Announcement

Collapse
No announcement yet.

Need help determining Ohm value of resistor.

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • #31
    By the look of the controller, its a basically just a variable resistor that will go in series with one of the fan wires. Now bear in mind that not all ac motors are able to be controlled by this type of controller.

    Also remember that you are dealing with mains voltage. If you are not sure of something, dont do it.
    If I was doing the job, once connected I would be testing insulation resistance of controller to make sure there is no leakage to the exposed metal plate and double checking all connections with professional test gear. Unfortunately there are too many electrocutions and fires caused from people performing mains voltage repairs/modifications/installations that they are not really qualified to do.

    Comment


    • #32
      Using a 5 Amp Max 120VAC, 60Hz analog Fan Speed Control with a 120VAC, 0,14 Amp 60Hz Fan

      CAS,

      Your last paragraph makes me a bit nervous about completing this project without burning anything up , but I do like your comment that "its basically just a variable resistor that will go in series with one of the fan wires."
      I should have noticed early-on that the Speed Control must be wired in series, since the wires are both black ! I've installed enough toggle switches on the wall to know that they are connected in series on the black side of the power supply cable........shame on me and my apologies.

      Regarding your comment "If I was doing the job, once connected I would be testing insulation resistance of controller to make sure there is no leakage to the exposed metal plate and double checking all connections with professional test gear", I've included two attachments with this post, one is a side view of the Fan Speed Control and the other shows the front of my meter. Now, if you magnify the Speed Control photo, it's easy to see there are pieces of white plastic tape between the black control housing and the exposed metal plate, nevertheless, I will test for insulation resistance using my meter set in the Ohms bell tone position. The photo of my meter is just so you can see the dial settings. That's the extent of my "professional" test gear, so "double checking all connections with professional test gear" really isn't an option for me I don't think.

      Lets say I decide to risk it and connect the Fan Speed Control in series with one of the Fan motor wires. I assume both of these white wires are connected to the motor coil, so it doesn't matter which white wire I use for the splice....right ?

      Having completed the splice, since you said earlier that "Your fan will only draw what it needs. The controller doesn't 'pump' extra current into the fan. The controller should be ok.", then I assume I can crank-up the analog Speed Control to it's max position without overloading the motor.......correct ?

      Thanks again for your help on this project !

      ToddB66
      Attached Files

      Comment


      • #33
        Originally posted by ToddB66 View Post
        CAS,

        Your last paragraph makes me a bit nervous about completing this project without burning anything up , but I do like your comment that "its basically just a variable resistor that will go in series with one of the fan wires."
        I should have noticed early-on that the Speed Control must be wired in series, since the wires are both black ! I've installed enough toggle switches on the wall to know that they are connected in series on the black side of the power supply cable........shame on me and my apologies.

        Regarding your comment "If I was doing the job, once connected I would be testing insulation resistance of controller to make sure there is no leakage to the exposed metal plate and double checking all connections with professional test gear", I've included two attachments with this post, one is a side view of the Fan Speed Control and the other shows the front of my meter. Now, if you magnify the Speed Control photo, it's easy to see there are pieces of white plastic tape between the black control housing and the exposed metal plate, nevertheless, I will test for insulation resistance using my meter set in the Ohms bell tone position. The photo of my meter is just so you can see the dial settings. That's the extent of my "professional" test gear, so "double checking all connections with professional test gear" really isn't an option for me I don't think.

        Lets say I decide to risk it and connect the Fan Speed Control in series with one of the Fan motor wires. I assume both of these white wires are connected to the motor coil, so it doesn't matter which white wire I use for the splice....right ?

        Having completed the splice, since you said earlier that "Your fan will only draw what it needs. The controller doesn't 'pump' extra current into the fan. The controller should be ok.", then I assume I can crank-up the analog Speed Control to it's max position without overloading the motor.......correct ?

        Thanks again for your help on this project !

        ToddB66
        Note: when working with mains voltages NEVER assume wire colours are correct. I have seen all sorts of coloured power cables especially stuff made in Asia.

        Any of the two wires will be ok.

        when the controller is set to max, it is basically a short circuit so the fan will run as though it is connected straight to mains.

        Comment


        • #34
          CAS,

          Thanks for your reply (post #33).

          I'll be splicing-in the controller and will let you know how it works.

          ToddB66

          Comment


          • #35
            Fan Speed Control Affect on RPM's of 1-Phase AC Motor.

            Dear CAS,

            As you know, I have an AC single-phase electric-powered Induction motor 120 V, 60 Hz, 0,14 Amp, Class B, driving a small squirrel-cage fan with activated charcoal filter, also a Lutron model FS-5F, 120 V, 60 Hz, 5 Amp max fan speed control that I am planning to connect in series with the motor to vary the fan speed (Photos attached for reference.).

            Am I correct that, when the speed control is connected to the circuit , the AC power is turned ON and the speed control dial turned all the way up, the motor RPM's will only reach the normal maximum running speed of the motor without a speed control device connected ? In other words, the speed control device can only lower the RPM's of the motor as I turn the dial toward the Shut-OFF position, but cannot raise the speed any higher than the normal maximum speed designed into the motor ?

            I know that for you this is probably like "beating-a-dead-horse", but I wanted to be sure my understanding of the speed control's affect on the motor RPM's is correct.

            Thanks in advance for your reply !

            ToddB66
            Attached Files
            Last edited by ToddB66; 03-18-2015, 05:07 AM. Reason: Adding another attachment to post #35.

            Comment


            • #36
              Originally posted by ToddB66 View Post
              Dear CAS,

              Am I correct that, when the speed control is connected to the circuit , the AC power is turned ON and the speed control dial turned all the way up, the motor RPM's will only reach the normal maximum running speed of the motor without a speed control device connected ? In other words, the speed control device can only lower the RPM's of the motor as I turn the dial toward the Shut-OFF position, but cannot raise the speed any higher than the normal maximum speed designed into the motor ?

              ToddB66
              Yes. Usually when the controller is on max, it will allow full voltage/current to the motor. The motor will only draw the current it needs.

              Comment


              • #37
                CAS,

                Thanks again !

                ToddB66

                Comment


                • #38
                  Thread title: Need help determining Ohm value of resistor

                  Dear CAS,

                  Well, in one of my earlier posts I had decided to put the Hamilton Beach "True Air" wall fan back together and use "as is" without a speed control device, but after thinking about it and getting more answers from you I decided to go ahead with my original plan and splice the LUTRON Speed Control device into the fan circuit and I did that today. As I promised to report, the results were as follows:

                  Everything works, except the speed control dial operates in reverse. Starting with the dial turned all the way counter-clockwise to the OFF position , when I turn the Speed Control dial clockwise to the ON position the RPM's of the motor are at it's highest speed and then begin to slow down as I continue to turn the dial clockwise.

                  I would prefer that when the dial is first clicked ON in the clockwise direction, the speed of the motor would start out slow and begin to increase speed as I turn the dial clockwise. Isn't that the way a speed control device should operate ?

                  So I tried reversing the Speed control black wires with the ends of the white motor wire I had cut, just to see if this would change the way the speed control worked, but this didn't change anything.

                  There are plenty of photos of the Top and Bottom side of the PCB and these can be magnified to get a real close-up view of the rectifier-diode , resistor and LED mounted on the PCB, the motor and wiring inside of the fan, in case you want to review.

                  What could be causing this reverse operation ? Looking at the traces on the Bottom-side of the PCB and relating that to the components on the Top side, do you think the rectifier-diode was installed backwards on the board at the factory ? Another thought, could the components inside the Speed Control have been assembled incorrectly at the factory ?

                  If there is no easy/cheap fix, I would rather use the Speed Control "as is".

                  I look forward to receiving your thoughts and ideas.

                  Thanks,

                  Todd

                  P.S. Your "Grab Bag" hasn't arrived yet, but that's OK........it will be exciting when it does !

                  Comment


                  • #39
                    Thread Titled: Need help determining Ohm value of resistor.

                    Originally posted by ToddB66 View Post
                    Dear CAS,

                    Well, in one of my earlier posts I had decided to put the Hamilton Beach "True Air" wall fan back together and use "as is" without a speed control device, but after thinking about it and getting more answers from you I decided to go ahead with my original plan and splice the LUTRON Speed Control device into the fan circuit and I did that today. As I promised to report, the results were as follows:

                    Everything works, except the speed control dial operates in reverse. Starting with the dial turned all the way counter-clockwise to the OFF position , when I turn the Speed Control dial clockwise to the ON position the RPM's of the motor are at it's highest speed and then begin to slow down as I continue to turn the dial clockwise.

                    I would prefer that when the dial is first clicked ON in the clockwise direction, the speed of the motor would start out slow and begin to increase speed as I turn the dial clockwise. Isn't that the way a speed control device should operate ?

                    So I tried reversing the Speed control black wires with the ends of the white motor wire I had cut, just to see if this would change the way the speed control worked, but this didn't change anything.

                    There are plenty of photos of the Top and Bottom side of the PCB and these can be magnified to get a real close-up view of the rectifier-diode , resistor and LED mounted on the PCB, the motor and wiring inside of the fan, in case you want to review.

                    What could be causing this reverse operation ? Looking at the traces on the Bottom-side of the PCB and relating that to the components on the Top side, do you think the rectifier-diode was installed backwards on the board at the factory ? Another thought, could the components inside the Speed Control have been assembled incorrectly at the factory ?

                    If there is no easy/cheap fix, I would rather use the Speed Control "as is".

                    I look forward to receiving your thoughts and ideas.

                    Thanks,

                    Todd

                    P.S. Your "Grab Bag" hasn't arrived yet, but that's OK........it will be exciting when it does !

                    CAS,
                    Guess what ! The light bulb finally went ON in my head. I checked the operation on one of my ceiling paddle fans and that's the way these Fan Speed Controllers work, for example, High Speed at the ON setting, then progressively slower as the speed setting is changed.

                    So, I'm back in business !

                    Thanks again for all your help !

                    ToddB66

                    Comment


                    • #40
                      Thread Titled: Need help determining Ohm value of resistor.

                      Hi CAS !

                      First, I received your "Grab Bag" of electronic components today, April 14, 2015 !

                      With all the different colors, it reminded me of a bag of jewels !

                      I'll have some fun now and learn more while identifying these components for future use.


                      Second
                      , thanks to your help, I've completed my fume fan for soldering and a couple of pictures are attached below.

                      As you instructed, I connected the two black wires from the Speed Control in series with one of the white wires from the motor and the Fan works great ! Then I hot glued the Lutron Speed Control to the back of the 'True Air' fan and then hot glued a thick block of Masonite to the underside of the Speed Control to serve as a steady-rest foot.

                      I can't thank you enough for all of your kind help.

                      Your friend,

                      ToddB66
                      Attached Files

                      Comment


                      • #41
                        Glad to see you got your fan all up and working. Now you just have to work out what the next project is!

                        Comment

                        Working...
                        X