# Encoder to PLC connection and Touch Screen

A

I have a 200 pulse encoder made by LINE SEIKI Co.-Japan (Model:CB-200HC). I need to connect it to PLC: LG - MASTER K10S1 with HSC inlet connection (VDC) and to program it to cut a fixed length of a steel piece, where a certain length is programmed and a hydraulic press will hold the piece until the saw blade cuts it then a new piece should go forward for next cutting. So the PLC ladder diagram should activate the incoming conveyor with piece on top of it then at a given length given by a preset value it will stop when the encoder value reaches the preset one and the other procedures will follow as they are with no changes at all. I need to connect the PLC to a touch screen so that the preset value will be changed from the screen.
Can you help me in showing me the right connections to be installed between the Encoder/PLC/Touch Screen with the proper ladder diagram for this simple arrangement?

Thank you.

K

#### Ken E

What type of motor is on the conveyor?

This application worries me because if you are just turning on a motor and waiting for an encoder to count up your ability to control overall length of your piece is bound to the repeatability of your motor deceleration time. If all you need is very crude positioning at very low speeds, I guess this is fine.

I'm sure there are people on this forum willing to do this project for a fee, but you are basically asking us to show you how to solve this problem for you. I don't mean to speak for control.com but it would seem that this forum is more meant to provide general peer to peer advice and not "How do I do my whole project?".

KEJR

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#### Rishabh

I have to connect encoder of 1024 pulses in Schneider Electric M series M218. I want to have RPM calculation... Please guide me Regarding this...

Gear Ratio:150:1
Roll Dia: 120
Encoder Pulses : 1024...

K

#### Ken E

This is basic high school math, Just think it through.

e.g.

1024 counts/1Rev

Then either multiply or divide by your gear ratio depending on where it is located.

Roll diameter shouldn't matter unless the encoder is on a wheel following the roll in which case you need to know the ratio from encoder wheel to the actual wheel its following, etc.

Just do the basic math and then rotate the system some known amount of rotations (by hand or by jogging) and your result should be pretty close if you have it right. Its also good to run it for a while and see that your encoder is not losing counts or something like that due to some non-linearity, etc.

One you have the number of counts/rev you need to introduce some unit of time. The most accurate way to do this is to capture with position with a periodic hardware timer interrupt, or something like that. Depending on your desired accuracy you could just use a PLC timer.

RPM is simply:

RPM = (Number of Revs since last calculation) / (Amount of time since last calculation in minutes)

Good luck.

KEJR

You didn't mention the mechanical system. For instance, why does roll diameter matter in this calculation? Is the encoder following this on a subsequent wheel? If not I don't think it matters.

Etc...

B

#### bob peterson

Is this a quadrature encoder? some times the counters will count 2X or even 4X what the base rate is (1024 in this case).

I am guessing since you told us the gear ratio of the gear box that the encoder is on the motor that feeds the gear box that actually turns the roll. presuming the gear box gears down (a reasonable presumption), one revolution of the motor (1024, 2048, or maybe 4096 counter pulses) would be 1/150th of a revolution of the roll.

Unless there is some other issue involved, the roll diameter does not figure into the equation at all.

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Bob