Omron CK3M Series, Hardware User Manual

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Encoder A+/B+ Encoder A-/B- Encoder loss detection
H L Normal
L H Normal
H H Detects loss
L L Detects loss
If loss is detected, the value of Gate3[i].Chan[j].LossStatus becomes 1.
Motor[x].EncLossCount adds 1 to the count when encoder loss is detected, and subtracts 1 when en-
coder loss is not detected.
However, the minimum value of
Motor[x].EncLossCount is 0, and it will never become a negative val-
ue.
You can set the motor to stop if
Motor[x].EncLossCount exceeds the value set in the
Motor[x].EncLossLimit . However, in a pulse input state, mis-detection of encoder loss may occur.
Therefore, when you use the function to stop the motor at encoder loss, take the possibility of mis-
detection during pulse input into consideration, and set the
Motor[x].EncLossLimit register to 40 or
more.
Precautions for Correct Use
If the digital quadrature encoder is used with single-ended input, you cannot use encoder loss
detection since the encoder loss may be detected even if the encoder is connected correctly.
Encoder Loss Detection in Sinusoidal Encoder
Normally, the sum of SIN squared and COS squared is always a constant value.
The sinusoidal encoder detects encoder loss by checking the sum of SIN squared and COS squared.
If loss is detected, the value of Gate3[i].Chan[j].SosError becomes 1.
3-3-7
Pulse Input Timing Specifications for Digital Quadrature Encod-
er
There are two types of input methods, differential input and single-ended input, for the digital quadra-
ture encoder.
The respective pulse input timing specifications are given below.
3 Configuration Units
3-23
CK3M-series Programmable Multi-Axis Controller User's Manual Hardware (O036)
3-3 Axis Interface Unit
3
3-3-7
Pulse Input T
iming Specifications for Digital Quadrature Encoder