User Manual

Model 2200P Page 29
9.2.5 To find out whether the problem is in the sensor, or in the analyzer, use the self-
testing features. Do not disconnect the sensor. Proceed as follows:
a) Move the slide switch S40, if you are using an AquaMetrix differential probe
(P60 series), or S41 if you are using a conventional probe (P500 series), from
position “ON LINE” to position “TEST”. Turn the pH simulation potentiometer
R65 from end to end. The display should change between 0.00 and 14.00 pH.
If this is the case, the analyzer is in order, and the problem is in the sensor.
Otherwise the problem is in the analyzer.
b) To check the temperature channel move the slide switch S41 from position “ON
LINE” to position TEST. Go to the TEMPERATURE Menu item. The display
should be 25.0°C ± 0.1°C, in which case the analyzer is in order and the
problem is in the sensor. Otherwise the problem is in the analyzer.
For normal operation both slide switches S40 and S41 must be in
“ON LINE” position.
9.3 “Escape” Procedure
9.3.1 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 6.4.1.
9.3.2 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 AquaMetrix, or in case
of a memory loss problem, when so advised by AquaMetrix service support.
9.3.3 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 true for the control relay on and relay off
setpoints, the alarm settings and the analog outputs scaling. Also, the temperature
and the pH calibration points will be set to their initial values. This means, that the
temperature and the pH 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.
9.3.4 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 t he
power. The STATUS LED will turn red and status code 7 will be obtained to
show that the "ESCAPE" procedure was just performed.