4. Installation
4.1 Installing module
SERVICE
D+ D− GND
GND
+ VIN −
+ CH1 −
+ CH2 −
+ CH3 −
PURGE
6
7
8
5
4
2
1
3
Figure 2 HMM170 component board
1
Service port (temporary connection,
USB cable with Vaisala Insight
software)
2
Digital RS-485 (Modbus) port
3
LED indicator
4
Grounding point
5
Mounting holes in the shaded area
match the mounting holes on HMM100
humidity module
6
Power input (12 ... 35 V DC
or
24 V AC ±10 %)
7
Active analog outputs (0/4 ... 20 mA,
1 ... 5 V, 0 ... 5/10 V)
8
External purge trigger (closing
activates purge)
1) Condensation prevention and chemical
purge features require at least 18 V DC.
Make sure that you prepare and connect only de-energized wires.
WARNING!
Electrostatic Discharge (ESD) can cause immediate or latent
damage to electronic circuits. Avoid touching exposed component contacts
during installation and maintenance.
CAUTION!
1. The module is delivered with a set of standoffs. Select the mounting holes you will be
using, and attach standoffs to the corresponding locations on the installation surface.
Always use the mounting hole marked
GND
as that is the grounding point for the module.
You may use other applicable standoffs that provide a minimum installation height of
6 mm (0.24 in).
2. Attach the module securely.
3. Make sure that the module has a good earth connection from the grounding point.
4. Connect wiring to the power input and signal output terminals.
5. Optional: connect wiring to the external purge trigger terminals.
HMM170 User Guide
M212259EN-D
16