Maintenance; Returns And Removal; Pressure Transmitter Sensor; Removing/Installing The Process Flanges - ABB 266 HART Series Operating Instruction

10 Maintenance

If transmitters are used as intended under normal operating
conditions, no maintenance is required. It is sufficient to check
the output signal at regular intervals (in accordance with the
operating conditions), as described in the instructions in the
section "Operation resp. Configuration of the transmitter". If
deposits are expected to accumulate, the measuring
equipment should be cleaned on a regular basis, in accordance
with the operating conditions. Cleaning should ideally be
carried out in a workshop.
Important. In case of aggressive environment and any critical
condition, ABB recommends to check O-rings periodically. In case
of damage, user shall replace them with original spare parts.
Repair and maintenance activities may only be performed by
authorized customer service personnel.
When replacing or repairing individual components, original
spare parts must be used.
Attention – Potential damage to parts. The electronic
components of the printed circuit board can be damaged by static
electricity (observe ESD guidelines). Make sure that the static
electricity in your body is discharged when touching electronic
components. If a remote seal is mounted on the measuring
equipment, it must not be removed (please refer to the dedicated
document).
Warning – <Bodily injury>. Explosion-proof transmitters must be
either repaired by the manufacturer or approved by a certified
expert following repair work Observe the relevant safety precautions
before, during and after repair work. Only disassemble the
transmitter to the extent necessary for cleaning, inspection, repairs,
and replacement of damaged components.

10.1 Returns and removal

Defective transmitters sent to the repairs department must,
wherever possible, be accompanied by your own description of
the fault and its underlying cause.
Warning – General risks. Before removing or disassembling the
device, check for hazardous process conditions such as pressure
on the device, high temperatures, aggressive or toxic media, and
so on. Read the instructions in the sections "Safety" and "Electrical
connection", and perform the steps outlined there in reverse order.
64 OI/266/HART-EN Rev. M | 2600T Series Pressure transmitters

10.2 Pressure transmitter sensor

Essentially maintenance is not required for the transmitter
sensor. Anyway the following items should be checked
periodically:
— Check the integrity of the pressure boundary (no cracks
should be visible on the process connection or on the
process flanges.
— Check that there is no leakage from the sensor/flange
interface or from the vent/drain valves.
— The process flanges bolts (for 266DSx/MSx/PSx/VSx/RSx
models) should not show excessive rust.
In case one of the check points above fails, please replace the
damaged part with an original spare part.
The use of non original spare parts makes the warranty void. In
case you want ABB to perform the repair, please send back the
transmitter to your local ABB office complete with the return
form that you find in this manual appendix and include it with
the device.

10.3 Removing/Installing the process flanges

1. Slacken the process flange screws by working on each in
a crosswise manner (hexagon head, SW 17 mm
(0.67inch) for 266DS/266PS/266VS or SW 13 mm (0.51
inch) / SW 17 mm (0.67 inch) for 266MS/266RS).
2. Carefully remove the process flange, making sure that the
isolating diaphragms are not damaged in the process.
3. Use a soft brush and a suitable solvent to clean the
isolating diaphragms and - if necessary - the process
flange.
4. Insert the new process flange O-rings in the process
flange.
5. Attach the process flange to the measuring cell.
The surfaces of both process flanges must be at the same level
and at a right angle to the electronics housing (with the
exception of vertical process flanges).
6. Check that the process flange screw thread can move
freely: Manually turn the nut until it reaches the screw
head. If this is not possible, use new screws and nuts.
7. Lubricate the screw thread and seats of the screw
connection.
8. While performing the preliminary and final tightening of the
bolts, please act in a crosswise manner.
Attention – Potential damage to parts. Do not use sharp or
pointed tools.
Do not damage the insolating diaphragms.
Important. In the case of oil and grease-free designs, clean the
measuring chambers again if necessary once the process flange
has been installed.
10 Maintenance