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-   -   Wiring a two wire 240volt breaker into a three speed motor (https://www.askmehelpdesk.com/showthread.php?t=835060)

  • Oct 19, 2017, 09:54 PM
    minibike6969
    Wiring a two wire 240volt breaker into a three speed motor
    I'm trying 2 hardwire my attic fam motor into a already installed 240 breaker.my fan motor is a 3peed 208/230 volt motor and the breaker is a 2 hot wire breaker how would I wire the 2 hot wires into the motor and would I need to run a wire from the netural bus bar and the ground bus bar of the fuse box to the motor?
  • Oct 20, 2017, 12:51 AM
    ma0641
    Is this the same motor you previously asked about? 2 hots and a ground for 240.
  • Oct 20, 2017, 02:07 AM
    minibike6969
    Yes I just need to know how to connect the two hot wires and do I need to add a ground and a netural wire
  • Oct 20, 2017, 05:03 AM
    donf
    If you want exact instructions, you need to give us the model number of the motor. You will find that on the motor's nameplate. If I have the model number I can get the wiring specs from the Dayton or Grainger websites.

    Okay, your replacement motor should have come with installation instructions. Those instructions will show you how to connect the two Line wires and the Neutral and Ground wires to the motor for the 240V connection.

    What is the amperage of the installed circuit breakers? This is critical to the sizing of the cable from the breaker to the fan's junction box.

    The wires going to the fan motor from the panelboard, are they a cable or individual wires in conduit? If they are in conduit, then you can pull a Neutral (White) from the panelboard to the junction box.
    However, the wires are in a cable sheath, then you will have to pull a new cable from the panelboard to the junction box for the fan connections. You will need a cable sized for the fan motor's "FLC" and multiplied by 1.25.

    It looks like a "copper" 14/3 with ground would be sufficient, however, I would choose a 12/3 w ground if it was me doing the work. ********Also, if I looked at the correct motor in the Grainger catalog I would not use a circuit breaker larger than 10 amps.
  • Oct 20, 2017, 10:23 AM
    minibike6969
    Mfr mode#l4m101 at grangers the installed breaker is 40amp the motor wires individual
  • Oct 21, 2017, 03:49 PM
    donf
    Okay, we were looking at the same motor at least.

    This motor does not require a Neutral. One conductor will go to the purple conductor and the other goes to the switch.

    A 40 amp circuit is way to high for this motor, given the horsepower of the motor I would not go over 15 Amp.
  • Oct 21, 2017, 08:35 PM
    ma0641
    There is no neutral on a 240 VAC setup for a motor, hot, hot, ground. A dryer 120/240 split uses a 4 wire hot, hot, neutral, ground. The wiring diagram for the motor should show hots to the switch and ground straight through. Wires from the switch go to the motor lugs. A 3 speed motor would have windings with taps. Ground goes to the motor frame. Is there a capacitor in this motor? This must be a very large attic fan motor. I have never seen a 240 in a residence, 2 speed 120VAC is most common. Do you have a 3 way switch too? Rotary lo-med-hi? No diagram on it?
  • Oct 22, 2017, 06:26 AM
    donf
    1 Attachment(s)
    1. https://www.askmehelpdesk.com/attach...&stc=1&thumb=1Here is the wiring doc from the Grainger website.
  • Oct 22, 2017, 08:30 AM
    minibike6969
    My fuse box is full so can't add another fuse,so what I am doing is adding the attic fan to this 40amp breaker already installed with a load that pulls 27/27amps and the attic fan motor pulls 3.9-4.3amps. So would the breaker be able to handle both loads? there is no purple wire on this motor only(red,blk,blu,wht,brn,brn w/wht,yellow,and orange)
  • Oct 22, 2017, 10:17 AM
    ma0641
    "Fuse box" or is this your usage term for a breaker box?
    1. My fuse box is full

    Sorry, your comment regarding attaching the new fan, with a 14 or 12AWG wire to a 40 Amp breaker, defies logic. No, you won't overload that circuit but your fan circuit will be totally unprotected since the fan can fail and the 40 Amp breaker will not trip. Great way to burn your house down. Please, get a local electrician to do the work.
  • Oct 22, 2017, 10:51 AM
    donf
    You need to stop here and get real honest with us. You indicated that you were replacing your existing fan motor, not extending an existing circuit.

    The 240V circuit you want to extend to this fan, what is it used for? There are some circuits that by definition are dedicated and there are some circuits that the appliance manufacturer will require a dedicated circuit for. If you are intending on extending a circuit from a dedicated circuit, that is a serious code violation. Also, it is very risky putting a 40 amp circuit to a motor that at worst case would only need 15 amps.

    I looked at this motor on the Grainger website and I do see a "Purple" conductor on the motor. I do not see an Orange conductor.

    The Brown & (Brown/White) conductors are for the capacitor. The Black (high) - Blue (Med) - Red (Low) are for the output of the switch.

    Rotation of the motor is controlled by switching the Yellow and Purple connection caps.

    Orange is not shown or pictured. It would be speculation at best but it appears to me that Purple has been swapped out for Orange. You really need to contact Dayton and / or Grainger to make sure.

    There are notes on the website directing you to review the installation instructions that are packaged with the motor. Do you have those instructions?

    FYI - the conductors for a 40 Amp circuit require a #8 AWG conductors. The motor's leads are to small for that amperage and will either melt or burn if an over amp occurs. Not to mention the switch, what amperage is it listed for?

    You might want to consider installing a secondary panelboard for these two circuits and feed that panelboard from that main panel. This would allow you to set up the two circuits from the secondary panelboard and protect each circuit with the proper breakers for the required conductors.
  • Oct 22, 2017, 11:48 AM
    minibike6969
    Nobody said anything about the wire size so please do not reply to any of my ouestions thanks
  • Oct 22, 2017, 11:50 AM
    donf
    I'm sorry that you do not like the answer, however, would you rather have a fire because you placed 40 amps across a wire that is only listed for 15 amps?

    Because that is what will happen if you just tap onto a 40 amp circuit.
  • Oct 22, 2017, 11:57 AM
    minibike6969
    Understand nothing has been done am just asking question as I said before the manual says a purple wire but the motor does not have a purple wire only orange so I'm thinking the orange wire works the same as the purple wire would

    My reply was not to you donf
  • Oct 22, 2017, 12:17 PM
    donf
    I agree that the purple wire may have been changed to Orange, however, that answer must come from Dayton.

    It may be as simple as running out of purple wire during a production run and Orange was substituted. I've seen that happen lots of times. However, Dayton should have either amended the instructions or put in an errata identifying the change.

    With respect to the wiring comment by MA061, he is absolutely correct. A #8 AWG copper and insulation wire is listed for 50 Amps. That's an incredible amount of heat from the current passing through it. On the other side of the spectrum is a "14 or #12 AWG wire. Neither of those wires can handle anywhere near that amount of heat and will melt and possibly burn. If those same conductors touch, the resulting spark can and will cause a fire.

    Setting a secondary panelboard and using it to fed two 240 volt circuits is the safest way to go.
  • Oct 22, 2017, 05:54 PM
    ma0641
    My point is this-SAFETY for you, your family and your home. What you are attempting to do is improper from a code standpoint and can be dangerous. The breaker or fuse protects the lowest amperage in a circuit, not the highest. You also need to understand that wiring for a motor is different than a straight resistive load. How do you plan to switch speeds? Is your controller designed for 240VAC? We would be remiss to tell you "sure, hook it up this way". The safest way to install this motor is to use a subpanel and run a new wire or, use a 2 pole breaker if it will fit. Don't be tempted to put 2 wires on 1 breaker, that is not code unless the breaker is specifically rated for same.
  • Oct 26, 2017, 07:39 AM
    minibike6969
    1 Attachment(s)
    I'm sorry had to call granger to the right diagram the motor I have is #4m101bgAttachment 48903 now how would I wire the two hot wires and what size wire
  • Oct 26, 2017, 01:17 PM
    donf
    Sorry, but there are no installation instructions in that document. The last page does show electrical connections but I believe these are internal to the moto.

    The motor you have should have a "Name Plate" on it, please either take a picture of the label or place the Model number from that label into this thread. I'll wait for your response.
  • Oct 26, 2017, 01:28 PM
    donf
    Question: Do you have a White conductor and A Black conductor going to the motor?

    It might be that Dayton just assumed a Black/White cable but you have a Black/Black.

    If that is true, then one of your Black wires will go to the White lead. The other Black would go to the black that feeds the switch.

    As to the wire size, the smallest household conductor you can use for this circuit is #14 AWG. This would allow up to 15 amp. As discussed earlier, if you put the 40 amp from those two breakers across those two 14 AWG conductors you will most likely create a fire situation.
  • Oct 26, 2017, 02:38 PM
    donf
    OKAY!! Sorry for the length of this response, but please read it.

    Stand the motor on its back with the Armature will be sticking up. Look at the label, over on the right side under the barcode you will see the wiring diagram.

    The top two wires are the source connections. The first wire (White) is listed as common, connect this wire to one of the black conductors from the breakers. The other black conductor from the breaker goes to the black from the motor.

    This motor will only draw about 4 amps when running. On a 40 amp circuit, it will still only pull 4 amps. The danger becomes extreme if for any reason the moto locks up. If that happens the motor will keep trying to run until it literally burns up. That's why you do not want it on a 40 amp circuit.

    Fortunately, this motor has internal "Overprotection" which wiil trip out to protect the motor.

    Now, how you get from the outlet to the fan is another story. You just cannot connect a #14 AWG conductor to a 40 amp circuit you have seriously compromised the safety of your home. So you would have to wire #8 conductors from the outlet to the fan and then connect the fan conductors to the supply conductors.

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