Endress+Hauser NRF590 Kurzanleitung Seite 3

Exchange / assembly of I/O-module on the power supply on the Tank Side Monitor NRF590
Only identical, original E+H spare parts may be used.
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The instrument may only be maintained and repaired by qualified personnel. The device documentation, applicable standards and legal
requirements as well as any certificates have to be observed!
Ex i-devices:
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Ex d-devices:
Before disassembly ensure that the supply voltage for the instrument has been switched off.
The exchange requires the following tools:
• Philips screw driver size 1 and 2
• Hexagonal key AF 3 mm
• Flat pliers
• Eventually a pair of tweezers
New design of
display holder
Disassembly the power supply / assembly the I/O-module
1. Loosen the safety pin for the lid (AF 3 mm) approx. 4 turns.
2. Unscrew the lid (7 turns). Note:
attempt once again to unscrew lid.
3a. Grip the sides of the display and push in on each side to snap the display out.
3b. Open the cover of the display holder.
4. Push on the cable´s retainer clips and unplug the cable.
5. Unscrew the 2 screws of the display holder to the electronics compartment and remove holder.
6. Remove power supply carefully (if need be use a flat pliers).
KA591F/00/a2/09.07
52016534
Ausgabe/revision: 3
The repair has to be performed such, that the voltage isolation of the Ex ia circuits against ground is maintained.
If required, a test can be performed with 500 Veff over a time period of 60 s.
Attention has to be paid not to damage the threads.
Before assembly, the threads of the lids and the sensor module must be lubricated with acid-free grease. It is not
necessary if the threads are coated with a non-greasy dry-lubricating material.
Power supply
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Old design of
display holder
3b
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If the lid is difficult to unscrew, unplug one of the cables from the cable gland to allow air to enter the housing. Then,
Note:
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4
Safety pin
hexagonal key
AF 3 mm
Don´t pull on the flat cable!
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