Maintenance - Emerson Fisher 4200 Series Instruction Manual

4200 Series Transmitters
29A6206-C / DOC

Maintenance

WARNING
To avoid personal injury or property
damage from the sudden release of
pressure:
D Always wear protective clothing
and eyewear when performing any
maintenance operations.
D Disconnect any operating lines
providing air pressure, electric power,
or a control signal to the actuator. Be
sure the actuator cannot suddenly
open or close the valve.
D Use bypass valves or completely
shut off the process to isolate the
valve from process pressure. Relieve
process pressure on both sides of the
valve.
D Use lock-out procedures to be
sure that the above measures stay in
effect while you work on the
equipment.
D Check with your process or safety
engineer for any additional measures
that must be taken to protect against
process media.
22
Figure 10. Schematic Diagram for the Field Printed Wiring Board
NOTES:
1
RELAYS K1 AND K2 ARE SHOWN IN THE DE-ENERGIZED POSITION.
(TRIPPED POSITION)
On an explosion-proof instrument,
remove the electrical power before
removing the instrument covers in a
hazardous area. Personal injury or
property damage may result from fire
and explosion if power is applied to
the instrument with the covers
removed, in a hazardous area.
Test equipment for the following procedure is listed
in the Calibration section. Voltage references in this
procedure may vary depending on the temperature
of the instrument. The voltages below are taken at
approximately 22_C (72_F) ambient temperature.
Electrostatic voltages present in the
environment may be transferred to the
transmitter printed wiring board which
may cause failure or degraded
performance. Use appropriate
antistatic procedures when working
with the printed wiring board to protect
the electronic circuits.
The following procedures consider the instrument
assembled with all components installed according
to the type number description. The following
procedures can be used in the field or for a bench
check. Connect the instrument as shown in figure 8
for bench check.
Instruction Manual
Form 5596
July 2005
WARNING
CAUTION