39
O&M Manual
Rev-H (6/19)
Part - 7 Diagnostics Menu [DIAG]
The diagnostics menu contains all of the user settings that are specific to the system diagnostic
functions, as well as functions that aid in troubleshooting application problems.
Set Hold
The Set Hold function locks the current loop output values on the present
process value, and halts operation of the PID controller. This function can
be used prior to calibration, or when removing the sensor from the
process, to hold the output in a known state. Once HOLD is released, the
outputs return to their normal state of following the process input. The
transfer out of HOLD is bumpless on the both analog outputs - that is, the
transfer occurs in a smooth manner rather than as an abrupt change. An
icon on the display indicates the HOLD state, and the HOLD state is
retained even if power is cycled. Press ENTER to initiate user entry mode,
and entire value will flash. Use the UP arrow key to modify the desired
value, selections are
ON
for engaging the HOLD function, and
OFF
to
disengage the function. Press ENTER to store the new value. Note - the
Set Hold function holds BOTH current levels, as well as ALL relay settings.
The Set Hold function can also hold at an output value specified by the
user. To customize the hold value, first turn the HOLD function on. Press
the ESC key to go to the DIAG Menu and scroll to Sim Output using the
UP arrow key. Press ENTER. Follow the instructions under Sim Output
(see following page).
CAUTION: There is no time-out on the hold feature. Once placed
into hold mode, return to normal operation must be done manually.
Fault List
The Fault List screen is a read-only screen that allows the user to display
the cause of the highest priority failure. The screen indicates the number
of faults present in the system and a message detailing the highest priority
fault present. Note that some faults can result in multiple displayed failures
due to the high number of internal tests occurring. As faults are corrected,
they are immediately cleared.
Faults are not stored; therefore, they are immediately removed if power is
cycled. If the problem causing the faults still exists, however, faults will be
displayed again after
power is re-applied and a period of time elapses
during which the diagnostic system re-detects them.
The exception
to this rule is the calibration failure. When a calibration fails, no corrupt
data is stored. Therefore, the system continues to function normally on
the data that was present before the calibration was attempted.
After 30 minutes or if power to the analyzer is cycled, the failure for
calibration will be cleared until calibration is attempted again. If the
problem still exists, the calibration failure will re-occur. Press ENTER to
initiate view of the highest priority failure. The display will automatically
return to normal after a few seconds.
Sim Out
The Sim Out function allows the user to simulate the chlorine level of the
instrument in the user selected display range. The user enters a ppm
value directly onto the screen, and the output responds as if it were
