Wiring - GMW83 - GMW83A - GMW83D - GMW83DRP - GMW83DRPC - GMW83RPC - GMW84 - GMW84S - GMW86P - GMW87M

GMW80 Series User Guide

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User guide
CAUTION With passive Pt1000 sensors the length of the cables affects the accuracy of the measurement reading, since the connection is susceptible to electrical interference. Vaisala recommends using shielded twisted pair cables, with the shield grounded. When using a shielded cable, do not connect the shield to the transmitter.

When connecting wiring, refer also to Transmitter parts.

Connect the wiring to the screw terminals on the mounting base. The terminal assignments are marked next to the screw terminals. Do not connect wiring to unmarked terminals.

Note that the analog signal ground terminal is internally connected to the power supply ground terminal.

Maximum wire size is 2 mm2 (AWG14). Route the cable through the hole in the mounting base if possible.
The GMW87 and GMW88 transmitters are wired either through a cable gland on the bottom of the transmitter or an alternative lead-through on the back of the transmitter. See GMW87 and GMW88 transmitter parts.
Figure 1. Routing the cable from behind (GMW83, GMW84, and GMW86 models)
WARNING Connect only de-energized wires.
CAUTION Do not route the cable through the area marked NO CABLES on the mounting base. That space is taken up by the CO2 measurement module when the transmitter cover is attached.

You can also bring the cable to the housing from above or below, but you have to break off the small plastic tab that covers the hole on top or bottom of the housing.

Figure 2. Locations of the breakaway tabs
When wiring from below, you can secure the cable with a cable tie to provide strain relief.
Figure 3. Wiring from below with cable tie strain relief

After completing the wiring, connect the transmitter body over the mounting base. Note that mounting bases are model-specific.