Electrical Wiring in the Home/pump start relay

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Question
where does the neutral wire terminate from the incoming service(not the red,black,ground) but the white wire? any help would be appreciated,thank you.

Answer
Because there is really no TYPICAL connection involving motor starters  especially single phase,without knowing more about your system,  HP< voltage, type of relay, brand so on, it is impossible to answer this to the exact setup you have

Below are some examples that might help,  generic,  but one might match up,  some use three phase starters for single phase motors,  some use single phase relays  some have stop start manual and some auto,   so hard to say,  

In general from a home panel,  the 220 is white to red 110/120  volts,    white to black is 110/120 volts   white is neutral,   ground is earth ground period, it should have continuity all the way from the breaker box to and through all relays, switches, whatever,    so it stands alone,  must be the right size wire,  and keep each device frame with a ground connection,    

The purpose of a ground is not what most think,  a ground is a clean and hopefully the least resistive connection from load to breaker, or any device that trips on "overload" or excessive current.  The purpose is if something fails and the current rises,  the ground wire helps get that information to the breaker or whatever safety device, and send this high current more often to breakers than anything,  so the rise in current is detected as quickly as possible.

That in turn,  trips the breaker as fast as possible  versus a bunch of resistance in the way to slow the fault signal back to the protective device,  

It used to be [as you most likely know]  a 220 appliance was fine with just three wires,   your red and black   which between the two are 220 volts and between each to white or neutral are 110-120 volts]

The white neutral which is actually also ground,  was fine for three wire connections to appliances,  but for a decade or better, the new rule is to have a dedicated ground,  with the three power leads so the neutral was no longer the only ground path.

All existing older three wire systems were grandfathered and deemed OK to use, but replacement of the appliance required the feed be changed from three to four wire,      

From the info you sent,  I cannot tell what kind of type of relay you are using and in what configuration.

Actually for a pump starter one option should be to not use the white,   the pump motor only wants to see 220 or whatever the higher voltage is,   it used to be everything was 110 volts  dual was 110 /  220    anymore,  the "high" option is often 230/240   and the low half of that.


So if this is a fairly uncomplicated breaker to relay to pump,  and the pump is 220,  then you simply need to get 220 to the pump,    then run your dedicated earth ground from breaker to frame of any device in the circuit,  and the white is not needed.

Only if you need to "split" out or off 110 for control voltage would you need the white to get 110     you would NOT want  to use the 110 you will measure from black to ground,  as a power connection.

So to answer basic as the question and keeping it simple,   red and black are your power leads,  ground is ground  [unswitched]  ground is always continuous,   switching 220 or the black and red is fine,    through whatever type of relay you have,   


Remember that motors draw in the range of 4 to 10 times full load current on start up,  with no load,   everytime a motor starts it uses the max inrush current,   load has no effect,  OTHER THAN  if it is a heavier load than the rating of the motor,   then the load will matter because it will try and hold the motor in that very high inrush current period on start up,   past that  it just makes no difference,  each start creates this inrush  which again is 4 to 10 times full load rating,        the reason for that is the magnetizing power needed to form the electromagnets of the windings,  saturate the laminations,  and develop magnets strong enough to create rotation, and start the motor.

This is why sizing of motors and feed wire sizes are critical,     and you need to limit the amount of stops and starts on any motor,    air compressors the bigger the holding tank the better,   a pump if there is some sort of holding tank or supply container,  that decreases the need for more motor startups,   ALL motors have a max allowable number of starts per hour and that number is effected by the variance if any of the supplied voltage compared to the nameplate rating,   if you have a higher voltage supplying whatever device, the starting current could be higher,  and the number of starts should be reduced to match     

The number of starts allowable is to allow the build up of heat in the laminated steel, and the rotor, and the entire motor,    too many starts per period of time,    [normally rated in starts per hour]      

When an application requires many stops or reversals, per hour, it is best to soft start the motor by reducing the start voltage,  using part winding starting,  many different starting methods to keep that inrush current low as possible,       and in that the supply conductors need to be sized accordingly    an application that just has to use a max amount of starts and stops is always better off with larger conductors feeding the motor.

But back to your relay,   if you need the 220 then you switch the red black which is 220,  between them      so the white is not even needed in most cases  just use three wire supply and forget the white or terminating it,      

However this is very generic,  your relay should have a wiring diagram,  or a model number or brand,  say Furnas,   and by the model you should be able to obtain a wiring diagram and manufacturers specific wiring instructions,      


see below   dont click on the advertising arrows look for NEXT button at the top right side of each of three pages:

http://wiki.answers.com/Q/How_do_you_wire_a_pump_start_relay_for_220_volts#page3
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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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Over thirty years with a major repair and sales company, VP of Operations, and former owner of my own specialty repair shops, MEAR Services local to Kansas City Missouri EMR Repair Inc., located in Kansas City Missouri, 2014 sold both businesses to JCI Industries, Lee's Summit Missouri wbabbitt@jciind.com Evaluation and repair of electrical/mechanical apparatus. Electrical and mechanical repairs, trouble shooting including, vibration and balance issues. About.com provides this service, and the huge costs to provide help on about any subject. They provide the servers, the people to vet the experts, costs that would be the same as operating a good sized business, They should be appreciated for what they do, the huge costs and the great help they provide for free, Electric motor questions, can be answered here but there is a dedicated category that has other experts to help and add to a solution. Other common questions, are noises in the walls, breakers tripping, devices not starting or shutting down for no apparent reason, smoke alarms buzzing, thermostat change outs, or sizing wire or needing information for a new project, but anything can be resolved, anything, with enough effort and patience, DIY, with electrical is possible, but in most cases the use of a simple ohm meter or volt meter is needed, they can be purchased at any hardware store for a few bucks. If you have smoke, or smell smoke, don't be writing me, call 911 the Fire Department has no problem looking for smoke smells, better then spraying water on a blazing fire. DO NOT GET CAUGHT INVESTIGATING AND TRAPPED IN A BASEMENT LOOKING FOR A BLOWER FAILING< As to the tip jar, it is up to you, it is appreciated, every expert spends out of pocket that I know, we spend on IP time, computer wear, printing documents, books, and of course our time, but if we prevent a $400 service call, we did well,

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