Emerson Bristol 2808 Series, Instruction Manual

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2808B Service / 4-1
Section 4
SERVICE
4.1 GENERAL
Servicing should only be performed by technically competent persons skilled in the use of
pneumatic and electronic test equipment and having knowledge of troubleshooting
procedures.
After any service procedures are completed, the Transmitter cover must be installed and
properly tightened. A failure to secure the cover will result in a loss of the enclosure's dust-
tight, water-tight seal and explosion-proof rating.
Warning
No attempt should be made to service a Transmitter while it is powered and
operating in a flammable or explosive environment. Either the area must be
made safe or the Transmitter must be powered down, disconnected, and taken
to a safe, non-hazardous area.
4.2 TROUBLESHOOTING
Some troubleshooting procedures will require that you use a digital multimeter (DMM) to
measure the loop current. Connect the DMM across the V and (+) terminals of the
Transmitter as shown in Figure 4-1 and set it to its "milliampere" function. This method of
connection will not disturb the signal/power loop. The DMM reading will be proportional to
the input pressure and cover a range of 4-20 mA.
4.3 FACTORY REPAIRS
If you determine that a fault is present in the Transmitter's PC board or pressure sensor,
do not attempt any service as specialized factory equipment and test procedures will be
required. Defective Transmitters may be returned to
Bristol Babcock for evaluation or
repairs. Transmitters in warranty will be repaired or replaced per the warranty agreement
contained at the end of this manual. A “Repair Authorization Form” (6th page of this
manual), must be filled out and included with returned instruments.