or
output of the W7220 controller.
Base Unit Controls —
Base unit includes standard electromechanical controls,
Staged Air Volume (3--speed supply fan motor with VFD),
EconoMi$er X (with W7220 controller) and thermostat or
unitary controller that energizes the G terminal in cooling
and heating to control the supply fan operation.
Cooling, Unit With EconoMi$er X Without CO
2
—
For Occupied mode operation of EconoMi$er X, there
must be a 24--v signal at terminal G at the unit’s
Integrated Staging Control Board from the thermostat;
supply fan motor will start and run in Low Speed. The
signal at G is connected to W7220 input OCC, placing the
EconoMi$er X control in Occupied mode; the economizer
actuator is commanded open to the MIN POS L
ventilation position. Removing the signal at OCC places
the EconoMi$er X control in Unoccupied mode; the
economizer actuator is driven back to full--closed position.
When free cooling using outside air is not available, the
unit cooling sequence will be controlled directly by the
space thermostat. Thermostat call for Stage 1 Cooling
energizes ISC terminals G and Y1; supply fan motor starts
and runs in Low Speed. The Y1 demand is received at
W7220 terminal Y1--I. Outside air damper position will be
at MIN POS L. W7220 output Y1--O is energized; first
stage mechanical cooling starts.
As space temperature falls and space cooling load is
satisfied, the thermostat will remove its call for first stage
cooling; ISC terminal Y1 call is removed. The W7220
input Y1--I is removed; output Y1--O is de--energized,
stopping first stage cooling.
When ISC terminal Y1 is de--energized, terminal G may
remain energized, indicating Continuous Fan operation.
The supply fan motor will continue to run in Low Speed.
Summary of Contents for 50LC 07
Page 9: ...9 COOLING CHARGING CHARTS C150169 Fig 9 Cooling Charging Charts 07 ...
Page 10: ...10 COOLING CHARGING CHARTS C150172 Fig 10 Cooling Charging Charts 08 ...
Page 11: ...11 COOLING CHARGING CHARTS C150170 Fig 11 Cooling Charging Charts 09 ...
Page 12: ...12 COOLING CHARGING CHARTS C150171 Fig 12 Cooling Charging Charts 12 ...
Page 27: ...27 C150181 Fig 34 50LC 07 Control Wiring Diagram ...
Page 28: ...28 C150225 Fig 35 50LC 07 RTU Open Control Wiring Diagram ...
Page 29: ...29 C14095 Fig 36 50LC 07 Power Wiring Diagram 208 230V 460V and 575V Units ...
Page 30: ...30 C14013 Fig 37 50LC 08 12 Control Wiring Diagram ...
Page 31: ...31 C14104 Fig 38 50LC 08 12 RTU Open Control Wiring Diagram ...
Page 32: ...32 C14105 Fig 39 50LC 08 12 Power Wiring Diagram 208 230V Units ...
Page 33: ...33 C150216 Fig 40 50LC 08 12 Power Wiring Diagram 460V 575V Units ...
Page 57: ...57 C13683 Fig 62 Typical EconoMi er X Wiring Diagram ...