Product category:
Temperature sensors
News Release from: Micro-Epsilon UK | Subject: EddyNCDT Series DZ130
Edited by the Engineeringtalk Editorial
Team on 28 February 2005
Eddy current sensor counts revs for
turbos
A miniature eddy current sensor system is helping leading manufacturers of turbochargers monitor the speed of turbocharger units up to 400,000rev/min.
A miniature eddy current sensor system is helping leading manufacturers of turbochargers monitor the speed of turbocharger units up to 400,000rev/min End user automotive companies such as Ford, Land Rover, Bentley and Jaguar are also using the sensors to map engine performance in test cells
Micro-Epsilon's system, the eddyNCDT Series DZ130, is a specially designed eddy current sensor system for revolution counting that incorporates a compact design controller with analogue and digital output, plus a miniature sensor with a diameter of 3mm.
No rotor modification is necessary and the system can be used for any turbocharger with metallic rotor blades.
Automotive suppliers are constantly striving to develop smaller, more compact turbocharger units for their customers and Micro-Epsilon's eddy current sensor system is proving to be an ideal choice.
Gary Picken, Engine Test Supervisor at Honeywell Turbocharger Technologies, a manufacturer of turbochargers based in Skelmersdale, commented: "We've been using the sensor for about four years now for our range of Honeywell-Garrett turbochargers".
"Our automotive clients want ever-smaller turbochargers on their engines so we have to try to develop smaller units for them".
"We selected Micro-Epsilon's sensor because of its small diameter and because it is easy to fit and easy to changeover when testing different sized turbochargers".
"We're measuring speeds up to around 300,000rev/min and have had no reliability problems and the system is very accurate".
On the end user side, Stuart Bell, Powertrain Development Engineer at Land Rover, is using Micro-Epsilon's sensor system to measure turbocharger speed on Land Rover vehicles.
He explained: "We use Micro-Epsilon's NCDT sensor system on our complete range of Land Rover vehicles for in-vehicle testing".
"We chose the sensor primarily because of its accuracy, reliability and ability to withstand harsh temperature conditions".
"Recently, we've used the system on the Land Rover Discovery 3 vehicle for transient tests, where we can dynamically test the turbocharger with different loads and speeds".
"We also check the durability, surge and best airflow paths".
The sensor works on the eddy current measurement principle.
A coil is potted in a sensor case and is energised by a high frequency alternating current.
The electromagnetic field from the coil generates eddy currents in the turbocharger blade.
Every blade generates a pulse and the controller identifies the speed by considering the number of blades.
The system is optimised for mobile and stationary use in test and R and D operations.
Adjustment and set up of the sensor is straightforward due to a status LED.
The extensive length of the sensor cable (6m) and the different signal outputs guarantee flexibility for the application.
Because of its immunity to oil, dirt, dust, moisture and interference fields, the eddy current principle is ideally suited for applications in harsh industrial environments.
The sensor can operate in temperatures from -40 to +150C on a 9 to 30V DC power supply.
Maximum speed range is 400,000rev/min and the maximum sensor to blade distance is 0.5mm.
According to Chris Jones, UK MD at Micro-Epsilon: "The sensor system has proved to be a huge success with the turbocharger manufacturers".
"As far as we know, it's the only turbocharger sensor system in the world that uses an eddy current sensor".
"Previously, turbocharger companies and end users such as Land Rover had to extend the compressor shaft and place a magnet on the end and measure speeds using a frequency counter, but this was unreliable".
"Our solution is more accurate, reliable and can handle much higher fan speeds". Request a free brochure from Micro-Epsilon UK ...
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