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2 6 6 H S H MODBUS TR A N S M IT TE R |
P R E SSU R E/ T EM P ER AT U R E M U LT I VA R I A B L E | O I/ 2 6 6 H SH M T- EN R E V. A
9 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.
9.1 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.
9.2 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.
9.3 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.
