Figure 3-4: Remote Valve Connections - Teledyne 2120XL Operating Instructions Manual

Trace Nitrogen in Argon Analyzer
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Network I/O: A 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. Pins 13 (+) and 29 (–).
Remote Valve Connections: The Model 2120XL is a single-chassis
instrument and does not have a Remote Probe. Instead, the Remote
Probe connections are used as a method for directly controlling external
sample/zero/span gas valves. See Figure 3-4.

Figure 3-4: Remote Valve 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 3-5.
Teledyne Analytical Instruments
Range 3 ID Contact
Range 4 ID Contact (not used)
Range 4 ID Contact (not used)
Installation
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