I want to change the rotation direction of a motor. I want to do this by using two limit switches as inputs. One output goes to the frequency inverter to drive the motor clockwise, and another output goes to the inverter to drive it counterclockwise.

I also want to add a start button, where the motor starts rotating in the same direction it was rotating before it stopped. The start button is a toggle switch that stays high. The motor should be able to start when both limit switch inputs are low.

I have attached a picture showing what I’ve made so far, and I’m wondering how I can add the start button.

Hi

Your explanation is a little bit strange, because as far as I know, the inverter can change the direction of rotation by switching just a single input, e.g. 0 = clockwise and 1 = counter clockwise.

Why do you need to use 2 outputs to do this?

@Padre Pio.. It very much depends on the drive you have an how that drive is configured. I prefer using a “Run + Forward” and “Run + Reverse” control inputs on Japanese / Chinese branded drives. Some of these go into a stop condition if both those inputs are triggered.

@AutoGen_7893350.. Are you using N/O or N/C limit switches? Consider building a circuit that uses a SR latch.

Try it this way. Please observe the safety instructions.

Regards, Quirin

Can you send it again as an v8.1 version?

 I can't open it now.

I'm using N/O limit switches.

@AutoGen_7893350.. Are you using N/O or N/C limit switches? Consider building a circuit that uses a SR latch.

Here is the version for LSC 8 Standard.

I have provided NC limit switches. If using NO limit switches, simply remove the negation at the R/S inputs of the RS blocks.

Regards, Quirin

Hi

Your explanation is a little bit strange, because as far as I know, the inverter can change the direction of rotation by switching just a single input, e.g. 0 = clockwise and 1 = counter clockwise.

Why do you need to use 2 outputs to do this?

I'm using a Danfoss VLT drive. As far as I know, you've two inputs. One is for clockwise and the other for counter clockwise.
But if I can make it with only one output, I would prefer that because I've only 4 outputs on my logo (as we all have of course).

Here is the version for LSC 8 Standard.

I have provided NC limit switches. If using NO limit switches, simply remove the negation at the R/S inputs of the RS blocks.

Regards, Quirin

Thanks a lot!

AutoGen_7893350

Hi

Your explanation is a little bit strange, because as far as I know, the inverter can change the direction of rotation by switching just a single input, e.g. 0 = clockwise and 1 = counter clockwise.

Why do you need to use 2 outputs to do this?

I'm using a Danfoss VLT drive. As far as I know, you've two inputs. One is for clockwise and the other for counter clockwise.
But if I can make it with only one output, I would prefer that because I've only 4 outputs on my logo (as we all have of course).

 

Here is the version for LSC 8 Standard.

I have provided NC limit switches. If using NO limit switches, simply remove the negation at the R/S inputs of the RS blocks.

Regards, Quirin

Thanks a lot!

It should be possible to change the Danfos drive to handle Run + Direction. It will also be possible to use only one LOGO! output. But that means you have to use another strategy to give the Run command to the drive. That means building an electrical circuit.

A simple option would be to use a selector switch connected to the Run input of the drive.

A better option would be to build a self retaining relay circuit. It would use a normally open Start button, normally closed Stop button and a relay. The advantage is that a power outage will also interrupt the Run signal.

So how experienced are you in finding the parameter setting on the Danfos VLT drive?