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Designs, materials, weights and performance ratings are approximate and subject to change without notice. Visit
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37
Communications
Wire to the RS-485 pin header seen below:
Pin 1 – RS -
Pin 2 – RS +
Pin 3 – GND
Make sure all other connections are made properly.
Refer to the Control Wiring Section of this IOM.
1. Power on the unit by the front panel On/Off switch.
2. Enter Menu 234.
3. Scroll down to “Control Sgnal In”. If you want to control the unit
through Modbus change this to “ Digital Ctrl “. If you want to
only monitor the EHU-800 using a local humidistat / controller or
sensor, select the appropriate setting for you.
4. Scroll down to “Identification of EHU”. Default is set at “1”. This
sets the address of the EHU-800 between
1 and 80.
5. Scroll to “Speed Data”. The default baud rate is 9600. Adjust this
to match your system.
Changes to the unit can now be done through the Building
Management System or through the keypad at the EHU-800.
Refer to the Modbus Variants List to set up the required
points.
