Teledyne 3000ZA-3X - Trace oxygen analyzer - Manual (Page 35)

Trace Oxygen Analyzer Installation
Teledyne Analytical Instruments 23
Network I/O: Pins 13 (+) and 29 (–) are for serial digital input/output
for local network protocol. At this printing, this port is not yet
functional. It is to be used for future options to the instrument.
Remote Valve Connections: The 3000ZA is a single-chassis
instrument, which has no Remote Valve Unit. Instead, the Remote Valve
connections are used as a method for directly controlling external
sample/zero/span gas valves. See Figure 3-5.
Figure 3-5: Remote Probe Connections
The voltage from these outputs is nominally 0 V for the OFF and
15 VDC for the ON conditions. The maximum combined current that
can be pulled from these output lines is 100 mA. (If two lines are ON at
the same time, each must be limited to 50 mA, etc.) If more current
and/or a different voltage is required, use a relay, power amplifier, or
other matching circuitry to provide the actual driving current.
In addition, each individual line has a series FET with a nominal
ON resistance of 5 ohms (9 ohms worst case). This can limit the
obtainable voltage, depending on the load impedance applied. See
Figure 3-6.