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6.1.3. Troubleshooting
sensor
problems
6.1.3.1 Can’t make a “One Button” automatic fresh air
adjustment
Possible causes:
1. The atmosphere in which the instrument is located is
contaminated (or was contaminated at the time the
instrument was last zeroed).
2. A new sensor has just been installed
3. Instrument has been dropped or banged since last turned
on.
Solution:
Take the instrument to fresh air and allow readings to stabilize.
Do a manual fresh air zero adjustment using buttons on the
instrument keypad as discussed in section 4.6.1.
6.1.4 Sensor
caps
Part Number
Description
54-26-0990
Oxygen Sensor Cap
54-26-0981
LEL Sensor Cap
54-26-0914
‘Duo–Tox’ Sensor
Cap
54-26-0901
CO / CO+ Sensor
Cap
54-26-0902 H
2
S Sensor Cap
54-26-0903 SO
2
Sensor Cap
6.2 Internal motorized pump
Every Cannonball3 includes a built-in continuous sample draw
pump. Since the Cannonball3’s sensor compartment is
contained within the instrument, the gas sample must be drawn
into the instrument by the pump through a probe assembly that
is attached to the inlet coupling on the front of the unit.
The sample draw pump includes a pressure sensor designed
to protect the Cannonball3 from exposure to water or other
liquids. If there is a change in pressure in the sample draw
assembly due to fluid intake, the pump immediately shuts
down. After a few seconds audible and visual alarms
indicating a low flow condition will also be activated.
CAUTION: The sample probe and hose assembly must be
attached to the sample draw inlet coupling for the
Cannonball3 to operate properly. Failure to attach the
sample probe assembly may result in damage to the
instrument.
Procedures for proper use of the motorized sample pump are
contained in Chapter 2.
The pressure sensor in the sample draw pump is designed to
detect changes while the sample-draw probe is being held in a
vertical position. If the probe is held horizontally or at a low
angle when inserted into a fluid, a pressure drop sufficient to
cause the pump to shut down may not be generated, and
water could be drawn into the instrument. To avoid potential
damage, care must be taken to keep the probe vertical any
time fluids might be present.
As an additional safeguard, the pump also contains an
internally housed particulate filter. If the pump is operated in a
particularly dirty atmosphere, the internal filter can become
clogged and will require periodic replacement.
Figure 6.2 Bottom side of lower case assembly
6.2.1 Pump
replacement
To replace the pump module, simply loosen the two pump
module retention screws on the bottom of the lower case
assembly and remove the pump module from the instrument.
Install the new pump module, tighten the retention screws and
restart the instrument.
CAUTION: Be sure to properly seat the o-ring on the base
of the new pump module before installation. Failure to
seat the o-ring will compromise the Cannonball3’s
resistance to water and dust and may result in instrument
damage.
6.2.2
Internal filter replacement
The internal filter assembly is located at the front of the
Cannonball3 and is retained by a single screw. To replace the
filters, simply remove the retention screw, replace the filters
and reinstall the retention screw.
6.2.3
Pump failure at start up
Pump seals are automatically tested by the Cannonball3
during the start-up sequence.
Sample Pump Test
Block End of Sample Probe
Pump Test Failed
Remove Blockage and Retest
Summary of Contents for Cannonball3
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