Teledyne MODEL T703 7.3. MULTIDROP RS-232 SET UP

Operating The T703 over the Serial I/O Ports Teledyne API T703 Calibrator Operation Manual
118
7.3. MULTIDROP RS-232 SET UP
When the RS-232 Multidrop option is installed, the instrument designated as last in the chain must be
terminated. This requires installing a shunt between two pins on the multidrop printed circuit assembly (PCA)
inside the instrument. Step-by-step instructions follow.
Note that because the RS-232 Multidrop option uses both the RS232 and COM2 DB9 connectors on the
analyzer’s rear panel to connect the chain of instruments, COM2 port is no longer available for separate RS-232
or RS-485 operation.
To install shunt in the last analyzer:
1. With NO power to the instrument, remove its top cover and lay the rear panel open for access to the
multidrop PCA, which is seated on the CPU.
2. On the multidrop PCAs JP2 connector, use the shunt provided to jumper Pins 21  22 as indicated in
Figure 7-3.
Figure 7-3: Multidrop/LVDS PCA Seated on CPU
CAUTION – Risk of Instrument Damage and Warranty Invalidation
Printed circuit assemblies (PCAs) are sensitive to electro-static discharges too
small to be felt by the human nervous system. Damage resulting from failure to use
ESD protection when working with electronic assemblies will void the instrument
warranty.
See A Primer on Electro-Static Discharge section in this manual for more information on
preventing ESD damage.
07223B DCN6378