different gauges in one circuit?

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  #1  
Old 03-17-11, 05:20 PM
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different gauges in one circuit?

my son has aquired a property with a well in a small outbuilding that was is serviced by a number 10 undrground wire about 140 feet long. this wire was running the 3/4 horse power motor on the pump but was only hooked up as 110 volts and was on a 30 amp breaker. I have since changed the pump to a 1/2 horse running on 220 volts. now in the pump house i have done something that is likley not legal? and am wondering if i should go to the expense of a samll 4 breaker service panel or can i run it this way

the number 10 wire goes into a 4 inch wide by 2.5 deep round box and then a number 12 wire goes to teh pump (220 volts) also on the black from the number 10 is a number 14 to a light and on the red from the number 10 is a 14 to a receptical Should i change the breaker in the service panel for the numbe 10 wire feeding the pump house to a 15 or 20 amp breaker. I will have a small micro furnace (heater) plugged into the receptical in the winter months. The pump guy told me the pump motor would only draw about 7 or 8 amps on start up, the heater i am not sure. i was thinking a 20 amp to allow for some line loss but i am unsure if i can have nubmer 14 wire in this configuration (or if i can split off the main feed to the pumphouse this way in the first place) some advice (other than calling a pro, as my son can not afford this right now) would be greatly appreciated

PS the pump is wired with a plug on it and a new 220 volt receptical so it can be disconnected in teh pumphouse so from the round box there is a redeptical fo rthe pump, a 110 receptical for the heater and a light switch and one 60 watt light
 
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  #2  
Old 03-17-11, 05:38 PM
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Lighting and general use receptacles are prohibited from being served by 30 amp circuits. They are limited to 20 amp max.

You say you have switched to 240 volt motors. What did you use for the second 120v leg to the motor? If you are now using the white as a hot leg you do not have a neutral to the pumphouse and cannot use any 120v appliances.
 
  #3  
Old 03-17-11, 06:30 PM
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the wire from the main panel is 10/3 red black and white. receptical is on black feed and light is on red feed with shared neutral 220 motor on pump is 1/2 horse . the original wire from the house panel has always been 10/3 but only one the black and white was ever used and it was wired worse than what i have done. when i first went int he pup house the main feed had a 3 prong plug on it with the white, black and ground being used (the red was cut off outside the plug) then this plug was plugged into a duel receptical and the pump (110 volt) was plugged into the other side of the receptical and another receptical and a light were wired out from ack stabbing the first receptical. i was in the pump house looking around and discovered this backwards wiring when i unplugged the 10/3 wire and the lights went out. i am not sure why he had a 30 amp breaker unless with only having a 3/4 horse 110 motor he was maybe blowing lesser breakers. That is why i went to 220 volts i figured lesser amps and i could drop down in breaker size?
 
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Old 03-17-11, 07:10 PM
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As Pcboss said you can't run the 120v general purpose circuits on a 30 amp breaker. Assuming you have a ground in that 3-conductor cable you can install a subpanel as you suggested.
 
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Old 03-17-11, 07:16 PM
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Originally Posted by ray2047 View Post
As Pcboss said you can't run the 120v general purpose circuits on a 30 amp breaker. Assuming you have a ground in that 3-conductor cable you can install a subpanel as you suggested.
would i ok to just use a lower amp breaker the heater is 900 watts (i think that is about 11 amps) and the pump guy told me 6 or 7 for the pump. would a 20 amp be ok? if not than it looks like he spends the money on a small sub panel

yes the feed is red, black, white and bare ground

one more question, if i install the small sub panel do i need to drive a ground rod also or ground back to the main panel is good?
 

Last edited by billie_boy; 03-17-11 at 07:43 PM.
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Old 03-18-11, 05:25 AM
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As the multi-wire branch circuit feeding the pumphouse is counted as one circuit you do not need the ground rod.

You can run new smaller gauge wiring to the lights and receptacle as they will have a properly sized breaker in the subpanel.
 
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Old 03-18-11, 05:46 AM
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thank you very much. a new panel will be in next months budget
 
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Old 03-18-11, 06:28 AM
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My answers are based on the NEC, not the CEC. you may want to call your building inspection department about the ground rod.
 
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Old 03-19-11, 11:47 PM
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Let me speak up real quick this will change the whole thing a bit where the pressure switch is located in the house or at the pump house ?? that will affect the whole arrangement what you need to do with it.

Let us know once the pressure switch located then we can go from there.

Merci.
Marc
 
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Old 03-20-11, 02:13 PM
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Originally Posted by french277V View Post
Let me speak up real quick this will change the whole thing a bit where the pressure switch is located in the house or at the pump house ?? that will affect the whole arrangement what you need to do with it.

Let us know once the pressure switch located then we can go from there.

Merci.
Marc
pressure switch is at the motor in the pump house.. 10/3 coming to pumphouse (right now is a double 30 amp breaker) ((i wish to change to double 20 if possable)) in a 3.5 inch x 2 inch deep round box the wires are spliced as follows- red from 10/3 is wire nutted with white from pressure switch and black from light. Black from 10/3 is wire nutted with black from pressure switch and black from 110 receptical. white from 10/3 is wire nutted to both whites from light and receptical all bare grounds are wire nutted and grounded to box

the pressure switch is on the motor at the pump and both 110 lines hook to it there

i am under the understanding now that i need to feed the 10/3 into a small panel (i seen one at the store that held 4 breakers) when i get this panel can i leave the 30 amp breaker to feed it and then use a double 15 for the 220 pump and a single 15 for the one 60 watt bulb and the 900 watt heater?
 
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Old 03-20-11, 03:24 PM
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i am under the understanding now that i need to feed the 10/3 into a small panel (i seen one at the store that held 4 breakers) when i get this panel can i leave the 30 amp breaker to feed it and then use a double 15 for the 220 pump and a single 15 for the one 60 watt bulb and the 900 watt heater?
That would be the best way.

A larger box would be ok also. Price wise you may be able to find a larger size box with breakers included in the price for less then a smaller box no breakers included when you factor in buying breakers for the smaller box.

You will need at least one 8' ground rod. If the piping is metal you will need to ground both to the pipe and the ground rod.

The box will probably not include a ground bar. You will need to buy and install a ground bar in that case. You do not bond the neutral bar to the case. If it is bonded you remove the bonding screw or strap.

If you continue to plug in the pump instead of hard wire be sure the pump receptacle is a 6-15r or a L6-15r.
 
  #12  
Old 03-20-11, 04:07 PM
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Originally Posted by ray2047 View Post
That would be the best way.

A larger box would be ok also. Price wise you may be able to find a larger size box with breakers included in the price for less then a smaller box no breakers included when you factor in buying breakers for the smaller box.

You will need at least one 8' ground rod. If the piping is metal you will need to ground both to the pipe and the ground rod.

The box will probably not include a ground bar. You will need to buy and install a ground bar in that case. You do not bond the neutral bar to the case. If it is bonded you remove the bonding screw or strap.

If you continue to plug in the pump instead of hard wire be sure the pump receptacle is a 6-15r or a L6-15r.
thanks ray..the plug is rated for 220 (it said that on the pack) the prongs that carry current are both slotted horizontal and the plug and the receptical came as a set.
 
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Old 03-20-11, 04:29 PM
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thanks ray..the plug is rated for 220 (it said that on the pack) the prongs that carry current are both slotted horizontal and the plug and the receptical came as a set.
It is not just the voltage rating but the amp rating also that is important.

You should have one of thse configurations:

 
  #14  
Old 03-20-11, 07:40 PM
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The 6 space subpanel will work for this useage just make sure you have grounding conductor there { Bare or green } and also sink a ground rod as well but few case I can use the well casing as ground rod as well.

{ just a note once you get over 6 space breaker slot then you will have to have backfeed main breaker or factory installed main breaker in there for detached buildings for attched buildings it will varies a bit }

Merci.
Marc
 
  #15  
Old 03-21-11, 09:04 AM
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If your well casing is metal, you can run a ground wire to that instead of a ground rod.
 
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