Text version of the page

MagLine – Magnetic length and angle measurement

10

Technical Details

Incremental systems: Reference signals of sensors and magnetic bands

1. 3. A A sensor with the code “0” sensor with the code “R/RB” (without index) is only equipped with one sensor element which measures length. A sensor version without index runs, for example, with MB500 incre- mental (one track). (one-time or periodical reference point) is equipped with an additional sensor element which scans a second track parallel to the first track on the band. MB500 (2 tracks) with reference point code E (once) or P (periodically) is used, for example, for this sen- sor. In addition the position of the reference signal on the band must be determined (refer to the data sheet of the re- spective magnetic band).
Diagram to sections 1./2. Diagram to sections 3. 2. A sensor with the code“I” (index signal) is also only equipped with one sensor element which measures length. With an additional electronic system an index signal is gen- erated by the sensor for each period. A second track on the band is not necessary to generate such a signal. This sensor type therefore also runs with MB500 incremental (one track).
If a sensor has the code I/O , it works with …MB code O (without reference point/1 trrack) sensor has the code R/RB , it works with …MB code

Magnetic length and angle measuring systems - 16025 .

E (single reference point/2 tracks)MB code

. 15

P (periodical reference point /2 tracks)

3 . 23 . 33

Options for referencing an incremental system

1. You are using a system comprising a sensor without reference signal and a magnetic band with one track 3. You are using a system comprising a sensor with the refer-ence signal “R/RB” and a magnetic band with two tracks (one-time/periodical reference point, magnetized on the second track)On this version an external encoder is normally not necessary, referencing is only performed with the reference signal of the sensor. Realignment can only be performed at the point at which a corresponding reference point is magnetized onto the band. With long measurement distances, it is recommended to work with periodical reference points if necessary and to identify these with external encoders. Referencing is performed with the repeat accuracy of the sensor (refer to the respective sensor data sheet).

. 43

The system can be either referenced by moving to a defined po-sition – e.g., a stop block - or by linking a certain position with an external encoder (limit switch, light barrier, etc.). Problem: Depending on the version of the stop block or the external en- coder, the repeat accuracy of this method is insucient. 2. You are using a system comprising a sensor with the index signal “I” and a magnetic band with one track

. 53

With this version you link an external encoder (limit switch, light barrier, etc.) with an index signal which the sensor emits with each magnetic period. The only function of the external encoder is to determine the correct period. The accuracy of referencing corresponds to the repeat accuracy of the sensor (refer to the respective sensor data sheet). The following must be observed: Referencing can be performed at any point of the traveling

. 6 3 3 . 7

Sensor with code I without reference point/1 trrack â–  path. The switching path of the external encoder must be shorter
â–  than that of the distance between the index pulses. Note: On the MB500 the index pulse distance is 5 mm, on the MB100 only 1 mm.
Sensor with codew R/RB with 1 or x reference point(s)/2 tracks If a 5 MagLine | 5.0 Product Overview www.siko.de