Omega Engineering Dissolved Oxygen System Oxygen Equipment User Manual


 
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e) Now proceed to turn each of the other S43 switches On with the remaining
switches Off.
The display should read within 5% of 25°C with Switch 2 On and 35°C with
Switch 3 On.
If this is the case the analyzer is in order and the problem is in the sensor.
Otherwise the problem is in the analyzer.
f) Return S40 and S41 to “On line” and ensure that all S43 switches are Off.
9.2 Escape
9.2.1 If the instrument appears to be "DEAD", for example not responding to the buttons,
or not performing on line measurement and control, always try the reset feature
first, as described in 6.3.1.
9.2.2 a) The "ESCAPE" procedure is to be used normally at the factory only, when the
unit is powered with a new MCU. As a result, the internal non-volatile memory
(EEPROM) is "FORMATTED" and the factory values are loaded into it.
b) The "ESCAPE" procedure is to be used if a unit is serviced for a new MCU
insertion, in case where the MCU was not calibrated at OMEGA, or in case of a
memory loss problem, when so advised by OMEGA service support.
9.2.3 Before performing the "ESCAPE" procedure it is important to know that this
procedure provides the option to erase all programmed values and replace them
with the factory set default values. This is also true for the control setpoints and
deadbands, then alarm settings and the analog outputs scaling. Also, the
temperature and the D.O. calibration points will be set to their initial values. This
means, that the temperature and the D.O. calibration must be performed after an
“ESCAPE” procedure. After that, all the control, alarm and scaling parameters
mentioned above must be set to the user values.
9.2.4 To perform the ""ESCAPE"" proceed as follows.
a) Turn off the power.
b) Press and hold the RUN button for about 3 seconds, while turning on the
power.
The FAIL LED will turn on and STATUS LED will become red and status code 7
will be obtained to show that the ESCAPE procedure was just performed.
9.2.5 After the "ESCAPE" procedure it is necessary to do the following:
a) Tune the analog outputs and the temperature output span to suit your particular
application and loop. See Sections 7.3, 7.4, and 7.5.
b) Calibrate the system, as described in Section 5.3.
c) Set up the user values for:
• Output High and Low - See Section 5.4.
• Control Relay - See Sections 5.8 and 5.9.
• Alarm Relay - See Sections 5.12 and 5.13.