Endress+Hauser Deltatop DP71B, Руководство по эксплуатации

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Operation and commissioning Deltatop DP71B, DP72B, DP73B
40 Hauser
Usage
The manifold is used to separate the Deltabar differential pressure transmitter from the process and
to perform zero point adjustment.
Operating principle
If the Deltabar differential pressure transmitter has to be removed from the measuring point (e.g. for
exchange or repair), it is possible to completely separate the transmitter from the process by closing
all the valves.
Commissioning
During commissioning, zero point adjustment should be performed on the Deltabar differential
pressure transmitter in any case. During initial commissioning, all the valves should be closed when
starting the process. Then the valves of the "-" and "+" side should be opened cautiously. The
equalization valve remains closed.
After this, make sure that the impulse pipes, the manifold and the transmitter are completely vented
(for liquids and steam) or drained (for gases).
Zero point adjustment
To perform zero point adjustment, first close the valve at the "-" side and then open the equalization
valves (3, 4), such that the "+" and the "-" side of the transmitter are exposed to the same static
process pressure (+). In this state, zero point adjustment of the Deltabar differential pressure can be
performed (refer to the Operating Instructions of the Deltabar). On completion of zero point
adjustment, the measuring system is put back into operation by performing the same steps in reverse
order.
Zero point adjustment should be checked and - if necessary - adjusted regularly. The measuring
system should also be checked regularly for complete venting or draining.
Venting/draining
The additional valves of 5-valve manifolds are used for venting or draining or to empty the impulse
pipes completely (e.g. for maintenance purposes). In steam applications these valves are used to
blow out the impulse pipes.
!
Note!
The complete venting or draining of the Deltabar differential pressure transmitter is always
performed by appropriate devices at the side opposite the transmitter flanges.
"
Caution!
If all three or four valves at the manifold are opened at the same time, the pressure difference may
cause the medium to flow through the manifold. With hot media, this may result in the manifold
and the Deltabar differential pressure transmitter overheating. Therefore, it is essential to avoid
opening all three valves simultaneously under operating conditions.