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Linear Scale Gel 177
Linear Scale Gel 177
General Information
The rugged linear scale GEL 177 - made of aluminium extruded profile - was conceived for the machine construction industry. The position sensing is performed contactless by means of permanent magnets of various designs.
- An open magnet is directly mounted to the moving machine part. It runs contactless over the profile housing.
- A position slide with magnets runs on profiled rails in the housing. It is connected to the moving machine part with a ball-shaped coupling.
This linear scale offers the user the following important advantages:
- a long service life due to the non-contacting and wearless measuring of position magnets
- direct, digital synchronous serial ouputs (SSI) or analogue current or voltage ouput
- there is a homogeneous supply voltage of 24 V
- for lengths up to 5,000 mm
- resolution up to 5 µm (SSI)
Output Signals
The absolute information on the travelled path is supplied either digitally or analogue. The digital transmission is performed in Gray-Code, so that a simple cabling is ensured and the transmission security rises. Various current/voltage outputs are available as analogue output signals.
Measuring principles
The tried and tested measuring principle was further improved. It is the running time of the torsion pulse that is measured and which is proportional to the distance between an internal start signal and a stop signal. The torsion emerges from the interaction of two magnetic fields under the position magnet. The running time is the absolute measure up to the position of the magnet and is transformed into a digital or analogue output signal.
Technical Data
| Sensor | Analogue | SSI |
| sensor head | aluminium die casting | |
| scale | aluminium extruded profile | |
| protection class | IP 65 | |
| fastening | with movable mounting feet | |
| connection type | plug or cable connection | |
| measuring length | 50 ... 5,000 mm in 50 mm steps (special lengths in 5 mm steps) | |
| resolution | 25 µm or 16 Bit | 5 µm |
| linear tolerance (non-corrected) | < ± 0.02 %*, min. ± 50 µm (independent of influences of temperature from outside) | < ± 0.01 %*, min. ± 40 µm (independent of influences of temperature from outside) |
| repeatability | < ± 0,001 %*, min. ± 2,5 µm | |
| hysteresis | < 4 µm | |
| voltage supply | 24 V DC (+20 % /-15%) | |
| power consumption | 100 mA typ. | 70 mA typ. |
| temperature coefficient | < 40 ppm/°C | < 15 ppm/°C |
| voltage sustaining capability | 500 V | |
| operating temperature | -40 °C ... +75 °C | |
| EMC (if the assembly instructions are observed) | ||
| electromagnetic emissions | EN 50081-1 | |
| electromagnetic immunity | EN 50082-2 | |
| shock protection | 100 g (single shock) as per IEC 68-2-27 | |
| The linear scale GEL 177 is in strict conformity with Directive EMC 89/336/EEC of the European Union which is certified by the CE mark. | ||
| shock protection | 100 g (single shock) as per IEC 68-2-27 | |
| vibration protection | 5 g /10 ... 150 Hz as per IEC 68-2-6 | |
| SSI | ||
| data format | - | Gray |
| data length | - | 25 bits |
| output signal | ||
| voltage | 0 ... + 10 V or + 10 ... 0 V, RL≥ 5 kΩ | - |
| current | 0 ... +20 mA or +20 ... 0 mA 4 ... +20 mA or +20 ... 4 mA burden 0 ... 500 Ω |
- |
* referring to the measuring length
Synchronous serial interface, Pin layouts
Synchronous serial interface
Number of distance measurements per second
| measuring length | 150 | 300 | 500 | 750 | 1000 | 2000 |
| measurements | 10000 | 6600 | 4500 | 3300 | 2500 | 1400 |
Baud Rate
The transmission rate depends on the line length and reaches a maximum of 1.5 MBaud. Use screened cables with paired wires.
| Cable Length | <50 | <100 | <200 | <400 |
| clock frequency [kHz] | <400 | <300 | <200 | <100 |
Pin Layout (analogue)
6-pole plug or cable outlet
Pin Layout (SSI)
7-pole plug or cable outlet
Dimensioned drawings, Type code
Dimension Drawing
Type code
