Omega Engineering Dissolved Oxygen System Oxygen Equipment User Manual


 
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4.6 Analog Outputs
4.6.1 The analog output signals consist of a non-isolated 0-1 mA, 0-5 Vdc, and isolated 4-
20 mA signals.
4.6.2 From the factory all of the analog outputs have a linear range corresponding to the
full range of the instrument. The 4-20 mA output can be programmed to another
linear range by entering two values:
• Output High: This is the D.O. value at which you wish to have 100% output.
• Output Low: This is the D.O. value at which you wish to have 0% output.
4.6.3 When programming, you must ensure that the output range has a span of at least
10% of the full range of the instrument. For applications that require the output to
decrease as the process value increases, i.e. an inverted output, the Output High
value will be less than the Output Low. See Section 5.4.
4.6.4 The instrument may be used to measure the temperature of the process either in
Celsius or in Fahrenheit. The DOCN600 does not control temperature but the 0-5
Vdc and 0-1 mA analog outputs can be dedicated to follow the process
temperature. See Sections 5.6.
4.7 Operation Menu
4.7.1 The operation menu allows the user to recall and to adjust the parameters, required
by the analyzer functions.
4.7.2 When the analyzer is powered up, the program will display D.O. readings. None of
the LEDs in the operation menu will be illuminated.
4.7.3 Five buttons on the panel are used to operate the menu. Use the CALL button to
step through the items in the menu, one at a time. The red LEDs beside each item
makes it very easy to follow the menu. The function of the RUN button is to return
to the on-line D.O. display from anywhere in the menu. The analyzer has a built-in
timer which, when enabled, by DIP Switch 7 Bank S1 (Section 4.8), returns the
program to RUN mode if no button has been pressed for 10 minutes. This time-out
has the same effect as pressing the RUN button.