Instruction Manual
D200160X012
4195K Controllers
July 2018
52
Table 6‐1. Troubleshooting Chart
Fault
Possible Cause
Check
Correction
1. Process wanders or cycles about
set point
1.1 Proportional band and reset
settings
1.1 Refer to the startup procedures
for controller settings
1.1 If stable control cannot be
attained, and all other elements of
the loop are functionally correct,
examine other possible causes
related to the controller
1.2 Supply pressure varying
1.2 Monitor the supply pressure
with an external gauge. Ensure that
it is set correctly and does not
fluctuate. Note the number of
instruments being supplied by the
regulator
1.2 Correct as necessary. One
regulator per instrument is
recommended
1.3 Process pointer rubbing on
cover or scale
1.3 Note if the pointer is bent
1.3 Bend pointer to provide
clearance
1.4 Input element failure
1.4 Inspect the element for loose
screws and damaged flexures, links
or pivots. Using a soap solution,
check the sensing element for leaks
1.4 Repair or replace parts as
necessary
1.5 Linkage failure
1.5 Check for links that are bent or
not connected properly, flexures
bent or broken, pivots broken
1.5 Replace or repair as necessary
1.6 Relay malfunction
1.6 By changing the process set
point and observing the output
verify that the output will change at
about the same rate in both
directions.
1.6 If the output changes quickly in
one direction and sluggishly in the
other, replace the relay
1.7 Anti‐reset windup differential
relief valve set too low (suffix letter F
only)
1.7 The minimum relief valve
setting is dependent on the loop
dynamics and the controller
settings. If under normal load
changes, the relief valve opens,
instability can occur. Check by
observing the controller reaction to
a set point or load change under
closed loop conditions
1.7 If the differential relief valve
appears to be set too low, refer to
the section of this instruction
manual that covers the anti‐reset
windup option
2. Controlling off set point as
reflected by process and set point
indicators.
Note: Some offset is inherent with
proportional‐only controllers
(4195KA controllers). The amount of
offset is a function of the
proportional band setting
2.1 Supply pressure not set
correctly
2.1 Check with an external source
2.1 Reset the supply pressure if
necessary. If the condition occurs
again, the regulator should be
rebuilt or replaced
2.2 Flapper not aligned
2.2 Refer to the flapper alignment
procedure
2.2 Align the flapper as necessary
2.3 Leak in input element/tubing
assembly
2.3 Using soap solution, check the
input element and tubing for leaks
2.3 Repair or replace parts as
necessary
2.4 Indicators out of calibration
2.4 Refer to the process indicator
(and remote set if applicable) zero
and span calibration procedures in
this manual
2.4 Adjust as necessary
2.5 Linkage not connected correctly
2.5 Inspect for loose screws and
damaged flexures, links or pivots
2.5 Repair or replace parts as
necessary
2.6 Leak in feedback system
2.6 Open the reset valve to 0.1
minute/repeat. Adjust output
pressure to 1.4 bar (20 psig). Using
soap solution, check for leaks in the
proportional and reset bellows in the
tubing that connects these bellows
2.6 Repair as necessary
