Emerson Bristol 2808 Series, Инструкция по эксплуатации

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1A-12 / GP Transmitters 2808B
1A.6 SERVICE CHECKS
General troubleshooting hints are listed in Table 1A-C. Some of these checks will require a
digital multimeter (DMM). The DMM may be connected across the (+) and (V) terminals to
measure current directly without opening the current loop. See Section 4 Service for details.
TABLE 1A-C - TROUBLESHOOTING CHECKS
SYMPTOM RECOMMENDED CHECK
Low or no output:
Consistent Output Errors:
Fixed Output:
Erratic Output: Check power supply for low dc output.
Check field wiring for shorts, opens, grounds or
excessive resistance.
Check that shutoff valves are fully open.
Check for leaks in the connecting line or at
the transmitter connection.
Check for sediment or clogging in the connecting
line or at the transmitter connection.
Check for gas in liquid lines, or liquid in gas
lines.
Check zero and span adjustments using calibration
test setup.
Check that shutoff valves are fully open. Pressure
may be trapped in the connecting line.
Amplifier board may be defective.
Check loop wiring for shorts, opens, grounds or
intermittent connections.
Check piping for gas in liquid lines, or liquid in
gas lines.
Amplifier board may be defective.
1A.7 GP TRANSMITTER SPECIFICATIONS
Specifications that apply to the Model 2808-15B and 2808-16B Transmitters are listed
below. Those specifications that are common to all 2808 transmitters are contained in
Section 5 Specifications.
Maximum Input Ranges: 0-100 inH2O to 0-5000 psi (see Table AD for
details)
Overpressure Effect: +0.2% URL at maximum operating pressure