Thermo Scientific Sarasota SG901, Руководство пользователя

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Troubleshooting & Service
Troubleshooting Sarasota SG901 / CM515 Density Systems
Thermo Fisher Scientific Sarasota SG901 User Guide
7-3
Table 7–2. Troubleshooting steps for Sarasota SG901 / CM515 density systems
Symptom Possible Fault Resolution / Further Investigation
Sarasota CM515
display is blank or
backlight is not on.
- No power to instrument.
- Display is configured to switch
off after a predetermined time.
- If there is no power to the instrument the RUN LED will not be
lit. In this case, check power at the terminal connections.
- If power is available at the terminals, check the DC voltage
available at the EXC V terminals (with respect to Ground). If
voltage is available here, the PSU is operational.
- If voltage is not available, the PSU is faulty and requires repair.
- If power is available and the RUN LED is lit, press the
DISPLAY key. If the display comes on, it is likely that it is
configured to go off after a set period of inactivity. Change the
configuration to disable display timeout.
System gives Zero
reading for SG.
- Density calculated value is
zero or negative.
- If the main density is zero, check the period input. If the period
input is close to the expected period (read from the calibration
sheet), check if pressure and temperature readings are within
the expected ranges. If the period, pressure, and temperature
readings are in the correct ranges, verify the entered constants
T0, D0, K, TC, and PC are correct as per the calibration sheet 1
(constants for 15°C).
- If the temperature is in gross error, check the thermometer
connections and configuration.
- If the connections are correct at the Sarasota CM515, check
the configuration. Also verify the thermometer values are
correct at the meter connections (WY and XZ).
System gives Zero
reading for SG.
- Temperature is in gross error.
- Pressure reading is –ve. - If the temperature is in gross error, check the thermometer
connections and configuration.
- If the connections are correct at the Sarasota CM515, check
the configuration. Also verify the thermometer values are
correct at the meter connections (WY and XZ). Check that any
fitted barriers are continuous (no blown barriers fuses).
System gives Zero
reading for SG.
- Pressure input is incorrect. Check the following:
- Input is connected correctly.
- Voltage available at the pressure transmitter terminals is
greater than 8 volts.
- Any fitted barriers are continuous (no blown barrier fuses).
- Configured Full Scale and Zero are correct and the input is
not set to default.
System gives Zero
reading for SG.
- Period reads Zero or grossly
outside expected values.
Check the following:
- Voltage at the density meter terminals exceeds 10 volts.
- The density input default value is set to zero (if a non-zero
value is set, the meter will use the default value).