Trane Tracer ZN517 - Page 46

Chapter 5 Applications for the 4-cool configuration
34 CNT-SVX12C-EN
For the CO
2
measurement configuration, a 4–20 mA sensor must be hard-
wired to the AI1 terminal as shown in Figure 11 on page 34. The sensor
will transmit a 0–2000 ppm value to the BAS. This configuration has no
direct effect on Tracer ZN517 operation. If a valid value is established
and then is no longer present, the controller generates a CO
2
Sensor Fail-
ure diagnostic.
Figure 11. AI1 terminal wiring: CO
2
measurement
For the RH measurement configuration, a hard-wired 4–20 mA zone
humidity sensor (see Figure 12) must provide a value to the controller. If
a valid hard-wired or communicated relative humidity value is estab-
lished and then is no longer present, the controller generates an RH Sen-
sor Failure diagnostic and disables the dehumidification function. The
RH sensor is used only to provide a valid humidity reading to a BAS; it
does not affect the operation of the Tracer ZN517.
Figure 12. AI1 terminal wiring: RH measurement
{{
+20GND
AI1
Tracer ZN517
24 Vac
CO
2
sensor
(Trane part number:
4190 4100 or 4190 4101)
+
–
+20GND
AI1
Tracer ZN517
RH sensor
Figure Note:
T
he +20 terminal provides 20 ±2 Vdc that is used to power a Trane RH sensor (part
numbers 4190 1109, 4190 7011, 4190 7012, 4190 7014).
GND
Out
24 Vac