Tecsis P2590, Руководство по эксплуатации

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Differential pressure
is zero
Differential pressure
is measured again
Released
Valve butt
on
pushed
Operating instructions 17
BD_BE_460 d 06/2011
GB
6.3 Setting the switch point / checking the zero point
The switch points are set at the factory when the desired values are given. The
adjustment of the switch point is made by setpoint screws accessible from the
front. The assistant scales enable a relatively accurate adjustment of the switch
points over 270
p
° and indicate the setpoint that is momentarily adjusted.
For contact re-adjustment the snap-fit window is to be lifted off using a screw
driver at the recess in the circumference. The desired switch point can be set by
turning the contact adjustment screws with a screw driver.
If a more accurate switch point adjustment is desired, a test variable should be
used.
Afterwards press the window back into the case.
To check zero point see below
7. Options and accessories
7.1 Integrated pressure equalising valve
The zero point check during the working
process is enabled by pushing the valve
button. The measuring medium flows from
the higher pressure side to the opposite
side and the differential pressure drops to
zero.
When the valve button is pushed, the differential pressure pointer must move
into the range of the zero point tolerance bar. As a consequence the function of
the instrument is in order. In the case of possible deviations beyond the tolerance
bar a zero point correction can be made via a standard integrated adjustment
pointer. For that purpose the snap-fit window is to be lifted
off using a screw driver at the impression/recess in the
circumference. The zero point is corrected by turning the
slotted screw at the adjustment pointer. Afterwards the
window is to be snap-fitted to the case again. The differen-
tial pressure is indicated again, as soon as the valve button
is released.
6. Commissioning / 7. Options and accessories
Slotted
screw