When using the RDP100 with HMDW110 series transmitters, do not connect the
Extpwr jumper to the RDP100 component board.
3.6 Wiring Devices With Modbus Output
Use terminals 1 ... 4 for supply power and Modbus output. In addition to RS-485 data wires, the
common wire (ground reference) must be connected between the RS-485 host and the
HMDW110 transmitter.
DC power supply
-
+
4 Pwr+
3 Pwr-
2 RS485-
1 RS485+
RS-485 host
RS-485 +
RS-485 -
RS-485 common
Figure 12 HMDW110 Wiring, Modbus Output
Do not connect the analog outputs (terminals 5 ... 8) at the same time when
supply power and/or Modbus output is connected to terminals 1 ... 4. Having both
terminals connected simultaneously may result in erroneous analog readings
caused by effects of possible ground loop.
Chapter 3 – Installation
27
Summary of Contents for hmdw110 series
Page 1: ...M211726EN D User Guide Vaisala Humidity and Temperature Transmitter Series HMDW110 ...
Page 5: ...Recycling 87 Table of Contents 3 ...
Page 87: ...Appendix A Modbus Reference 85 ...
Page 88: ...HMDW110 User Guide M211726EN D 86 ...
Page 90: ...HMDW110 User Guide M211726EN D 88 ...
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