Hach ORBISPHERE 366 Series, Basic User Manual

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• Power On
• Sensor Out
• Thermal Cut-off
• Alarm High
• Alarm Low
• Normal measurement
6.6.12 Sampling rate for the automatic storage mode
Choose the Configuration, Sampling Rate command to select the time interval (Acquisition rate) for
the automatic storage. This rate is used only when automatic storage mode is set to Timer (see
Automatic or manual storage mode on page 24).
Note: The Acquisition rate set via this menu is independent from the Monitoring chart updating rate. The Sampling
rate menu applies only to automatic storage mode, while the chart updating rate is used only for displaying real-
time results on the monitoring chart.
6.6.13 Locking the "CAL" key
Use the Configuration, Calibration Key Status command to prevent an accidental sensor calibration
via the instrument front panel. Choosing Disabled will lock out the "CAL" key on the instrument front
panel. To unlock, choose Enabled.
6.6.14 Setting alarm limits
To set the alarm limits choose Configuration, Alarms, Enter the Low and High gas concentration
limits and click OK to save the new limits.
When the measured gas concentration exceeds the high limit or falls below the low limit, the
instrument sends a signal at the alarm output connections. The instrument clears the High alarm
when the gas concentration drops to 1% below the high limit, or clears the Low alarm when the
concentration rises to 1% above the low limit.
6.6.15 Setting analog output limits
Use this command to specify the analog output range from the instrument. Enter a Low and High gas
concentration value to specify the limits for the analog output, corresponding to:
• 0 (Low) - 20 (High) mA
• 4 (Low) - 20 (High) mA
• 0 (Low) - 2 (High) Volts
6.6.16 Setting “Alarm on” analog output
Turn on this feature when the hardware of the instrument is configured for analog output from 0 to
20 mA. When this feature is enabled, the alarm information will use the range within 0 to 4 mA.
Analog output Explanation
1 mA On for 5 sec. at instrument start up
2 mA Sensor out, or unplugged
3 mA Thermal cut off function activated
Section 7 Calibration
7.1 Barometric pressure sensor calibration
Calibrate the internal barometric pressure sensor using a certified barometer and the ATEX
3660 software. Select “Troubleshooting / Pressure Calibration” to start the calibration procedure. A
warning message is displayed first. Choose OK to continue.
The calibration procedure displays a barometric pressure calibration window showing the actual
instrument pressure reading. Enter the current atmospheric pressure, in mbar, in the Calibration
Pressure box. Choose Calibrate to store the calibration value.
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