Detcon CXT-DM - Manual (Page 37)

Model CXT-DM
5. Service and Maintenance
Calibration Frequency
In most applications, monthly to quarterly span calibration intervals will assure reliable detection. However,
industrial environments differ. Upon initial installation and commissioning, close frequency tests should be
performed, weekly to monthly. Test results should be recorded and reviewed to determine a suitable
calibration interval.
Visual Inspection
The Sensor should be inspected annually:
• Inspect the sensor for signs of corrosion, pitting, and water damage.
• Remove the Splash Guard and inspected it for blockage, broken, cracked, or missing pieces.
• For H2S Sensor assemblies, inspect CXT-DM Series Splashguard Adapter Assembly with integral
filter (P/N 602-003552-100) for blockage of filter material.
• Inspect inside of the Junction Box for signs of water accumulation, signs of corrosion.
• Check wiring to ensure there are no loose or pinched wires and all connections are clean and tight.
Condensation Prevention Packet
A moisture condensation packet should be installed in every explosion proof Junction Box. The moisture
condensation prevention packet will prevent the internal volume of the J-Box from condensing and
accumulating moisture due to day-night humidity changes. This packet provides a critical function and should
be replaced annually. Detcon’s PN is 960-202200-000.
5.1 Replacement of the batteries/battery pact
5.1.1 Units with 12V Smart Battery Pack
The CXT-DM Sensor incorporates a ‘Low battery’ fault message which will appear as an alternating display
between the current gas reading and ‘VOLT’ on the sensor display. This fault will appear when the battery
voltage drops below 7.5 volts. When the voltages drops below 7.2 volts the display will change to a steady
‘VOLT’ display, the sensor will then enter into ‘Fault’ mode, and the sensor will no longer provide a valid gas
reading.
NOTE
The safety approvals require removing entire sensor assembly to a non-hazardous area
before installing or changing out the batteries or battery pack.
1. Remove the cover from the J-box.
2. Unscrew battery bracket lid, and swing the lid away from the battery pack.
3. Remove the battery pack from the J-box, and replace with new battery pack.
4. Swing the lid back over the battery pack, and re-tighten screws in battery bracket lid.
5. Replace the cover on the J-box.
5.1.2 Units with Tri ‘C’ sized Lithium Battery Holder
NOTE
The safety approvals require removing entire sensor assembly to a non-hazardous area
before installing or changing out the batteries or battery pack.
1. Remove the cover from the J-box
CXT-DM Instruction Manual Rev. 1.6 Page 33 of 52