Azbil JTD910S - Page 171

A-19
Appendix A Maintenance and Troubleshooting of this Device
(B) Judging the possibility of one-side clogging diagnosis
Judgment criteria
• The maximum value in either the one-side clogging simulation state
on the high pressure or low pressure side is smaller than the minimum
value under normal operating conditions.
• The difference between the minimum under normal operating
conditions and the maximum with simulated clogging is equivalent
to or larger than the difference between the minimum and maximum
under normal operating conditions.
Index value
Maximum value
under normal
operating conditions
Minimum value
under normal
operating conditions
Maximum value
under simulated
clogging
Minimum value
under simulated
clogging
Normal condition Simulated clogging
condition
The larger the dierence
between the minimum
under normal operating
conditions and
the maximum with
simulated clogging
Diagnosis is possible
(Case A)
• With simulated one-side clogging, the minimum index value on
either the high or low pressure side, or on both sides, is larger than the
maximum value under normal operating conditions.
• The difference between the index value under normal operating
conditions and the index value with simulated clogging is equivalent
to or larger than the difference between the minimum and maximum
values under normal operating conditions.
The following diagram is an example of such case. There may be times
when the index value will increase no matter which one of them gets
clogged.
Maximum value with simulated
clogging(High-pressure side)
There may be times when
the index value will increase
It is acceptable for the index
value to decrease sometimes
Minimum value with simulated
clogging(High-pressure side)
Maximum value with simulated
clogging(Low-pressure side)
Minimum value with simulated
clogging(Low-pressure side)
Maximum value under
normal operating conditions
Minimum value under
normal operating conditions
Index value
Normal condition Simulated clogging
condition
(High pressure side)
Simulated clogging
condition
(Low pressure side)
Diagnosis is possible
(Case B)
• The above conditions are not satisfied.
Diagnosis is not
possible or difficult.
If the diagnosis is judged to be possible, go to section A3-4-5 and set the diagnostic alarm.
If only the one-side diagnosis is judged to be not possible, go to section A3-4-7 and change the
settings to enable easier detection of one-side clogging, or set only both-side clogging for the
diagnosis target, and then set the diagnosis alarm as described in section A3-4-5.