Tyre pressure sensor meets US legal requirements

Edited by the Engineeringtalk editorial team Apr 2, 2004

A novel low-cost tyre pressure sensor uses proprietary, field proven technology that meets the requirements of the US Congressional TREAD (Tyre Recall Enhanced Accountability and Documentation) Act.

A novel low-cost tyre pressure sensor uses proprietary, field proven technology that meets the requirements of the US Congressional TREAD (Tyre Recall Enhanced Accountability and Documentation) Act.

After several years of fatal rollover accidents that were traced to improper tyre inflation, the US Congress passed the TREAD Act to protect the general public from future incidents.

One of the requirements of the US Congressional TREAD Act is to mandate vehicle manufacturers to develop technology for warning drivers of low and dangerous tyre pressures.

Automotive suppliers are moving quickly to get tyre pressure systems designed, tested and installed on new cars and trucks.

In Europe, most vehicles have this facility, and it is becoming increasingly required although not mandated.

"GE continues to be focused on delivering new sensor products into the automotive industry", said Kermit B Hoffman, President of GE Thermometrics.

"By combining the sensor and the compensating electronics into a single assembly, the GE now offers our customers a smaller sized element, with greater battery life and better value than separate discrete components".

"Furthermore, we are pleased to be providing drivers the next generation of tyre pressure technology and peace of mind as they travel".

The GE NPX sensor is a component within the pressure sensor module in each of the car tyres.

A radio frequency links the car tyre sensors to a dashboard display.

This method of tyre pressure measurement has been shown to be more accurate than competing techniques.

In addition, the pressure sensor is controlled by an internal program, which can turn off the sensor to conserve power, and thereby extending battery life.

The GE NPX is designed for Tier 1 and Tier 2 automotive suppliers who design and manufacture RTPM systems.

GE's NPX device minimises time to market because GE performs all the calibration.

The OEM supplier can now read the tyre pressure as a digital output from the GE NPX and warn the driver when a low tyre pressure condition occurs.

The GE NPX meets or exceeds the US Congressional TREAD Act specification for accuracy.

The NPX is delivered as a fully calibrated and programmed pressure transducer and is integrated into the module by the Tier 1 supplier where the automotive supplier adds its own program, a battery and a transmitter chip.

GE will incorporate customer-specific software onboard to provide programming that controls the inputs, manages the operation, and specifies the data output format.

The vehicle manufacturer mounts the component in the car tyre and installs the base receiver unit.

The GE NPX uses the same field-proven pressure-sensing element that can be found in GE's NPP sensor.

The NPP represents the first generation of RTPM sensors, which provided a low-level millivolt output.

The sensor's lightweight and small size are ideal characteristics for a reliable device that will be rotating with a car tyre at the equivalent of 2000g.

The NPP uses a QS-9000 quality system and over 10 million devices have been shipped to date.