ABB CL Series, Руководство по применению

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Wiring with the display system
196
1SVC 440 795 M1100
High-speed incremental encoder counter
The display system provides two high-speed incremental
counters CI01 and CI02 for use. The high-speed counter
inputs are permanently connected to the digital inputs I1, I2,
I3 and I4. These counter relays allow you to count events
independently of the cycle time. You can enter upper and
lower threshold values as comparison values. The contacts
will switch according to the actual value. A CI… counter
allows you to define a start value if required.
The CI.. counters are not dependent on the cycle time.
Counter frequency and pulse shape
The maximum counter frequency is 3 kHz.
The signals must be square waves. The mark-to-space ratio
is 1:1. The signals of channels A and B must be offset by 90°.
Otherwise the count direction cannot be determined.
Wiring of a counter
The following assignment of the digital inputs apply:
• I1 count input for counter CI01 channel A
• I2 count input for counter CI01 channel B
• I3 count input for counter CI02 channel A
• I4 count input for counter CI02 channel B
h
Double the number of pulses are counted as a result of the
internal method of operation of the incremental counter.
The incremental counter evaluates the rising and falling
edges. This ensures that the pulse count is not affected by
oscillation of a signal edge. If the number of pulses are
required, divide the value by two.