Metex 2200R ORP Analyzer/Controller - Manual (Page 26)

Model 2200R Page 24
9.0 TROUBLESHOOTING AND SERVICE
9.1 Calibration / Display Problem
3.5.1 If the problem is one of inability to calibrate or the display does not appear to match
the input, try the RESET feature. See Section 6.4. In rare cases, the ESCAPE
feature might be used. Refer to Section 9.3.
9.2 Isolate the cause
9.2.1 When a measurement problem occurs, the first step is to try to isolate the cause. If
the 2200R is powered, go through the menu and check your settings. A convenient
way to do this is to call TEST. Refer to Section 5.12
3.5.1 If your 2200R appears dead or intermittent, check the breaker, make sure that the
instrument is set up for the available line voltage and make sure the line voltage is
actually available at the terminals. Now measure that sufficient voltage is available
at all times; it should be 98 Vac to 132 Vac or 187 Vac to 243 Vac respectively.
Shut line power off, making sure it is off. CAUTION: Power to the relays may be
supplied from a separate source, shut it off too. Check and if necessary replace the
internal 0.25A fuse. Push the connector of the ribbon cable firmly into its socket. If
these steps do not solve the problem it may be necessary to replace the power
supply board. Refer to Section 9.4 below.
9.2.3 Should your process control element e.g. pump, valve or alarm not be activating,
check that the correct power is supplied to the "floating” relay contacts, jumped over
from the line voltage terminals or perhaps from a separate breaker or DC supply.
Use the TEST menu feature to simulate the input values to observe the switching
points.
Check that your process control elements can function independently of the 2200R.
Next check with a test light or an Ohmmeter (power off to the relay contacts, wires
to the control elements disconnected) that the contacts of the respective relay are
making contact when actuated. If a relay is malfunctioning, it may be necessary to
change it. Refer to Section 9.5.
3.5.1 If the process value seems wrong, clean the probe as described in the probe
manual. Inspect the probe, wire and interconnections. Open the inner door and
ensure that the two jumpers J42 are in the correct position for the probe used and
the probe wires are correctly and firmly connected. See Sections 3.5 and 3.6. Now
place the probe into a 7 ORP buffer. Rinse, and place it into a 10 ORP or 4 ORP
buffer while observing the panel meter. If the values are close, re-calibrate and
resume operation. Should there be a major discrepancy, bring the probe and
buffers to the 2200R, connect directly to the 2200R and repeat the procedure. If
that does not solve the problem, replace the probe.
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
(R60 series), or S41 if you are using a conventional probe (P500 series), from
position “ON LINE” to position “TEST”. Turn the ORP simulation potentiometer
R65 from end to end. The display should change between 0 and 1000mV. If
this is the case, the analyzer is in order, and the problem is in the sensor.
Otherwise the problem is in the analyzer.