2 different speeds with powerflex 525 on one switch.

I am trying to have a 3 position switch where to the left is 27hz the middle is off and to the right is 37hz. I set digital input 5 and 6 to to spd + strt 2 and 3 and set up the paramaters for P048-P051. but it isn't working like i thought it would. Do i still need the run command from digital input 2?

Ive tried several things and i think i am just way overthinking it at this point and missing something super simple...

I dont know the powerflex drive at all, but most work the same. Normally with preset speeds, in your case 2 preset speeds both digital inputs will have to be on to activate the 2nd preset speed. You will have to use relays according to me. So 1st relay will switch on with switch on the left, this relay will go to assigned digital input for preset speed 1 and also give a start signal (The drive will also have to be setup for 2 wire control and not 3 wire, unless you have a seperate start and stop button)
If the switch is on the right it will have to switch on both relays with the second relay giving a signal to another digital input assigned to preset speed 2.
Again i dont know the powerflex but most drives should work this way

yes, you will still need the run command.

the DI for the speeds just tell the drive what speed to run, the run command tells the drive to run.

I guess i thought since digital input 5 and 6 were set to Speed and start that it would be a run command along with the speed. But i guess i was wrong.

What i ended up doing that works is set 5 and 6 to just preset freq and then jumped the 24v to the run command. so to the left it is 25. to the right is 35 and in the middle is 0. I just don't know if having the run command all the time is OK to do.

Moliner said:

I guess i thought since digital input 5 and 6 were set to Speed and start that it would be a run command along with the speed. But i guess i was wrong.

What i ended up doing that works is set 5 and 6 to just preset freq and then jumped the 24v to the run command. so to the left it is 25. to the right is 35 and in the middle is 0. I just don't know if having the run command all the time is OK to do.

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In general, it is not a good idea to have a run command and a zero speed reference, since the VFD could be attempting to hold zero speed and still send current to the motor. This could be unsafe for personnel and/or damaging to equipment.

In practice, it is often possible to set up the VFD to stop when the speed reference is below a specific value. I have done that with analog speed control, never tried to look into this for a preset speed setup.

This might be worth checking into to help you avoid having to run more wires and add contacts to your selector switch.

So I looked more into it and you can use the Relays on the drive itself to use for the run command when a condition is met on the digital inputs. Thank you everyone for your help and giving me ideas. I hadn't done this before on just a drive without a PLC involved.