Sequential gearbox indicators combine a set of electronics and highly accurate rotary potentiometer sensor fitted to the selector barrel. The action of the gearstick rotates this barrel to set a position corresponding to the selected gear. Fundamental to its working is the SRS280 which measures this position and allows the electrical control unit to calculate which gear is selected and displayed accordingly. This method of sensing the selected gear offers highly reliable and repeatable results, compared to microswitches to count the number of times the gearstick has been knocked forwards or backwards by the driver. With sequential transmissions becoming ever more popular in the motorsport arena, the SRS280 is proving to be the sensor of choice for motorsport professionals.
“I was initially attracted to the Penny + Giles sensors by the cost,” comments Neil Wallace, Managing Director, GearTronics. “There are few rotary position sensor manufacturers who offer such a reliable and accurate sensor at such a reasonable low price at the volumes I require. I have been able to reduce costs significantly and pass on those savings to customers, making our products an attractive choice for gearbox manufacturers and end-users alike.”
Designed for high reliability in extreme temperature, high vibration and shock environments, SRS280 offers a range of innovative features which overcome the shortcomings of competitive products and set a new standard of reliability for the industry. The rotary position sensors can also be used more widely in motorsport for example, the position monitoring in computerised control systems such as fuel control systems, suspension and steering monitoring.
The harsh conditions to which traditional sensors are routinely subjected commonly lead to problems with signal continuity as a result of broken casings, intermittent shaft contact or ingress of dust or fluids. Other complaints from the industry include inadequate sensitivity and lack of flexibility with mounting and connection options.
“A common complaint I was receiving from the gearbox manufacturers was that the potentiometers I used previously were unreliable, and lacked the physical robustness required in the field, with a tendency to fail prematurely,” says Mr. Wallace. “In choosing to use Penny + Giles’ sensors I have eliminated this problem and can now offer quality indicators at a reduced price.”
“We have conducted extensive research in Formula One and other motor racing markets to identify these issues and develop solutions,” says Mike Iles, Business Development Manager, Penny + Giles. “The SRS280 is based on Penny + Giles’ proven hybrid potentiometer track technology, which is widely used in linear position sensing systems all over the world. The technology is known for its stability in extreme environments, its virtually infinite resolution and its durability – in excess of 50 million operations.”
SRS280 was the first rotary sensor of its kind to offer a range of thirty-five different models with angles from 10 to 350 allowing the user to match the sensitivity of the system to the application, for better data acquisition and closer control.
The sensors are available with dust-proof and waterproof casings sealed to IP50 or IP66, and all versions have an integral moulded cable assembly which negates the need for a heat-shrink boot. Crush proof mounting flanges feature steel inserts which protect the casing from the possibility of damage from mounting bolts. As a result, SRS280 can be repositioned as many times as necessary, making it a much better investment than traditional designs which often have to be discarded after only one use.
The shaft has a unique double bearing support system that is designed to withstand the harsh vibration conditions of an automotive or motorsport environment, ensuring trouble-free operation with no signal loss. There is a choice of a D-shaped or ‘sprung ear’ shaft, both compatible with existing de-facto industry standards for straightforward interchangeability on existing equipment.
“Motor racing is a precision sport and the difference between winning and losing can be hundredths of a second,” says Mr Wallace. “SRS280 provides optimum product performance and reliability under the most extreme conditions. I have been thoroughly impressed with the results since using the sensor and plan to order more in the near future.”
