Vaisala HMT330 - Manual (Page 131)

Chapter 4 _________________________________________________________________ Operation
VAISALA _______________________________________________________________________ 129
Table 31 Relay State Examples
Criterion for
Relay Activation
Transmitter
Operation Status
NC-C
Connected
NO-C
Connected
Not chosen
Power off
RH below 50 %*
Measured RH
above 50 %
Measured RH
below 50 %
RH above 50 %*
Measured RH
above 50 %
Measured RH
below 50 %
Fault status
Measurement OK
Error active
Online status
Measurement live
Purge or sensor
heating active
* Hysteresis has an effect when relay switching is based on live measurement.
See section Hysteresis on page 127.
Enabling/Disabling Relays
You can deactivate the relay outputs for example for service purposes of
your system.
Setting Relay Outputs
NOTE When you have only one relay module installed, its relays are called
“relay 1” and “relay 2”.
When you have two relay modules, the relays of the module connected
to slot MODULE 1 are called “relay 1” and “relay 2” and relays
connected to slot MODULE 2 are called “relay 3” and “relay 4”.