User Manual

GML20T LonWorks
®
module
1
MOUNTING AND INSTALLATION
The GML20T LonWorks
®
interface module enables communication between a
LonWorks
®
network and a GMW21 transmitter over a twisted pair. The carbon dioxide is
measured by a GMW21 transmitter and the temperature by the GML20T module itself.
1. Open the transmitter cover and remove the jumper from the pin connector at the
center of the circuit board.
2. Pull the two network wires through the hole at the bottom of the housing. When
connecting them to the screw terminal marked 'NET' of the GML20T, hold the module
in one hand and make connections with the other (see Figure 1). The polarity can be
freely selected. Note that as all NDIR transmitters consume power, an additional
power supply is always needed. Check that the nominal 24 V supply is connected
between terminals + and - on the transmitter's mother board. Analogue output signals
can be used simultaneously with the LonWorks
®
module.
Figure 1: Hold the module in hand while connecting the wires
3. Install the module on the 2- and 5-pin connectors as indicated in Figure 2. Make sure
that the wires are between the module and the transmitter board before pressing the
module in place.
Figure 2: Installing the GML20T module