General; Fitting In Position; Operating Conditions - JUMO 4AP-30 Notice De Mise En Service

3.2 General

The operating position of the pressure transmitter is generally unrestricted. However, in
unfavourable circumstances it may falsify the measured value.
Where there are unusual measurement conditions or media (e.g. high medium temperatures or
especially corrosive media), suitable pressure separators from our product range can be used.
Our staff will be pleased to give professional advice.
Unless otherwise specified, JUMO pressure transmitters have been calibrated vertically with the
pressure connection below, at an ambient temperature of 20×C.
For installation in hydraulic plant it is appropriate to mount the pressure transmitter with the
pressure connection above, to avoid air pockets.
When using a shut-off device, it should have a progressive opening to ensure a slow increase in
pressure. Shut-off devices should be opened slowly to avoid pressure surges.

3.3 Fitting in position

The sealing faces of the pressure transmitter and the measurement point must be protected against dirt and
damage. The type and form of the thread which is used at the measurement point is described on the back
of the instructions. In case of doubt, please contact the main factory.
The tightening torque depends on the form and material of the seal which is used, and on the pressure con-
nection. The tightening torque should be at least 15 Nm but not more than 200 Nm.
For pressure connections to EN 837 Form B, suitable seals are JUMO hydraulic seals to DIN 16 258 (flat), as
in Data Sheet 40.9700.
For pressure connections to DIN 3852 Form E, JUMO provides the appropriate elastomer seals ex-works,
ready-mounted in the pressure connection.
Pipe connections to DIN 11 851, DIN 28 403 (KF) and DIN 32 676 (clamp) include special sealing systems,
which can be provided as accessories on request.
For the special pressure connections to the pressure transmitter, with the Extra Codes /117, /131 and /141,
mating connections for welding are available as accessories in our product range.
The weld-in mating connection for Extra Code /44 is supplied with the package.
Taper pressure connections to American standards, such as NPT threads, are made hand-tight with a span-
ner. A sealing compound is used to prevent the material seizing up.

3.4 Operating conditions

The pressure transmitter must be earthed, and protected against electrostatic discharges!
The ambient and pressure-medium temperatures must not go beyond the limits that are given in
the corresponding Data Sheet.
As for any other sensitive measuring instrument,
the pressure transmitter must not be exposed to
excessively large variations in temperature.
These will eventually cause changes of the zero point and the measurement span.
Do not exceed the measurement range or the permitted overpressure.
For highly viscous or crystallizing media which could block the pressure connection, the most suitable
versions are those with a frontal diaphragm.
The frontal diaphragm must not be deformed under any circumstances – even finger pressure can be
enough to cause unacceptable deformation of
the diaphragm.
Do not insert any objects into the bore of the pressure connection.
Do not direct a pressure jet onto the diaphragm.
Under extreme conditions, with rapid changes of pressure and high pressure peaks, snubbers and pres-
sure decoupling elements must be applied, to avoid pressure spikes (water hammer) which would lead
to failure of the pressure transmitter.
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