Teledyne Analytical Instruments 3000PA-EU, Руководство по эксплуатации

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3 Installation 3 Installation
3 Installation 3 Installation
3 Installation Model 3000PA
3-10
Teledyne Analytical Instruments
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.
Figure 3-6: FET Series Resistance
3.3.2.3 RS-232 Port: The digital signal output is a standard RS-232
serial communications port used to connect the analyzer to a computer,
terminal, or other digital device. It requires a standard 9-pin D connector.
The data is status information, in digital form, updated every two
seconds. Status is reported in the following order:
• The concentration in percent
• The range in use (HI, MED, LO)
• The span of the range (0-10 %, 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.
Four input functions using RS-232 have been implemented to date.
They are described in Table 3-1.
Table 3-1: Commands via RS-232 Input
Command Description
as<enter> Immediately starts an autospan.
az<enter> Immediately starts an autozero.
co<enter> Reports "Raw Cell Output" (current output of the sensor
itself) in
µ
A. For example—
Raw Cell Output: 99
µ
A
.