High Speed Inputs
Many machine control applications require various types of simple high-speed monitoring and control. These applications usually involve some type of motion control, or high-speed interrupts for time-critical events. The Rievtech Micro PLC solves this traditionally expensive problem with built-in CPU enhancements. High Speed Inputs The counting frequency of an ordinary PLC’s inputs can only reach tens of Hz. If the frequency of the input signal is higher than that, it is necessary to utilize high-speed inputs and high-speed counters (HSC), otherwise loss or errors in counting may occur. All DC models (except PR-6DC-DA-R and PR-12DC-DA-R-E) have 4 built-in high-speed inputs which can count pulses at a maximum rate of 60kHz for a single phase. This allows direct connection with a rotary encoder and counting input from the encoder. The Micro PLC can be used for various applications, such as speed measurement and high speed interval counting; by utilizing the input capture functions.
The encoder output pulse can be input to the high-speed counter to control such a high-speed operation.
Control an inverter by entering positional information with an encoder. Gather real-time production information and control with precision.
Measuring the Pulse Frequency
One useful application of the high speed input capability is to measure the speed of rotation of a motor. A simple optical sensor, coupled with a rotating disk with slots tted to the shaft of a motor can be fabricated economically. When the motor turns, the sensor will generate a series of pulses. The frequency of this pulse train relates directly to the rotational speed of the motor and can be used to provide precise speed control.
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Pulse input in a spesi ed period by a single instruction are counted, and the frequency is calculated
Setting range: 1 ms to 99,000 ms
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