5. TROUBLESHOOTING
Page 27
© 2007 DH Instruments, a Fluke Company
5
5
.
.
T
T
R
R
O
O
U
U
B
B
L
L
E
E
S
S
H
H
O
O
O
O
T
T
I
I
N
N
G
G
GPC1 is a sophisticated pressuring generating and adjusting instrument with advanced features and
functions. Before assuming that unexpected behavior is caused by a system defect or breakdown, the
operator should use this manual and other training facilities to become thoroughly familiar with GPC1
operation. This troubleshooting guide is intended as an aid in identifying the cause of unexpected GPC1
behavior and determining whether the behavior is due to normal operation or an internal or external
problem.
Identify the symptom or unexpected behavior you are observing from the
SYMPTOMS
listed in Table 3.
A
PROBABLE
CAUSE
is provided and a
SOLUTION
is proposed including references to manual
sections that provide information that may be of assistance.
Table 3.
GPC1 Troubleshooting Checklist
SYMPTOM
PROBABLE CAUSE
SOLUTION
Test pressure continuously increases
even with all valves closed.
Leak in
INLET valve
or leak in
PDVV
(+) valve(s).
Isolate leak to
INLET valve
or
PDVV (+)
valve
(s) by checking whether pressure
continues to increase when PDVV is at end
of stoke. Replace or repair valve(s) if qualified
to do so. 3.1, 3.2.3.
Test pressure continuously decreases
even with all valves closed.
Leak in
OUTLET valve
, leak in
PDVV (-) valve(s
), leak in test
system connected to GPC1 or
internal leak in GPC1 high pressure
gas system.
Identify and correct leak in test system if
present. Disconnect from test system and
plug GPC1
TEST ports
to test GPC1 alone.
Isolate leak to
OUTLET valve
or
PDVV (-)
valve(s)
by checking if pressure continues to
decrease when PDVV is in minimum end of
stroke position. Replace or repair valve(s) if
qualified to do so. 3.1, 3.2.3.
Test pressure takes too long to
stabilize or will never stabilize.
You are observing normal evolution
of pressure in an uncontrolled static
volume.
Reduce resolution of pressure reading to
appropriate level. Reduce test volume.
Increase stability of test tubings and vessels.
Wait longer for stability. Overshoot test point
and return to reduce stabilization time.
Test pressure takes too long to
stabilize or will never stabilize.
Leak in GPC1 or test system
connected to GPC1.
See troubleshooting tips “Test pressure
continuously increases…” and “Test pressure
continuously decreases…” above.
Test pressure takes too long to
stabilize or will never stabilize.
GPC1 and/or test system tubing is
contaminated with liquids that are
“plugging” tubes.
Thoroughly purge complete system.
3.2.5 and 4.2
PDVV will not increase pressure.
PDVV is at maximum end of stroke
position, PDVV drive air supply
pressure is not high enough, or
PDVV drive air supply is plugged.
Verify PDVV piston position and readjust if
necessary. Use
INLET valve
to increase
pressure. Increase PDVV drive air supply
pressure. Clean filter. 2.3.2, 3.1, 3.2.3
PDVV will not decrease pressure.
PDVV is at minimum end of stroke
position.
Verify PDVV piston position and readjust if
necessary. Use
OUTLET valve
to decrease
pressure. 2.3.2, 3.1, 3.2.3
Opening
INLET valve
does not
increase pressure.
TEST INLET SET regulator
is set
too low and/or external pressure
supply to low.
Check value of supply pressure on
TEST
INLET gauge
. Adjust
INLET regulator
,
increase supply pressure if necessary. 2.3.2,
3.2.1, Table 2
