Process Connections; Temperature Measurement; Mounting Recommendations - ABB 2600T Series Operating Instruction

8.10 Process connections

Fig. 18
On the flange of the 266 multivariable transmitter there are
1/4 – 18 NPT process connections with middle point spacings
of 54 mm (2.13 in.). The process connections on the flange
enable direct attachment of 3 element or 5 element valve
manifolds.
Optionally flange adapters with 1/2 – 14 NPT connections are
available. By turning one or both adapters, middle point
spacing of 51 mm (2.01 in.), 54 mm (2.13 in.) or 57 mm
(2.24 in.) is possible.
Mount the adapters as follows:
1. Correctly position the adapters with inserted O-ring.
2. Screw the adapters on the transmitter connection flange
with the provided screws.
Tighten the screws as follows: Preliminary tightening hand
tight, preliminary tightening with 10 Nm, final tightening
with 50 Nm.
26 OI/266CXX/266JXX/HART-EN Rev. B | 266CRx, 266JRx, 266CSx, 266JSx

8.11 Temperature measurement

— Mount the temperature sensor in the downstream pipe of
the primary element.
— Consider the downstream straight pipe requirements .
— If there is a significant difference between the temperature
of the measuring medium and the ambient temperature,
the measuring error caused by heat conduction must be
minimized by insulating the installation location
accordingly.
— Use class "A" sensors to maximize accuracy.
— The lengths of the protective tubes should be
15 ... 20 times the diameter of the protective tube for gas
measurements and 3 ... 5 times the diameter of the
protective tube for liquid measurements.

8.12 Mounting recommendations

The arrangement of the impulse lines depends on the
respective measurement application.