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7.4.1 Zero point adjustment
The devices are supplied calibrated ex works, so that as a rule there is no
need for calibration operations at the installation point. However, it is
possible to adjust the zero point on site, and this is performed as follows:
Switch the pressure metering pipe so that it is depressurized, or
charge it with the existing static pressure.
Open the front face of the device, by loosening the bayonet ring. This
may require a belt wrench.
Hold the pointer in place and adjust the pointer bushing using a
screwdriver, until the pointer (when released) is pointing correctly to
zero.
Close the case again and ensure that the seal, glass plate and locking ring are seated correctly.
Liquid-filled devices must be dismantled for the zero point adjustment, and placed on a horizontal surface
for adjustment, since otherwise the liquid would run out.
7.5 Subsequent
relocation
of
the gauge (by the customer)
Recommendation:
Do not remove the pressure gauge from one metering point and fit it in a different
place, as there is a risk of the measuring media being mixed, with unforeseeable chemical reactions.
8 Servicing
The device is maintenance-free. However, to ensure reliable operation and a long lifetime for the device, we
recommend that it is checked regularly.
8.1 Safety
When undertaking servicing work on the device, the pressure lines must be depressurized and the plant secured
against being switched on again.
8.2 Check on function, and recalibration
The check on function and recalibration is carried out at regular intervals, depending on the application. The precise
testing cycles should be adjusted in line with the operating conditions and ambient conditions. In the event of various
device components interacting, the operating instructions for all other devices should also be taken into account.
Check on display.
Check on function, in conjunction with downstream components.
Check of pressurized connection pipes for seal condition.
Check of electrical connections.
8.3 Cleaning
and
maintenance
Cleaning is carried out using a non-aggressive cleaning agent, respecting the protection category of the device.
9 Faults
9.1 Safety
Defective or faulty pressure gauges put the operational safety and process safety of the plant at risk, and can lead to a
risk of injury to persons, the environment or the plant.
9.2 Conduct in the event of faults
All defective or faulty devices must be taken out of service. If a repair is required, the device must be sent directly to
our Repairs Department. We request that all returns of devices are agreed with our Service Department.
