Description
BENTLY 3500/92 136180-01 Signal Overlapping Relays
BENTLY 3500/92 136180-01 often encountered in the engineering design of the control system signal is too much and the PLC input points are not enough, and increase the hardware requires additional investment. How to use the existing equipment to handle as many data points is a problem worth exploring.
BENTLY 3500/92 136180-01 Methods of reducing the number of input points required
a. Group input
Since the automatic program and the manual program are not executed at the same time, the two signals can be considered to be superimposed and grouped into the PLC according to the requirements of different control states.
b. Combined contact input
Such as a two-place start, three-place stop relay-contactor control. In the PLC control circuit, the three stop button can be connected in series to an input point, the two start button connected in parallel to an input point, so that the number of input points occupied greatly reduced. And the realization of the function is exactly the same.
BENTLY 3500/92 136180-01 makes full use of the PLC’s internal functions. Use the transfer instruction to connect a switch on one input as a manual/automatic mode switch. Manual and automatic operations can be distinguished by using the transfer instruction. Starting and stopping of a single button can be realized by using a counting instruction or a displacement register, or by using an alternating output instruction.