OEM OPM223, Operating Instructions Manual

Page: 69 / 104

OPM223/253 Maintenance
69
7 Maintenance
Take all the necessary measures in time to guarantee the operational safety and reliability of
the entire measuring system.
Maintenance work at the transmitter comprises:
• Calibration (see "Calibration" section)
• Cleaning of assembly and sensor
• Cable and connection check
#
Warning!
• When carrying out all work on the device, please observe any possible effects on the process
control or the process itself.
• When removing the sensor during maintenance or calibration, please consider potential
hazards due to pressure, high temperatures and contamination.
• Make sure the device is de-energised before you open it.
If work must be carried out when the device is live, this may only be performed by an
electrical technician!
• Switching contacts can be fed by separate circuits. These circuits must also be de-energised
before work on the terminals is performed.
Caution ESD!
• Electronic components are sensitive to electrostatic discharge. Personal protective
measures such as discharging at the PE beforehand or permanent grounding with a wrist
strap are required.
• For your own safety, use only genuine spare parts. With genuine spare parts, the function,
accuracy and reliability are also guaranteed after repair.
!
Note!
If you have any queries, please contact your local Sales Office.
7.1 Maintenance transmitter
7.1.1 Dismantling of panel mounted instrument
"
Caution!
Please note the effects on the process if the device is taken out of service!
!
Note!
Please refer to the diagram in Section "Spare parts" for the item numbers.
1. Disconnect the terminal block (item 422 b) from the rear of the device to de-energise the
device.
2. Then remove the terminal blocks (item 422 a and poss. 430) from the rear of the device.
Now you can disassemble the device.
3. Press in the latches of the end frame (item 340) and remove the frame from the rear.
4. Release the special screw (item 400) by turning it counter-clockwise.
5. Remove the entire electronics block from the housing. The modules are only mechanically
connected and can be easily separated:
– Simply remove the processor/display module from the front.
– Pull out the brackets of the rear plate (item 320) slightly.
– Now you can remove the side modules.
6. Remove the pH/mV transmitter (item 230) as follows:
– Bend the screening plate up.
– Disconnect the connected strand (pH input, strand comes from the BNC connection
jack).
– Using a fine side-cutting pliers, nip off the heads of the synthetic distance holders.
– Then remove the module from above.
Assembly is the reverse of the disassembly sequence. Tighten the special screw hand-tight
without a tool.