129
2600T SERIES |  PRESSURE TRANSMITTERS |  OI/266/FF-EN REV. E
12  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. 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.
 CAUTION 
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 section).
 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.
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.
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 266DS/MS/PS/VS/RS 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.
Please contact your local ABB office for spare parts support
information or refer to the spare part list.
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 at the end of this manual and include
it with the device.
Removing/Installing the process flanges
•  Slacken the process flange screws by working on each in a 
crosswise manner (hexagon head, SW 17 mm (0.67 inch) for 
266DS/266PS/266VS or SW 13 mm (0.51 inch) for 
266MS/266RS).
•  Carefully remove the process flange, making sure that the 
isolating diaphragms are not damaged in the process.
•  Use a soft brush and a suitable solvent to clean the isolating 
diaphragms and - if necessary - the process flange.
•  Insert the new process flange O-rings in the process flange.
•  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).
•  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.
•  Lubricate the screw thread and seats of the screw 
connection.
•  While performing the preliminary and final tightening of the 
bolts, please act in a crosswise manner.