Maintenance Instructions; Cause Of Fault - BD Sensors KHP 4002 User Manual

NOTE: After increasing the pressure, the reading may slightly drop again
for about 30 seconds, which is caused by thermodynamic effects, the tube
connection and the sealing gaskets. lf the pressure drop does not come to
a standstill, check the measuring circuit for tightness.
- A pressure reduction is achieved by turning the fine adjustment valve (4) anticlockwise
first and then by carefully opening the relief valve (2).
Remove the reference instrument or the test specimen only when the re-
lief valve is open and no pressure is in the test pump any more.
If the pressure test pump is used with water, the reservoir must be emptied after
each usage of the pump.

5. Maintenance Instructions

Prior to connecting the reference instrument and the test specimen, the sealing gaskets in
the two connectors should be checked for correct position and wear, and should be re-
placed, if and when necessary. A service kit, consisting of spare sealing gaskets and o-
rings, is available as an accessory.
The test pump KHP 4002 and KHP 6002 must not be soiled, and in particu-
lar it must not get into contact with fluid or aggressive media.
If the pressure test pump is used with water, the reservoir KHP 7003 / KHP
1004 must be emptied after each usage of the pump.
If any dirt or particles are visible inside the fluid reservoire, you must
change the fluid immediately.

6. Cause of fault

• If the pressure or vacuum cannot be generated correctly or if the set pressure or
vacuum does not stay stable, this is likely to be caused by the incorrectly positioned
or selected sealing gaskets. Please also check whether any adapters used on the
test specimen have been tightened sufficiently to eliminate leaks.
• Before assuming there is a leak in the calibration test pump: First of all, check if the
relief valve (3) is closed and if the pressure / vacuum change-over switch (4) is cor-
rectly positioned and has not come to rest in a "centre position".
• If the test pump has not been used for a longer period of time, the first lift may be
somewhat sluggish. This effect will disappear again during further operation.
• By no means apply any force to the operating elements of the calibration test pump.
• Never connect an external pressure supply system to the KHP 4002 / KHP 6002
pump.
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