Emerson Bristol 2808 Series, Instruction Manual

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Appendix C Surge Protector / C-1
Appendix C
SURGE PROTECTOR
Pt. No. 388630-01-9
Transients caused by power and lightning surges can cause damage to field-mounted units.
Transmitter models without meters have bipolar, differential surge protection rated at 1000
watts for 1 millisecond. Consistent surges that exceed these levels could cause a failure of
the Transmitter's surge protection diode.
Additional protection can be achieved through the use of external devices. The optional
Joslyn 1669-02 Transient Surge Protector (Bristol Babcock Pt. No. 388630-01-9) provides
protection for surges up to 10000 amperes. The protector diverts excess surge currents
around the Transmitter and maintains the internal current at a low level.
The Transient Surge Protector is wired as shown in the illustration. The end having the
three wire leads (red, black and green) will screw into one of the 1/2 inch NPT conduit
openings of the Ttransmitter. The red lead connects to , black to SIGNAL-, and
green to the green grounding screw. The earth ground lead should also be connected to the
grounding screw. The red and black leads at the other end of the surge protector connect to
the + and
− side of the loop as shown.
The internal 44 ohms resistance of the Surge Protector must also be added to the loop
resistance when calculating the Transmitter's supply voltage.
Warning
The Surge Protector is not approved for operation in hazardous areas. Its use
is strictly limited to Transmitters that operate in non-hazardous installations.
Wiring Surge Protector Wiring Connections to 2808 Transmitter