12
Unit Operation
1
2
4
5
6
7
3
Analog Inputs
The ZN510 controller has five
available analog inputs (AI). These
inputs are factory-configured for the
following functions:
z
Zone = Space temperature.
z
Set = Local setpoint.
z
Fan = Fan mode input.
z
AI 1 = Leaving water tem-
perature (Circuit 1).
z
AI 2 = Discharge air tem-
perature.
See
Figure 8
for analog inputs.
Figure 7: High and low pressure switch
Note:
The ZN510 controller includes an automatic diag-
nostic reset function that allows the controller to
automatically recover after a high or low pres-
sure cutout
diagnostic. After 30 minutes the con-
troller will reset the diagnostics. Most
diagnostics occur due to intermittent water tem-
perature or flow problem. The “smart reset” may
eliminate many service calls.
J3-4
AI
2
J3-3
J3-2
AI
1
J3-1
TB3
-5
TB3
-4
TB3
-3
TB3
-2
TB3
-1
Discharge Air
Sensor
Leaving Water
Sensor (Circuit)
Z
one
Se
tp
oin
t
Fa
n
An
al
og
I
n
put
s
Zone Sensor
Figure 8: Analog inputs.
(1
TB
1-
1
)
Gr
ou
nd
(1
TB
1-
2
)
(1
TB
1-
3
)
(1
TB
1-
4
)
Binary Outputs
24 VAC
HPC
LPC
Compr 2
Compr 1
