New products:

 TEL1-PCM
Single-Channel Telemetry System

General Description
The TEL1-PCM single-channel telemetry system offers the easiest handling for the wireless transmission of strain gage signals from rotating shafts. The very small encoder 35 x 18 x 12 mm with a weight of 13g. The transmitter (encoder) part is simply mounted on the rotating shaft with a special fiber reinforced tape. Powering of the transmission part and the digital data transfer between transmitter and receiver is realized inductively.

Functional Description
The TEL1-PCM transmitter provides a pulse code modulated signal (PCM) to an induction winding around the shaft (max. diameter 500mm, other on request!). The magnetic field of this winding enables the inductive transmission of the signal to the pickup coil. From there the signal is transferred by cable (5 m) to the receiver. The maximum distance between the transmitter coil and the pickup is 20mm. (with standard head)

The receiver unit offers a BNC connector at the front panel with analog outputs ± 10 V and a optional a digital output for PCM interface ECIA100 (for notebooks) or IF16 (PCI Desktop). An LED bar indicator shows the actual level and a successful Auto Zero calibration. Overload is indicated by the last LED´s in pos. or neg. direction of the bar graph. These OVL-LED´s operate in peak-hold mode and are reset by pressing the overload switch.

Strain gage sensors (>350 Ohm) in full- and half- bridge configuration can be directly connected to the transmitter. The excitation is fixed to 4 Volt DC and the gain is set by the gain switch on the receiver side. An auto-zero (AZ) adjustment is executed by pressing the AZ button on the front side of the receiver. The successful AZ operation is indicated by a yellow LED in the middle of the LED bar indicator. When the AZ completes the LED continuously illuminates. A continued flashing of the yellow LED indicates some error in the AZ electronics. In this case please contact the support of KMT. Additional to the AZ you have the possibility to calibrate the bridge by external shunt. (+ and -). The AZ setting is stored in a Flash-RAM and thus is not lost during power-off. Use only shielded sensor cable.

CT4 Wheel
Wheel Telemetry system

CT4/8-Wheel is an telemetry system designed for easy mounting onto rotating Wheels to provide non-contact transmission of measured parameters such as pressure, force, temperature, acceleration and voltage.

Sensors inputs are connected via screw on, waterproof connectors. Measured values are prepared in analog format, digitized and transmitted via radio frequencies. Four different carrier frequencies are provided, this allows up to four systems (e.g. for four wheels) to operate in parallel. The complete transmitter assembly is waterproofed to IP65 specifications.

The following sensors can be connected to the system: (STG) Strain gages sensors in full-, half- and quarter-bridge configuration (350 ohm or greater), Type K Thermocouples to 1000°C, ICP and capacitive sensors. Voltage inputs of +/-5V and +/-10V are available.

The measured values are processed and output as +/-5V analog signals at the BNC sockets (optional digital output for special PCM interface into a PC) on the stationary receiver located in a vehicle or helicopter cabin.

Resolution of 12 bits is standard; this enables an amplitude dynamic of 72 dB. The analog signal bandwidth is 0-95 Hz (-6dB) when configured as an eight channel unit. The measurement accuracy is +/-0.5 % (without sensor). The CT4/8-Wheel is suited for operation at ambient temperatures of -20 to +70°C. The transmission distance between transmitter and receiving antenna is of the order of 10m (30 feet) - depend of application!

 RPM8000PRO
Offers a discerning solution for automotive RPM measurement
without an additional sensor

RPM-8000-PRO offers a discerning solution for automotive RPM measurement without an additional sensor: the practical instrument is simply connected via a standard jack to the cigarette lighter socket and the RPM is shown directly on the LCD display. You even have the choice to output the data as an analogue voltage (1 Volt per 1000 rev/min) or as a digital pulse sequence (TTL). The smart measuring principle is based on an analysis of the ripple balance of the supply system, characteristic for all automotive dynamos and alternators. The frequency of this ripple amounts to about 100 to 120 pulses per engine rotation and delivers therefore good dynamic measuring results.

Though the frequency is proportional to the engine RPM, it also depends on the gear transmission ratio from crankshaft/generator and on the number of generator poles and phases. This makes the calibration of the input signal to the actual measured RPM necessary. The latest version of the RPM-8000-PRO now offers two elegant options:

• Internal calibration: The internal calibration presumes a stationary engine RPM of 2000 rev/min, which can be monitored by the automotive tachometer. By pushing the “Cal. Int” button the calibration starts, whereby the instrument assigns the actual measured pulse frequency to speed “2000” and outputs the actual engine RPM to the LCD display.

• External calibration (option): A laser RPM ”RPM-LASER-CAL” is needed for this option. A reflector tag is mounted on the crankshaft and scanned by laser beam. The TTL output of the laser instrument is connected via cable to the “Ext. Cal In.” input of the RPM-8000-PRO and delivers one pulse per rotation. By comparing the pulse sequence with the measured pulse frequency, the instrument calculates automatically the relationship between ripple balance and speed. Identical displays on laser and RPM-8000-PRO signal successful calibration (also shown by luminescent LEDs).

The measuring range of the analogue output can be varied on demand via jumpers (e.g. to 0.5, 1.0 or 2.0 Volt per 1000 rev/min). The TTL output can also be scaled with a frequency factor of 1:8 or 1:16 – and therefore adapted to the resolution ability of attached measuring systems. For testing purposes this “factor” between speed and TTL frequency can be output, instead of the speed, to the LCD display by pushing the “TTL” button. The instrument saves the calculated calibration data in non-volatile memory until the next calibration.

For more information see PDF data sheet

Data sheet