Calibration Of The 4700 E/4800 E Positioner; Maintenance Service; General Rules; Before Maintenance Activity - GE 4700E Instruction Manual

9. CALIBRATION OF THE 4700 E/4800 E POSITIONER

Comply with current national and local regulations for electrical installation work.

Comply with national and local explosive atmosphere regulations.

 Before carrying out any work on the device, power off the instrument or make sure that the local
conditions in the potentially explosive atmosphere permit the safe opening of the cover.
Before switching on or after doing any work on the device, always tighten the cover (C) with a seal (J)

in good condition and put back the safety screw (V).
The positioner mounted on the valve is factory calibrated. If it is supplied alone, calibration will be carried out by
the customer, as follows:
 Make the electrical and pneumatic connections, see § 5 and § 7.
 The zero is set using the nut (4b). Adjust the nut (4b) so that the valve is close for the signal value that
corresponds to the closure of the valve.
 The span is adjusted using the spring (5). Turn the spring (5) on the spring end (4), to increase or reduce the
number of active coils, thus reducing or increasing the stiffness of the spring. These operations are carried out to
adjust the span so as that the valve describes its entire stroke for the full range of the control signal.
 These two operations are repeated until the correct settings are obtained.
 Lock the zero lock nut (4c) and the socket head screw (8)
Note: the Model 4000 I/P Converter does not require any adjustment.

10. MAINTENANCE SERVICE

 Comply with current national and local regulations for electrical installation work.
 Comply with national and local explosive atmosphere regulations.
Before carrying out any work on the device, power off the instrument or make sure that the local

conditions in the potentially explosive atmosphere permit the safe opening of the cover.
Before switching on or after doing any work on the device, always tighten the cover (C) with a seal (J)

in good condition and put back the safety screw (V).

10.1. General rules

These operations must be put into service in conformance with EN/IEC 60079-17 and / or national and local
regulations applicable for explosive atmospheres.

10.2. Before maintenance activity

Before carrying out any work on the device, check that the local conditions in the potentially explosive atmosphere
zone permit the safe opening of the cover (C).

10.3. During maintenance activity

Take into account all special conditions of use points listed § 11.
Pay particular attention to the following points:

Check that no part is damaged. In the event of damage, replace the defective parts with genuine
manufacturer's replacement parts only.
 Check the general condition of the main cover seal (C) and the housing.
 Check the gland and the electrical connections.
 Check the pilot:
Disconnect the air supply and remove the pilot from the pneumatic block
After disassembly of the pilot (see picture below) clean parts and blow air through the ports and tubing.
The reassembly of the pilot is done in accordance with the figure below by using three new O rings.
Screw the assembly in the pneumatic block.
ATEX Instruction Manual GEA19513 – 03/2012
4700E and 4800E Series Electropneumatic Positioners
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