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Anonymous Poster #1

Fault Would Occur or Not

03/18/2011 6:16 PM

If one appliance(like water pump) is supplied from two different power points at home(which are having same source) what would happen
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TonyS
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#1

Re: fault would occur or not

03/18/2011 6:29 PM

Someone would be bound to pull one plug and get killed by the live pins being fed from the other socket.

To be blunt it's a stupid idea.

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cuba_pete
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#5
In reply to #1

Re: fault would occur or not

03/18/2011 7:41 PM

Another good point. I though the guy was going for the theoretical, not actual practice. Maybe he found it that way...
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jack of all trades
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#8
In reply to #1

Re: fault would occur or not

03/20/2011 2:54 PM

To be blunt it's a stupid idea.

And has also killed at least one person in New Zealand in recent years.

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cuba_pete
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#2

Re: fault would occur or not

03/18/2011 6:29 PM

Nothing extraordinary. You effectively double the size of the conductor. It's illegal under the NEC, but not much would happen unless the circuit overloaded.
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jk
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#3
In reply to #2

Re: fault would occur or not

03/18/2011 7:16 PM

Unless ofcourse the "source" is the load centre but the two circuits are on different phases!

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cuba_pete
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#4
In reply to #3

Re: fault would occur or not

03/18/2011 7:39 PM

AH! Touche! That's an excellent point. Sometimes the obvious eludes me.
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jack of all trades
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#9
In reply to #3

Re: fault would occur or not

03/20/2011 2:55 PM

Also another dangerous modification that has been tried and has result in the death of at least one person in New Zealand in recent years.

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TonyS
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#6

Re: Fault Would Occur or Not

03/19/2011 5:39 AM

The guys talking about two power points in the home. I assume he got a pump that is rated higher than the socket rating.

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msamad
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#7

Re: Fault Would Occur or Not

03/19/2011 10:52 AM

This is strictly not recommended unless you use the transfer switch with the applicable protection system.

The primary reasons for not doing this are:

(1) If you want to stop the motor and disconnect one source, other source remains connected.

(2) Each of the source point is fed back from the other source from the common connection point.

(3) Motor is fed by two different sources and the protection system will not operate even the motor draws overloaded current because the motor current is shared by two sources.

(4) Even the main source is same; the two different power points may have different voltage level due to the differences in voltage drop in the circuits from the main source to these points. Connecting these two points will result excessive current flow in the upstream circuits and the cables will be overloaded. The protection system may also operate causing loss of power. With this connection, you are basically paralleling the sources. The parallel path may have different resistance in the path and will impact the sharing of current flow.

These are all safety related issues and it is never recommended.

- MS

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