Position and Speed Sensor MiniCoder GEL 2444
Main Features
- Metal casing
- Square-wave output
- Internal interpolations factor configurable ex works
Functional Description
- Measurement of speed and position by proximity sensing of precision target wheel
- Scanning by means of magnetoresistive sensor elements
- Measuring unit consisting of sensor and precision target wheel for installation on shafts with diameters ranging from 8 mm to more than 500 mm
Applications
- Speed detection in HSC spindles (High-Speed-Cutting)
- Measurement of speed and position of milling and grinding spindles in machine tools for the machining of metal, wood, glass, stone and aluminium
- Angle measurement in radar equipment
- Electronic synchronization of helical spindles in dry-running vaccum pumps
- Measurement of speed in test stands
Special features
- Sufficient scope for construction due to customerspecific production of precision target wheels
- Internal production of target wheels with module 0.3 and 0.5 from speeds from 0 to more than 70,000 min-1
- Cable outlet axial or radial
- Sensor fully encapsulated
- Very compact
Measuring Principle
- Integrated MR-sensors for contactless scanning of target wheel
- Sensor signals internally amplified and temperature compensated
- Frequency range from zero to max. 200 kHz
Output Signals
- Outputs short-circuit-proof
- Signal Forms:
- two square-wave signals offset by 90° and the corresponding inverse signals TTL / RS 422
- option: reference pulse
Technical data GEL 2444
Output level | TTL / RS 422 |
Output signals | two square-wave signals, by 90° out of phase, and their inverse signals short-cicuit-proof, option: reference pulse |
Output frequency | 0 to 200 kHz for CL = 5 nF |
Supply voltage VS | 5 V DC ± 5% |
Power consumption without load | ≤ 0.3 W |
Permissible air gap | 0.15 mm ± 0.02 mm with module 0.3 0.20 mm ± 0.03 mm with module 0.5 |
Width of target wheel | min 4.0 mm |
Material of target wheel | ferromagnetic steel |
Operating temperature range | -30 °C to +85 °C |
Ambient and storage temperature range | -40 °C to +120 °C |
Protection class | IP 68 |
Electromagnetic compatibility | EN 61000-6-1 to 4* |
Insulation strength according to EN 60439-1 | 500 V |
Vibration resistance (IEC 68-2-6) | 200 m/s2 |
Shock resistance (IEC 68-T2-27) | 2000 m/s2 |
Weight | 30 g |
Housing material | zinc diecasing |
Connection | 9-core cable, cross section 0.15 mm2, outside diameter 5 mm(-0.3), min. bending radius 25 mm |
The technical data provided are valid for the operating temperature range.
*) Important: Where possible, connections to the cable screen should be made coaxially. Connections to the cable screen using single wire cores should be kept as short as possible.
Dimensional drawing, Boring and milling diagram
Type code
T = Square-wave signal
N = reference mark (tab)
A metal tab integrated in the target wheel is detected when its position is exactly between two teeth. This reference signal can be used as a positon reference. This is required, for instance, for the automatic changing of a tool in a milling or grinding spindle.
M = reference mark (groove)
Depending on size and geometry of the target wheel, the target wheel version with a reference tab can only be used up to certain speeds. For speeds beyond 30.000 min-1, a MiniCoder detecting a reference groove integrated in the target wheel is used. For technical reasons, the target wheel is in this case composed of two parts.
Z = Reference mark (flag over groove)
This MiniCoder version can be used for scanning a target wheel manufactured in one piece. The system permits reaching speeds of more than 70.000 min-1. The reference tab is in alignment with a tooth of the pulse track.
_ = Internal multiplier
The new electronic module that has been used in the GEL 2444 MiniCoder enables the generated sin/cos signals to be interpolated directly. This means, for instance, that for a precision target wheel with 250 teeth, you have 5000 square wave pulses per revolution available (this is with factor D = 20; higher factors are available on request). This interpolation is carried out directly within the sensor. By using four-edge evaluation in the control electronic a resolution of up to 20,000 steps per revolution ist possible.
R = Radial cable outlet
3 = Module 0.3
The module describes the relation between the number of teeth and the outer diameter of a target wheel. The smaller the module the smaller the outer diameter for the same number of teeth. The air gap to be observed between sensor and target wheel is less with module 0.3 than with module 0.5.
da= m • (z+2)
da = outer diameter m = module z = number of teeth
The MiniCoder must be ordered compatible with the target wheel.
5 = Module 0.5
module | air gap d adjustment dimension |
distance tolerance |
0.3 | 0.15 | ± 0.02 mm |
0.5 | 0.20 | ± 0.03 mm |
Connection type K = cable end open
The Minicoders are manufactured with open cable end. The following cable length are available (30/150/250/600 cm).
Important: Fit the cable screening as coaxially to the earth cable as possible. When fitting the cable screening onto an earth cable, the earth cable should be run as short as possible.
_ _ _ = Cable length (cm)
For connection type K= cable end open, 4 cable length are
available: 30, 150, 250, 600 cm. For ready-made
connecting cables with male connectors, the length of the
cable is to specified in cm.
Cable type: PUR cable 9 x 0.15 mm2 screened
Screen not connected on MiniCoder side
Outside diameter: 5 mm (– 0.3)
Min. bending radius: 25 mm
This screen connection is connected to the screen of the sensor cable. In order to improve electromagnetic compatibility (EMC), the screen connection should be connected to the flange on which the MiniCoder is mounted.
Custom-made target wheels, Standard target wheels
Custom-made target wheelTarget wheel are made to individual specifications on request of the customer. Please send us a dimensional drawing of your target wheel (if possible, as a dxf-file) to [email protected].
Target WheelsFor detecting rotary movements, the MiniCoders and target wheels form a complete unit. The target wheel size and hence , its diameter are directly dependent on the module and the number of teeth, i.e.:
z = (da/ m) - 2da = m • (z+2)
Standard target wheels (see table) are available at short notice ex factory.
Table - standard target wheels
Number of teeth z |
module m [mm] |
OD - Θ da [mm] |
ID - Θ standard [mm] |
ID - Θ di max. [mm] |
collar - Θ dr [mm] |
100 | 0.5 | 51.0 | 12 H7 | 30 H7 | 47 |
125 | 0.5 | 63.5 | 12 H7 | 35 H7 | 60 |
128 | 0.5 | 65.0 | 12 H7 | 35 H7 | 61 |
200 | 0.5 | 101.0 | 12 H7 | 70 H7 | 97 |
250 | 0.3 | 75.6 | 12 H7 | 45 H7 | 72 |
250 | 0.5 | 126 | 25 H7 | 85 H7 | 122 |
256 | 0.3 | 77.4 | 12 H7 | 50 H7 | 74 |
256 | 0.5 | 129 | 25 H7 | 90 H7 | 125 |
360 | 0.3 | 108.6 | 25 H7 | 70 H7 | 105 |
500 | 0.3 | 150.6 | 25 H7 | 110 H7 | 147 |
512 | 0.3 | 154.2 | 25 H7 | 110 H7 | 151 |
Type code for standard target wheels