Vaisala HMDW110 - Installation; Selecting Installation Location; HMD110;112 Installation Procedures

You can pull out the terminal blocks from the component board for easier
installation, and to disconnect the transmitter from power and RS-485 when using
the service port.
Before using the transmitter in Modbus mode, always disconnect the terminal
block for terminals 5 ... 8 to prevent the eects of ground loop on measurements.
The RS-485 connector used for Modbus communication in the lower terminal
block will power the transmitter.
2.7 Analog Output Overrange Behavior
Analog outputs of the HMDW100 series transmitters have a defined behavior when the values
measured by the transmitter are outside the scaled analog output range:
• Output is clipped at the end of the scaled output range.
• You can allow the output exceed the scaled range by 10% with the aover serial
command.
• Output is set to error state (default 3.6 mA) if an error is active (for example, due to
sensor damage). You can change the error state using the aerr command.
For configuration of the analog outputs using serial commands, see Analog Output (page 46).
2.8
Safety
The Vaisala HMDW110 series transmitter delivered to you has been tested for safety and
approved as shipped from the factory. Note the following precautions:
Do not modify the unit or use it in ways not described in the
documentation. Improper modification may lead to safety hazards, equipment
damage, failure to perform according to specification, or decreased equipment
lifetime.
CAUTION!
2.8.1 ESD Protection
Electrostatic Discharge (ESD) can damage electronic circuits. Vaisala products are adequately
protected against ESD for their intended use. However, it is possible to damage the product by
delivering electrostatic discharges when touching, removing, or inserting any objects in the
equipment housing.
To avoid delivering high static voltages to the product:
• Handle ESD-sensitive components on a properly grounded and protected ESD workbench
or by grounding yourself to the equipment chassis with a wrist strap and a resistive
connection cord.
HMDW110 User Guide M211726EN-D
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