3 Installation

Model 3020T

 

 

 

 

 

 

 

 

 

The range in use (HI, MED, LO)

The span of the range (0-100 ppm, etc)

Which alarms—if any—are disabled (AL–x DISABLED)

Which alarms—if any—are tripped (AL–x ON).

Each status output is followed by a carriage return and line feed.

Three input functions using RS-232 have been implemented to date. They are described in Table 3-4.

 

Table 3-4: Commands via RS-232 Input

Command

Description

as<enter>

Immediately starts an autospan.

az<enter>

Immediately starts an autozero.

st<enter>

Toggling input. Stops/Starts any status message output from

 

the RS-232, until st<enter> is sent again.

The RS-232 protocol allows some flexibility in its implementation. Table 3-5 lists certain RS-232 values that are required by the 3020T imple- mentation.

Table 3-5: Required RS-232 Options

Parameter

Setting

Baud

2400

Byte

8 bits

Parity

none

Stop Bits

1

Message Interval

2 seconds

3.3.9 Remote Sensor and Solenoid Valves

The 3020T is a single-chassis instrument, which has its own sensor and, in the –C option, its own gas-control solenoid valves. The REMOTE SEN- SOR connector is not used, and the SOLENOID RETURN connectors are used (without the –C option) to synchronize external gas control valves, if desired. See Figure 3-7.

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Teledyne Analytical Instruments

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Teledyne 3020T operating instructions Command Description, Parameter Setting, Remote Sensor and Solenoid Valves