New 4OXV oxygen sensor moves reliability, stability and performance to a new level

If you manufacture oxygen detectors, you need to know about 4OXV, a new oxygen sensor set to revolutionise the gas detection industry. Launched by City Technology, it overcomes the single biggest headache for instrument manufacturers, sensor lifetime. Unique vented technology within the 4OXV and other significant design enhancements address this issue head on, reducing lead exhaustion, electrolyte leakage and inappropriate response to environmental variability – the three main causes of oxygen sensor premature failure. The 4OXV eliminates the most common sources of early life failure: false alarms, premature failure and steady state or transient interactions with the environment.

Elimination of false alarms

To avoid a false output, control of any potential pressure gradient across the sensing electrode to negate the effects of rapid temperature changes is the most critical factor affecting the linearity of the output. In the 4OXV, the pressure equalising vent design equilibrates the sensor during pressure or temperature transients, eliminating false alarm glitches. An internal anti-bulkflow mechanism eliminates false alarms and further dampens the response to transient pressure changes. The design also minimises threshold drift in slow temperature and pressure variations, providing the maximum possible headroom between the quiescent state and alarm outputs. More than 1000 sensors, both new and artificially aged to the equivalent of 24 months life, have been tested under strenuous conditions with no glitches observed. Humidity changes are another significant cause of false alarms. 4OXV features an integrated moisture protection membrane to prevent the ingress of humid air into the chamber.

Lead exhaustion

By the nature of the electrochemical reaction upon which the sensor’s operation is based, the lead anode is oxidised over time. The anode assembly in 4OXV has a fused base, guaranteeing connectivity with all the lead strands from which it is made and the current collector is deeply embedded in the structure, ensuring good connectivity with the output pin. The anode’s design ensures that lead exhaustion will not occur prematurely before the end of the sensor’s 24-month life.

Electrolyte leakage

The 4OXV has improved pin retention and O-ring sealing to prevent electrolyte leakage. It also has enhanced sealing between the internal membrane upon which the catalyst is mounted and the liquid electrolyte, preventing seepage into the internal plenum chamber and possible blockage of the input capillary. Internal electrolyte leakage will potentially cause the instrument to fail because air cannot enter through the capillary. External leakage where electrolyte seeps though the seals between the pins and the unit’s body can, apart from the obvious failure of the sensor itself, result in irreparable damage to the instrument’s PCB.

The dawn of a new era in oxygen sensing

The 4OXV sensor is the result of a five year, multi-million dollar, multi-disciplinary development programme, involving a 20+ strong team of scientists and engineers and more than 9500 hours of extended testing. 4OXV consigns the problems of false alarms and premature device failures to history - a major advancement for the life safety industry. Instrument manufacturers can now offer users unparalleled confidence in the detector’s stability, performance and freedom from false alarms, reducing their costs and reinforcing trust in gas detection technology.