York J Series - Table 11 - Humidity Sensor Output; Table 12 - Co Sensor Output

FORM 100.50-NOM7 (808)
73
JOHNSON CONTROLS
6
CO
2
Sensor
The CO
2
sensor is used in conjunction with the Demand
Ventilation option. The demand for ventilation is deter-
mined by comparing the level of CO
2
in the building
to the Demand Ventilation Setpoint. The CO
2
level in
the building is measured by the CO
2
sensor and outputs
0 to 10 volts DC based on the level of carbon dioxide
sensed. The unit controller then modulates the outside
air dampers to bring the level of CO
2
. Table 12 illustrates
the DC output for a given CO
2
level.
CO
2
OUTPUT TABLE
PPM CO
2
OUTPUT VOLTAGE - VDC PPM CO
2
OUTPUT VOLTAGE - VDC
200 0.40 2800 5.60
400 0.80 3000 6.00
600 1.20 3200 6.40
800 1.60 3400 6.80
1000 2.00 3600 7.20
1200 2.40 3800 7.60
1400 2.80 4000 8.00
1600 3.20 4200 8.40
1800 3.60 4400 8.80
2000 4.00 4600 9.20
2200 4.40 4800 9.60
2400 4.80 5000 10.00
2600 5.20
TABLE 12 – CO
2
SENSOR OUTPUT
Humidity Temperature Sensor – Outside, Return
and UnderFloor (MIT)
The humidity/temperature sensor is a combination sen-
sor that will output a 0 to 5 volt DC voltage in response
to a the relative humidity sensed. The humidity sensor
is used in conjunction with the economizer function.
The combination sensor also has a temperature sensor
that senses the outdoor air temperature and has the same
TABLE 11 – HUMIDITY SENSOR OUTPUT
HUMIDITY SENSOR OUTPUT TABLE
% RELATIVE HUMIDITY OUTPUT VOLTAGE - VDC % RELATIVE HUMIDITY OUTPUT VOLTAGE - VDC
5 0.25 55 2.75
10 0.50 60 3.00
15 0.75 65 3.25
20 1.00 70 3.50
25 1.25 75 3.75
30 1.50 80 4.00
35 1.75 85 4.25
40 2.00 90 4.50
45 2.25 95 4.75
50 2.50 100 5.00
resistance value of a “stand-alone” outdoor sensor. The
resistance value for a specic outdoor temperature is
shown in Table 8. Note that the combination humid-
ity/temperature sensor has four terminals – two for the
humidity sensor and two for the temperature sensor.