Lenord+Bauer GEL 211CS0, Руководство по эксплуатации

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Glossary Bauer
130 GEL 211CS0
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Glossary
SIN/COS signals
What are the SIN/COS signals?
Every MiniCODER provides two analogue signals with 90° phase offset: sine and
cosine. They represent the main signals for speed and incremental position regu-
lation. It is also possible to determine the direction of rotation using the two sig-
nals.
Each SIN/COS period represents exactly one tooth on the measuring scale with
the maximum voltage at the tip of the tooth and the minimum voltage in the gap
between the teeth.
What should the SIN/COS signals look like?
Ideal SIN/COS signals have an amplitude of Vpp = 1 V (peak-peak value). The
amplitude synchronism is a further quality criterion. This value represents the am-
plitude difference between the SIN and COS signal and should be kept as low as
possible:
Δ
Vpp
≈
0 V.
Along with the amplitude, the offset on the SIN/COS signals is important. An ideal
system has an offset of almost 0 V.
The final quality criterion is the phase error between the two signals. It should be
as low as possible:
Δφ≈
0°.
All the parameters listed here represent idealised values. Real applications will al-
ways vary from this value – however the differences should be kept as low as pos-
sible to obtain good signal quality.
What affects the SIN/COS signals?
The signals are primarily affected by the distance from the MiniCODER to the
target wheel (air gap): larger distances result in a lower differential amplitude and
vice versa. Minor deviations on the MiniCODER plus can be compensated using
the GEL 211C. All MiniCODERs are calibrated at Bauer to the module-
specific nominal distance.
A further factor that affects the signal quality is the quality of the measuring scale
(target wheel). Messy or inaccurate teeth as well as a concentricity error will result
in a low quality signal, especially in relation to the parameter Vpp.
The position of the sensor in relation to the target wheel (alignment) also affects
the SIN/COS signals. It must be ensured that the sensor is aligned correctly in re-
lation to the target wheel both horizontally and tangentially. Mounting inaccuracies
in this area will primarily result in zero offsets (offset errors).
Reference signal
What is the reference signal?
Along with the SIN/COS signals, an appropriately equipped MiniCODER will out-
put a reference signal once per revolution.