24
4.5.
Supply Static Pressure Sensor - Optional
The supply duct differential static pressure sensor (A30) is an analog sensor with a 0-10VDC output over a range of
0-5"w.c as shown in the following table. The sensor is powered with 24VAC.
Table 15. Static Pressure
Pressure "w.c.
DC Voltage
Pressure "w.c.
DC Voltage
Pressure "w.c.
DC Voltage
Pressure "w.c.
DC Voltage
0
0
1.5
3
3
6
4.5
9
0.5
1
2
4
3.5
7
5
10
1
2
2.5
5
4
8
4.6.
Enthalpy Sensor - Optional
The optional enthalpy sensors (A7 and A63) used with the economizer have an output of 4-20mA. The sensor is powered
with 18VAC provided by M3 unit controller (see figure 9 on page 48).
4.7.
Economizer Differential Pressure Sensor - Optional
Rooftop units installed with Smart Airflow™ will have a Pressure Transducer (PT5) present in the economizer. PT5
requires 5VDC power supply (P266-5 and {P266-6) and gives 0.25 VDC to 4 VDC output (P266-4) corresponding to 0”
water column and 2” water column respectively. For all practical purposes the output should be less than 1.2” water
column if not an error code is stored and service alarm output is turned on.
