Lesson 3  Source of Operation in VFD- Variable Frequency Drive

Lesson 3 Source of Operation in VFD- Variable Frequency Drive


Alright so next parameter is source of operation command ok now this operation means on/off. On/off control your direction control and the jog control multi-step speed control that’s the source of operation. Ok! So the first says operation determined by a digital keypad so now this means we can Start /Stop the drive using the switch ‘Run’ and that is going to start the drive and this stop is going to stop the drive. This is source of operation my digital keypad by default because here if you see it says parameter – 01 operation determined by a digital keypad this is by default okay Then we have second one is – Operation determined by external control terminals keypad stop is effective. Ok ! Now external control terminals are these terminals, the first one was digital keypad and that was the run and stop. Second one was external terminals these are terminals from M0 to M5 keypad Stop is effective. It means Start/Stop operation can be done through these terminals but along with that Keypad stop will also work okay now these terminals let me see the diagram these are your M0 to M5 so external terminal says when you provide ground to these terminals then motor can be controlled so what can be the exact figure let’s see the first mode 2- Wire control -on/off and direction from toggle button so it says this is your ground okay when ground is connected to M0 this is source of external control okay in this we have different modes this is the first mode- when ground connects to M0 motor will run into forward it says when M0 is open- when ground is non connected! Motor is stop When M0 is closed motor will run in forward direction okay this is achieved by putting you know ‘0’ in parameter 38 now this 38 is associated with this parameter source of external because you have different modes so we have two enter two parameters. First is we have to enter 01 in P01 so here we have mode that is parameter 00 – Enter 01 here we have to enter 01 okay now source of control is external from these terminals ok it has been changed now in parameter 38 we have to enter 01 so let’s see parameter 38 over here which says yeah this one multi-function input terminal M0 – Forward/Stop; M1 – Reverse/Stop ok so this figure says when M0 is close – forward (RUN) when M1 is slows reverse (RUN) alright so for that let’s go to P38 and enter 01 so parameter increment to P38 This is P38 – go to enter – enter 01 That’s it! now go back to frequency so right now frequency mode has been previously set to potentiometer. Now how to run the drive? How to put ground to M0 for that I’m using a PLC because this is already wired to the PLC you can also use switches, push button,s toggle switch but just to explain what I’m going to do is if I turn on Y0 this ground will travel from common to Out0 to M0 so motor will run forward because we have selected to mode. If I turn on Y1 then motor will RUN reverse. Okay! So that’s the ladder I’m going to make ladder here so let’s take LD (a dummy bit) LD M30 —- OUT Y0 we zoom out of it yeah and then in the second ladder LD M31 OUT Y1! okay so now loading this program to the PLC. now when you see this motor over here when I turn on M30 motor will run in forward direction and start running and I can change the speed from here so that you can see the direction I’m decreasing the speed this is rotating in forward direction if I turn this off motor will stop this will turn the motor in reverse direction okay prevents is bit low so that’s it’s not started! Hold on! we have put 01 !! oops we have put 01 here it says M0 is run/stop M1 is reverse/forward. You have to enter 00. By mistake i entered 01 it should be 00 ’01’ is something else which I’m going to cover in next session. Okay so it should be 00 the first mode now when I turn on M31 motor will run Reverse okay and to see the direction this is the led but to see the you know the exact reverse mode you can find here this is reverse okay and motor is running if I turn off – Motor is stop when I go to M30 again now motor is running in forward okay this is stopped with this one it’s reverse again so that’s actually happening because we have entered the parameter in such a way that M0 will take the motor forward M1 will run the motor reverse. This is the ground signal okay that was the first mode M0 forward/stop & M1 reverse/stop alright so this was the ‘Mode 1’ let’s see the ‘Second mode’ so this was 0 ! okay Second mode says when you put ‘1’ in parameter 38 M0 become run/stop command and M1 become direction command. Now earlier we have in M0 we have forward plus run ok here it’s only run in M0 earlier in M1 we have reverse plus run here in M1 we have forward and reverse – toggle of the direction if M1 is closed direction will be reversed provided this M0 should be on then it will run reverse if M0 is off , if M0 is open and if you keep on changing M1 it will just give the direction command it will not run the motor which was happening in earlier mode. Here the Run and reverse direction command is going together. Here the run command is by M0 and direction command is by M1 so let’s just put 01 in parameter 38 to see what will happen so P38- I’m going to enter 01 …alright! this is frequency 5.8 now let’s see the change in the operation now when I run M30 this is running okay and the direction by default is forward this is forward if I run M31 along now it will run reverse it will stop and run reverse then if I turn off this one it will still run but in forward because this is the command so if I turn off this motor will be stopped and if I turn on M31 it will just change the direction command this is now reversed selected to reverse! If I turn it off selected to forward but that’s the direction command which was not happening earlier this is this RUN and Stop command! So it matters it’s based on your application how you want to control the motor whether you have a push button or the toggle button or you have a sensor that decides which mode you want to use okay let’s move to last mode which is three wire control. Most widely used in your panel control which says this is your ground and you have to first connect a NC switch this is a symbol of NC switch external NC switch with that you are giving a signal to M2 and another NO switch to M0 and M1 is for direction so that now M1 has a toggle switch which can select the direction if it is closed – Reverse direction if it is open it is a Forward direction but this push buttons are used to – latch the motor okay now here motor will be latched internally you just have to press it once. The motor will be latched of its own okay this was about three wire mode. So let’s try that using a PLC although it doesn’t sound good to work on this mode using a PLC but just for your demonstration okay so first of all let’s put in 02 in P38 it’s Parameter 38 okay now if you carefully see this diagram M2 is having ground signal continuously okay. M2 should be continuously ON. M0 should be given a pulse input okay so M0 is my Y0. This should be given a pulse input should be turn on and then turn off, then motor will be latched provided this M2 should be ON. Sso M2 is Y2. So Y2 should be always ON. So let me take Y2 as well. LDM32 — Out Y2 Now It’s recommended when you change the mode of your drive you should restart your drive. So let me reset my drive by flipping the MCB then turning it on again. And this logic over here – this is Y0 M0, M1 and M2. This will decide the direction this is the OFF and this is the ON. Turn on the drive again now when at this I have to download my PLC program as well. it’s downloading now this should remain on this is your off state okay when you just turn on this one and turn it off see the motor is latched a motor keeps running because I just have to provid a pulse to Y0. This will change the direction okay Forward and Reverse! how the motor will be off when you turn OFF this one for a moment. Set off and if you again turn it on motor will remain stopped. So how it will start again when you just provide a pulse to Y0 which is your M0 like that ON and OFF. Motor is latched … motor is unlatched. Okay! This is about 3 wire control and your VFD, this is one of the control modes so we have done we have done operation determined by external control terminals keypad stop is effective it means motor can be stopped by keypad as well so if i show you here if i turn ON this one motor is ON. Now when i want to turn off the motor i can press this one see motor is off keep it stop as effective so in case i don’t want this keypad stop to be effective i can go back to my parameters and I can put 02 which says operation determined by external controlled terminal keypad stop as ineffective okay so parameter 01 put 02 now go back to main mode and let’s start the drive now when I press stop here it will not work it’s not working so it’s up to you whether you want to have this feature or not. So that …in you know that you can avoid people you know playing with your drive by just pressing the button unknowingly so you can avoid these buttons you can avoid stop from this drive. That’s up to you totally up to the programmer and then how you want to make the application. Okay so this was keypad stop effective …this was ineffective we have done this 2 wire control .. this we have done… 3 wire we have done now moving on to this one yes source operation by rs-485 communication port now this communication port as I told you I have already done that you can find the Modbus communication video in the description of this video we have already made a video in that case how we can control the stop and start and jog using a Modbus combination this is very important very effective and in this case also we have Keypad stop effective one of the option and keypad stop ineffective the second option. Ok so in this video we have seen different modes first was the digital keypad, then operation by external control terminals – in which we have done 3 modes: 2 Wire Control Mode A, 2 Wire Control Mode B and 3 Wire Control and we have seen this effective and ineffective feature as well. Rs 485 we have already covered. So this was about source of operation command you can control by various elements one a station keypad then from the external terminals effective ineffective three modes and 485 If you have any queries post a comment I’ll get back to you thank you

23 thoughts on “Lesson 3 Source of Operation in VFD- Variable Frequency Drive”

  1. dear sir in this video not control by RS 485 i want operation determine by rs 485 communication port as u send me link i do all this parameter but cant communicate plc and drive so plz send me description 

  2. hello sir,
    I am STILL unable to increase speed of conv. MORE THAN 100HZ after setting P032=100HZ & P035=100 HZ FOR AB POWERFLEX 40
    CAN U PL. GUIDE ME

  3. hi singh sab main ny es sy pahly be sir ap sy request ki thi ky sir English main to bahut sy log es achy kam main lagy hyn ky logon ko kuch sekha rahy hyn ager ho saky to sir Hindi main logon ko sekhany ka kam ap shuroo karyn bahut sy log aysay hyn jo ap sy sekhna chaty hyn
    ager ho saky to sir zaroor es par sochye ga 

  4. Hi Rajvir, good VFD demo!

    I watched the series as I am trying to use a 4:20Ma pressure sensor to vary the frequency of a 1HP 3 phase motor that drives a small gear pump, that pumps oil. I seek to have the sensor vary the current to maintain a constant oil pressure. Anyway the current does vary as the pressure changes but I'm getting no change in frequency, therefore RPMs of the motor.

    I liked the PLC you used and the software can you advise what it is? The ladder stuff seemed quite intuitive. I have a commercial heating business and am looking for a good 'all-rounder' PLC

    Cheers, Greg [[email protected]]

  5. does the C2000 remain in the same parameters? i wire the potentiometers correctly but i cannot get the push buttons to function correctly in forward and revers.. 🙁 please help

  6. Hi Rajvir,

    Thanks for the awesome demonstration. I would be great if you can help me out with a problem.

    I am using the same Delta VFD-M for my project. My requirement is to read 16 registers starting from 2000H and control using 3 wire mode, I am using Arduino nano as the base master micro-controller for my purpose along with the MAX485 breakout board.

    Unfortunately I couldn't read anything. I tried multiple codes & libraries for solving this, please help me out with some code.

  7. sir this very good and easy way to control motor speed.you can set frequency in another mode though avi and terminal control in another mode.my question is that if i want to control both of them though hmi then the mode of both control is available if yes then what mode please help me

  8. Sir please tell me the pr no in delta m series, I move a flywheel to a motor, when flywheel run on 700 rpm, I switch on from motor to vfd, in this situation my flywheel rpm 0 then starts motor, I want to increase rpm after vfd connected motor, tell me the solution

  9. Here you have connected ground to external control terminals, that means is the vfd switched to sink mode,so you are connecting ground to external control terminals.If the vfd is switched to source mode, is it true that we have to supply 24v to external control terminals. Please clarify.

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