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Chapter 6. Basic maintenance
CAUTION: Maintenance in the Cannonball3 should only
be performed by appropriately trained personnel.
6.1 Sensors
The Cannonball3 is designed to recognize the “Smart Sensors”
that are currently installed and automatically set the
appropriate alarm settings and display readings. The
Cannonball3 also automatically recognizes when changes
have been made to the sensors installed since the instrument
was last turned on.
Note: Any changes made to the sensors installed, even
changing one sensor for another of the exact same type
will trigger a “Needs Cal” message the next time the
instrument is turned on. The Cannonball3 must be re-
calibrated before being returned to service any time
changes are made to the sensors installed.
Caution: The Cannonball3 must be turned off prior to
removing or replacing sensors.
6.1.1 Sensor
replacement
To remove or replace sensors in the Cannonball3, do the
following:
1. Make sure the Cannonball3 is turned off.
2. Remove the battery pack.
3. Remove the six Philip’s head screws from the bottom of
the instrument and separate the upper and lower case
assemblies. Take special care not to disconnect any of
the hoses connecting the sensor compartment, pump and
inlet fittings. In the event of a hose disconnection, see
figure 6.2.3 below.
4. Remove the two screws from the top of the sensor
compartment.
5. Lift up the sensor compartment cover to expose the
sensors.
6. Identify the sensor that you wish to replace and gently pull
the sensor out of its socket.
7. Press the replacement sensor into place. If a sensor cap
has been provided with the replacement sensor, discard
the sensor cap.
8. Replace the sensor compartment cover and secure with
two screws removed in step 4.
9. Rejoin the upper and lower case assemblies and secure
with the six screws removed in step 3.
10. The new sensor must be allowed to stabilize prior to use.
The following chart gives a breakdown by sensor type with
the required stabilization period for current Cannonball3
sensors.
Sensor
Stabilization Period
Oxygen (54-25-90)
1 hour
LEL (54-25-80(all versions))
5 minutes
All Toxic sensors except
those shown below
15 minutes
54-25-04 NH
3
Sensor
24 hours
The instrument does not need to be turned on while new
sensors are stabilizing, but functioning batteries must be
installed in the instrument. If the instrument is a NiMH
unit, a powered charger should be attached to the
instrument for the duration of the stabilization period.
11. The Cannonball3 will automatically recognize the changes
that have been made upon turn on and display the “Warning
Needs Cal” message.
12. Recalibrate the Cannonball3 with calibration gas
appropriate for the new sensor before the instrument is put
back into service.
Figure 6.1.1 Internal assembly diagram
Cannonball3 programming includes safeguards to recognize
maladjusted sensors. If the settings on the new sensor are
significantly different from those of the old sensor, a message
will be displayed indicating that that the sensor reading is “Too
Low” or “Too High” for One-Button-Auto-Calibration
adjustment.
Once the new sensor has been fresh air adjusted using the
“manual” calibration procedure, it will then be possible to do
subsequent fresh air and span calibrations by pressing the
MODE button to initiate the One-Button-Auto-Calibration
procedures.
Note: The first fresh air adjustment after installation of a
new sensor should be done using the manual calibration
procedure as discussed in section 4.6.1 of this manual.
6.1.2 New
sensor
releases
From time to time Sperian Instrumentation may release a new
type of sensor, or make changes to existing sensors in order to
improve performance. In some cases it may be necessary to
make changes to the Cannonball3’s internal instrument
software before making use of the new sensor. If a sensor that
is incompatible with the current configuration of the
instrument’s internal software is installed, a message stating
that the sensor is “Not Supported” will be displayed at the time
the instrument is turned on. Please contact the Sperian
Instrument Service Center at (860) 344-1079 for an
explanation of the required modifications.
Summary of Contents for Cannonball3
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