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3-9
Multi-Channel Combustible Monitor
Installation 3
Teledyne Analytical Instruments
3.4.3 Adding or Removing the Second Sensor PCB
The model 1220 channel module may be configured for operation
with either one or two combustible sensors. Each sensor's power supply
resides on a sensor PCB. The location of the two sensor PCBs is shown in
Figure 3-4. The single sensor PCB is factory installed at location SEN-
SOR 1. In order to use two sensors with a single channel module, an
additional sensor PCB must be installed at location SENSOR 2.
To add or remove the SENSOR 2 PCB, first remove the channel
module cover as in section 3.4.1 and add/remove the second sensor PCB as
shown in Figure 3-4.
3.4.4 Configuring the Internal Jumper Connections
The Channel Module outputs may be configured by setting the inter-
nal jumpers. In addition there are several factory preset jumpers config-
ured as shown in the following table. Changing the internal jumpers re-
quires removing the channel module cover as in section 3.4.1.
The Channel Module is configured to provide an RS485 communica-
tion link with the Control Unit (not available at this time). This communi-
cation link is not compatible with Control Units having the Common
Meter. In order to use the Channel Module with a Control Unit that has a
Common Meter, remove jumpers JP1 and JP3 as indicated in the follow-
ing table: