Programming instructions

56 Designer’s Guide
Calsense
• A maximum of 12 controllers using FLOWSENSE technology in a single chain
Hardwire Line Amplifier (model LA-2 PC)
The Calsense line amplifier (model LA-2 PC) allows communication directly from a central computer to
hardwire controllers in the field without the need for an additional central communication device. This
device connects to an RS-232 serial port on the computer and is wired directly to the Paige P7171D cable
in the field (Figure 32
).
Note: If connecting an LA-2 PC to a FLOWSENSE chain, the controller it connects to must have a
dedicated -M option used for central traffic. This means the controller has to be specified either as -M-M
if using hardwire for FLOWSENSE traffic, or -M-SR if using spread spectrum radio.
Figure 32 - LA-2 PC Line Amplifier
Sharing a Central Communication Option with FLOWSENSE chains
With properly designed FLOWSENSE chains, sites with multiple chains can share a single central
communication option. This is accomplished by using either hardwire (model -M) or spread spectrum
radio (model -SR) controllers to bridge from one FLOWSENSE chain to other chains or non-
FLOWSENSE controllers.
There are three such scenarios:
• Bridging Chains using -M-M Controllers
• Bridging Chains using -M-SR Controllers
• Bridging Chains using a -SR Hub
LA-2 PC Line
Amplifier
Computer with
Calsense Command Center
Calsense
controller
with -M
option
Paige P7171D
communication cable