ABB 266CSH User Manual

266CRH / 266CRT, 266CSH / 266CST MULTIVARIABLE PRESSURE TRANSMITTER | OI/266CXX/MODBUS-EN REV. A 17
Venting / draining transmitters without diaphragm
seals
WARNING
Damage to health / danger of death due to leaking
measuring medium!
Measuring medium can leak from the vent valve / drain valve
during venting or draining.
To avoid any danger due to leaking measuring medium,
please observe the following points:
• Wear protective clothing suited for the measuring medium
during venting or draining.
• Safely collect any leaking measuring medium and dispose
of it in an environmentally safe manner.
M10797-01
1 2 3
1 Valve on the process axis
2 Flange side valve on top
3 Flange side valve on the bottom
Figure 4: Possible positions of vent / drain valve
For transmitters without diaphragm sealers the following
instructions on venting and draining must be complied with.
It is important to attach the transmitter in such a manner and to
layout the process line in such a manner that gas bubbles in
liquid measurements can be routed back into the process and
not get in to the measuring chambers.
The optional vent / drain valves on the transmitter are attached
on the measuring cell flanges. Align the transmitter so that these
vent / drain valves are arranged above the tap points for liquid
measurement, so that gas can escape upward. For gas
measurements align the transmitter so that the vent / drain
valves are arranged below the tap points, so that air or
condensate can drain.
Mounting position
The pressure transmitter can be attached directly on a valve
manifold provided for flange installation.
Optionally a fastening bracket for wall or pipe installation
(2 in pipe) is available as an accessory.
For models 266CRx fastening brackets must always be used.
Ideally the pressure transmitter must be mounted in such a
manner that the separating diaphragms are standing vertical, to
avoid later zero point offsets.
Note
If the pressure transmitters are mounted with an inclination that
is not vertical, the filling fluid exerts hydrostatic pressure on the
measuring diaphragm, which causes a zero point offset.
In this case the zero point can be adjusted via the zero point
button or with the command ‘Set PV to Zero’. See Overview of
parameters on the configuration level on page 49.
Change from two to one column

ABB 266CSH Specifications

General

Brand	ABB
Model	266CSH
Category	Transmitter
Language	English