Accuracy
How is system accuracy affected when the sensor is at scale's edge?
The sensor operates accross the whole measuring length of magnetic scale. However, at the scale's edges the system accuracy gets worse. Therefore, we recommend that the beginning of measuring length is at least 4 mm from scale's edges.
What is the accuracy of linear magnetic encoder systems and how is accuracy affected when measuring less than 10 mm of scale?
Scale accuracy is defined by multiple accuracy grades: ±40 µm/m, ±20 µm/m, ... The extreme values of measuring curves over any one-meter-section of measuring length lie within accuracy grade ±a. If measuring length is shorter than one meter, accuracy grade corresponds to this length.
Available accuracy grade | Products |
± 20 µm | LM10, LM13 |
± 40 µm | LM10, LM13, RoLin |
± 100 µm | LM15 |
What is the accuracy of linear magnetic encoder system for scale lengths of 2 m, 3 m, 4 m, etc.?
Our accuracy grade (a) corresponds to system accuracy over 1 m scale. For example:
a = ±20 µm
2 m scale length: 2 m × 20 µm = 40 µm
3 m scale length: 3 m × 20 µm = 60 µm
4 m scale length: 4 m × 20 µm = 80 µm
Which accuracy can be achieved with magnetic rings?
For more information click on link below:
Accuracy of ring encoder systems
What is the influence of ride height on system accuracy?
Influence of ride height on system accuracy is explained in the graph below:
Example: LM10 ride height influence on accuracy
What is the influence of temperature on system accuracy?
The linear expansion coefficient for MS scales is ~17 ppm or ~ 17 × 10-6/K. For each 1 degree Kelvin temperature change, the scale expands for 1 µm per meter.