Trace Oxygen Analyzer Installation
Teledyne Analytical Instruments 13
The RS-232 protocol allows some flexibility in implementation in
the choice of values for certain parameters. Table 3-2 lists the RS-232
values required by the Model 3300ZB implementation.
Table 3-2: Required RS-232 Options
Parameter Setting
Baud 2400
Byte 8 bits
Parity none
Stop Bits 1
Message Rate 2 per second
3.4 Gas Connections
The standard Model 3300ZB has two inlet (sample and span) and
one outlet port. All connections have 1/8” tube fittings installed. A
switching valve is provided to feed the unit with either sample or
calibration gas as shown in Figure 3-3.
A flowmeter and flow controller valve are part of the system and
will assist in setting the flow of the gas.
Sample flow should be adjusted to 2 SCFH. The sample vent
connection should not restrict the sample flow. The sensor is designed to
operate at atmospheric pressure. Restricting the sample vent line will
result in pressurizing the sensor and altering the O2 reading.
The pressure required will depend on the sampling system. When
venting into a constant pressure, such as the atmosphere, controlling
input pressure is simple. If you are venting into a system of varying
pressure, then some form of pressure regulation is required to maintain a
constant pressure.
Sample and span pressure must NOT exceed 50 psig (345 Kpa).
Figure 3-3 shows a standard piping diagram for positive pressure
service.