Current Output; Service And Maintenance - juenemann-instruments MANFRED JÜNEMANN DE20 Instructions D'utilisation

1.0 Service intended
For gaseous and liquid media that will not obstruct the pressure system.
2.0 Installation and Commissioning
The pressure tapping points should be prepared in accordance with the indications given for the sockets. For
more details, see e.g. regulation VDE/VDI 3511 and 3512, sheet 3.
Suitable for sealing are sealing washers to DIN 16258. The correct tightening torque is depending on material
and shape of the used seal. It shold not exceed 80 Nm. The mounting position should not be subject to strong
vibration and radiation heat. The differential pressure transmitters with digital display are immediately ready for
service after the pressure and electrical connections have been made.
3.0 Wiring
Electrical connection is made by shielded cable and means of the cable box. Precise wiring schemes can be
seen in the drawings. For the electrical connection a shielded cable with conductor cross section upto max.
1,5 mm must be used.
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Significance of applied terminal designations:
Ub+ / OV = supply voltage

3.1 Current output

Output signal: 0 ... 20 mA / 3 wire-system (LED/LCD)
4 ... 20 mA / 3 wire-system (LED/LCD) / 2 wire-system (LCD)
Power supply: Ub = 17 ... 30 V DC
max. load: Ra = (Ub - 17 V) / 20 mA
If current output not used, please connect terminal 2 and 3.
3.2 V Signal
Output signal: 0 ... 10 V / 3 wire-system (LED/LCD)
Power supply: Ub = 17 ... 30 V DC
max. load: Ra ≥ 10 kΩ

4.0 Service and Maintenance

The differential pressure transmitter with digital display described hereunder is maintenance free. It incorpo-
rates no components which have to be repaired or replaced on the site. Repairs will exclusively be carried out
at the factory.
Depending on working conditions, the differential pressure transmitter should be checked about once a year
to ensure that they are within their specifications and be adjusted if necessary. The calibration procedure is
as follows:
- As reference for checking and adjusting the measuring span, an adequately accurate pressure standard is required.
- For readjustment, loosen, with a left-hand rotation, the cam ring (bayonet type), and remove from casing with the window.
- Set zero point via potentiometer „ZERO".
- Set span via potentiometer „SPAN".
- After having carried out service and maintenance work, lock tightly the instrument with the cam ring (bayonet
type), the window and the sealing.
S+ / S- = output signal protection / PE = cable shield
Quality for the
future
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