Teledyne GFC-7000T - Trace CO2 Analyzer - manual - Manual (Page 132)

Operating Instructions Model GFC7000TA Carbon Dioxide Analyzer
Teledyne Analytical Instruments 114
6.11.7. Multidrop RS-232 Set Up
The RS-232 multidrop consists of a printed circuit assembly that is seated on the analyzer’s CPU card
(see Figures 6-10 and 6-13) and is connected to the CPU and the motherboard. This PCA includes all
circuitry required to enable your analyzer for multidrop operation. It converts the instrument’s RS232 port
to multidrop configuration allowing up to eight analyzers to be connected the same I/O port of the host
computer.
Because both of the DB9 connectors on the analyzer’s back panel are needed to construct the multidrop
chain, COM2 is no longer available for separate RS-232 or RS-485 operation; however, the USB com
port is available.
Figure 6-9: Multidrop/LVDS PCA Seated on CPU
Each analyzer in the multidrop chain must have:
 One Teledyne Instruments option 62 installed.
 One 6’ straight-through, DB9 male  DB9 Female cable (Teledyne Instruments P/N WR0000101) is
required for each analyzer.
To set up the network, for each analyzer:
1. With NO power to the instrument, open the rear panel and locate the CPU.
2. On the LVDS card, disconnect the cable that’s connected to J1 and remove the LVDS card from
the CPU card.
3. Mount the Multidrop/LVDS card onto the CPU and reconnect the LVDS cable to J1.