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Renata S.A.

Tire Pressure Monitoring Systems

We all need something to get us going

RENATA Batteries (the SWISS Power source) in the right place (TPMS) allows to run the system properly

Thanks for the good timing, forward thinking and a little legislative intervention, RENATA is about to hit it big. In summer 2002 Federal regulators at National Highway Traffic Safety Administration (NHTSA) in the Department of Transportation formally issued a new rule mandating new vehicles have to include electronic tire pressure monitors as standard equipment.

RENATA has been working in this field since 1997. The direct systems use a sensor and a battery powered RF transmitter that sends tire pressure data to a control unit in the car. RENATA Batteries has been first in Chevrolet Corvette, a General Motor car in the 1997 model year. But in all, fewer than 35'000 vehicles have been equipped in this manner.

During 2002, the relatively new market for Tire Pressure Monitoring System reaches about 5-6 million units worldwide. This figure will grow to 10 million units in 2003. For the first few years, RENATA owned 100 % of the original equipment market, but other players have arrived since.

RENATA S.A., a company of the Swatch Group Ltd, Bienne / Switzerland, was founded in 1952 as a manufacturer of mechanical watch parts. From 1976 onwards and within just a few years, the company was transformed into one of the leading producers of miniature batteries (button cells) for watches and other electronic products. The activities in this field started with mercury and silver oxide batteries. 3 V lithium coin cells followed from 1983. Zinc-air batteries were launched in 1995. As its latest activity, RENATA S.A. began producing rechargeable lithium ion batteries in May 2000.

Five good reasons, why RENATA Batteries:

  • Made in Switzerland (Quality/process/Support) SWISS QUALITY
  • Flexibility (short delivery time, reliable partner for Design In, Technical support)
  • Consistent Performance, long life and reliability as well as an excellent engineering support
  • Provide compact and complete solutions (tabbed batteries, high precision)
  • quick prototyping

So called direct TPMS's, battery driven, have several advantages and disadvantages: Following the main battery dependent features:

Advantages:

First, direct TPMS's actually measure the pressure in each tire, they are able to detect when any tire or combination of tires are under-inflated, including when all four of the vehicle's tires are equally under-inflated.

Second, since most direct TPMS's are battery-operated, they can operate while the vehicle is stationary. Thus, if a vehicle's tire becomes significantly under-inflated while the vehicle is parked, a direct TPMS can alert the driver as soon as the relevant person starts the vehicle. The battery is a key issue in such a system! Renata batteries full fill a wide temperature range (-40°C to 150°C).

Third, direct TPMS's have a high sensibility and can detect small pressure losses. Some systems can detect a drop in pressure as small as 1 psi.

Fourth, direct TPMS's can be linked to a display that tells the driver which tire is under-inflated and the actual pressure in each tire.

Fifth, direct TPMS's will not give false positives if the vehicle is being driven on gravel or bumpy roads, or has mismatched tires or a tire that is out of balance or out of alignment.

Disadvantages:

First, the direct TPMS's are more expensive than indirect TPMS's for vehicles already equipped with ABS.

Second, the wheel components of direct TPMS's are less robust and more likely to sustain damage than the wheel components of indirect TPMS's, especially when tires are taken off the rim. The service station notes, however, that it has not received any information indicating that direct TPMS's have sustained damage during driving or tire service. The service station requests comments on the likelihood of such damage.

Third, most direct TPMS's need an independent power source. Those that do are powered by batteries, which generally have a life span of five to ten years. This also means that unless a direct TPMS's is equipped with a low battery warning indicator, the driver might not know when the batteries come to the end of its life. The life span of the battery depends on several parameters:

Therefore: Battery life itself is one element, which depends on the chemical and technical concept. TPMS life as a system is the other element. Too high pulses and too high current demand shorten the life span of a battery dramatically.

Renata S.A.

RENATA S.A.,
CH-4452 Itingen
Switzerland

Tel. +41 61 975 75 75
Fax +41 61 975 75 95
sales@renata.com
www.renata.com