Electrical Wiring in the Home/3 phase 20 amp plug

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Question
I have a plug (4 prong) on a cord for a meat mixer that is labeled x,y,z, and gnd.  The only replacement plug I can find at my local hardware store is the same pin layout, but the terminals are labeled w,x,y gnd.  The package is labeled nema L14-20P.  Do I have the correct plug?
Thank You
Tony

Answer
Tony I am sorry   you did say three phase,  so it all still applies,   the only difference is you will need to put the three phase on the power prongs and by keeping the wires in the exact order around the plug,  you should have it phased,  but I would bump for rotation being three phase just to be sure,    other than that the single phase advice applies equally to the three phase,  and again no worries about the lettering, just keep your three power leads in order and make sure the device is rated at or below 20 amps.    I KNEW I SAW THREE PHASE IN THERE SOMEWHERE<   A BIT UNUSUAL FOR THIS SECTION< BUT Three phase is what I work with more than single,   so you should be fine,   



Tony, everyone wants their own conventions,  non US electrical motors are often labeled with U1 V1 W1  and for six leads for a THREE PHASE wye or delta external connection,  use U2, V2, W2   it is simply a convention of labeling,   that is trying to get some kind of international labeling.

On the single phase side of things, which I believe you have,  it is a plug for the newer mandated IEC code that requires US 220 volt SINGLE PHASE TO HAVE FOUR LEADS  [the addition of a dedicated chassis ground versus the forever use of three leads for 220 volt single phase,  using the neutral as a dividing point as well as the ground.

Studies have shown that during a severe short,  the fault current is so high a dedicated ground helps in tripping the breaker and handling the huge current from a fault.

THE NEW plug YOU ARE LOOKING IT IS this:


PRODUCT OVERVIEW

This heavy-duty cord plug is for use with portable generators up to 5000 watts. NEMA L14-20 configured and UL listed, the L1420P features a 5-year limited warranty. Rated 20 amps at 125/250 volts.

   Rugged and durable
   NEMA L14-20P configuration
   5 year limited warranty
   UL Listed
   MFG Model # : L1420P
   MFG Part # : L1420P

Info & Guides

  

SPECIFICATIONS
Assembled Depth (in.)     2 in     Assembled Height (in.)     3.75 in
Assembled Width (in.)     2 in     Certifications and Listings     1-UL Listed
Color     Black     Color Family     Black
Color Family     Black     Color/Finish     Black
Commercial / Residential     Commercial / Residential     Electrical Product Type     Plug/Connector
Hospital Grade     No     Manufacturer Warranty     5 years
Material     Thermoplastic     Material     Thermoplastic
Maximum Amperage (amps)     20 A     Plug/Connector     Plug
Product Depth (in.)     2     Product Height (in.)     3.75
Product Weight (lb.)     0.3     Product Width (in.)     2
Returnable     90-Day     Voltage (volts)     120/240



Forget the confusing letters and numbers on the actual connections.  You apparently have a single or have your dual voltage machine wired for the voltage you need,  which is a very basic three lead [with chassis ground] hook up.

I am assuming it is single phase 220 volts,  so you will need to match the POSITIONS OF THE TWO HOTS AND THE NEUTRAL, from existing plug to new plug.

Your concerns are one     form fit and function,   meaning will it mate with the male or female plug,   be it twist, straight in, whatever the case.

This appears to be twist.

As long as your machine is rated at 125 to 250 volts,   [actually the slash means one or the other, but logic would tell you that anything rated to 250 volts is adequate]

As long as someone has not put a single phase plug on a three phase machine,  it should be fine,   so I have to assume you are dealing with either 120 or 240 volts, single phase, if anything else let me know.

Next is the machine rated for 20 amps or less regardless of the voltage?

This is really the big one past the actual fit,  it must handle the CURRENT/AMPS of the device.

Never NEVER assume the existing plug is the correct plug. You never know what someone before you has done, or even at manufacturing,     so check the machine rating,  and make sure it does not call for more than 20 running amps.

Past that it is simply a matter of matching the hots and neutral, connecting your chassis ground, and forget the Xs and ys  while their are single phase identifications it won't matter if you marked out the letters, as long as your two hots and neutral go back in the same positions    if you swap the two hots, not a problem.

The only problem in the match up is getting one of the hots in the neutral slot and the neutral in one of the hot slots.

Generally speaking, if the prongs fit, the amperage rating is the same, however   AGAIN<  make sure the existing plug is rated correctly for the device.

What happened to the existing plug?  This is why I am pounding on the amperage ratings.

If somehow someway  a lower rated plug  [in either voltage or mainly current/amperage] was installed on and a matching receptacle, the plug might look melted or distorted.

Do not repeat someones mistake,  check yourself.

Once you verify the plug is able to handle the device amperage, and the prongs fit,  and are matched hot to hots,  neutral to neutral,  and connecting your frame/chassis ground,  you should be in fine shape.

They tend to confuse the hell out of everyone with new and different lettering,  like everyone is studying the NEC for a hobby.


If you are the least bit confused after this reply,  get back to me, and I will see you through this.  And there are no stupid questions so ask away.

Again  check the amperage rating on the device, if lower than the 20 rating on the plug and all prongs physically fit,  and you keep your hots in the same slots, to the receptacle all should be fine.

And if for some reason, the existing plug failed in some sort of melted or destructive looking manner,  we might want to talk before proceeding.

It happens all the time,  a circuit is installed, along comes the user,  need the 220 volts or the higher amperage 120,   and instead of checking that what they are plugging in fits the tolerances,  they just match it physically,  next thing you know the device is rated for 30 running amps on a 20 amp P & R.

So if anything is a concern,  get back to me and let's go over it before you spend the money on the plug which might have been wrong from day one. Also pay no attention to the wording that the plug is designed for generators,  we just want to match the device, whatever it is in both voltage and amps. If you look on the device plate and see amperage at something higher than 20,  then we need to talk about the entire feed,  wire size and all,    if lower or at 20 all is good.

Will BABBITT  
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Electrical issues of all types, wiring, control, appliances, components, specialty in Electric MOTOR or APPARATUS trouble shooting, electric motors, electrical problems, single phase, three phase, DC, capacitors, elevator MG-Sets, modifications, reverse engineering, VFD Drives, single to three phase convertors. Repair of most any electrical/mechanical/electronic apparatus, OEM, AC, DC, Industrial Applications, Three phase, single phase failure mode, determining the root cause of the equipment failure BEFORE failure repeats, Antique appliances, electric motors, fans, ceiling fans, base mount fans, poor equipment performance, Modifications, habitual failures, vibration, redesign, obsolete issues, collectible items restored, rewinding. Owner of EMR Repair Inc www.emrrepair.com More information on electric motors, under Engineering/Motors Ask about any electrical or mechanical problems in the home, office, or even at your work. B2B or business to business CONSULTING I can do but it would be a much more complex issue, that would require a significant amount of time. repair@mearservice.com from there we can discuss and begin work on about anything. Industrial electric motors, controls, troubleshooting, vibration, alignment, any type of industrial or commercial electric/electrcical equipment For the home owner, renter, apartment if you have odd things going on, describe to me, photos are normally very helpful, appliances, heating and air conditioning issues, light switches, installation, DIY PROJECTS FOR THOSE NOT EDUCATED IN ELECTRICAL, we can do some things, but for safety and sanity reasons, I may refer you to a local electrician, and help you find one, help you with pricing and even speak directly with anyone you hire if you have issues,

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