Time Clock as a disconnect

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charlie b

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I would say "no." If the devices controlled by this clock will turn back on when the clock reaches its next set point, then the clock did not disconnect the devices from the source.
 

M. D.

Senior Member
I would tend to think no . The clock is "utilization equipment " and as such, it would require a switch itself. 680.12 (2005)
 

LarryFine

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jwelectric said:
What if the timer has an off toggle switch?
If a toggle ahead of the timer, yes. As part of the timer, no (unless the switch is marked for use as a disconnect.)
 

iwire

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I agree it should not be used as one.

I am not so sure there is any NEC section to prevent it.

Usually they are indicating (marked on and off) and can disconect the ungrounded conductors.

Does being a controller prohibit an item from being a switch as well?
 

petersonra

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Northern illinois
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engineer
Pierre C Belarge said:
Does the NEC/UL permit a timeclock to be used as a means of disconnect, such as at pools?

The code does not clearly define disconnecting means to specifically exclude the possibility that an automatic action (such as a timing motor) may cause reconnection.

maybe the definition should be changed to indicate a disconnecting means must provide that a manual operation can disconnect power and when a manual operation is used to disconnect power, a manual operation must be employed to reconnect.
 
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LarryFine

Master Electrician Electric Contractor Richmond VA
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Henrico County, VA
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Electrical Contractor
iwire said:
Usually they are indicating (marked on and off) and can disconect the ungrounded conductors.
Remember, though, that the timer motor is still energized during a manual off. That it can turn back on at an inopportune moment would be my concern. Locking out is a must.
 

George Stolz

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LarryFine said:
Remember, though, that the timer motor is still energized during a manual off. That it can turn back on at an inopportune moment would be my concern. Locking out is a must.
The thing is, though, no means of locking out is required. Only a disconnect.

The most compelling argument against it is that the clock is utilization equipment. If it's on when the switch is off it's not disconnected. Now, is the clock required to have a disconnect? According to 680.12, I would say "yes."
 

celtic

Senior Member
Location
NJ
I recall reading something about disconnects and there intended purpose....does this ring a bell with anyone?

I'll try and dig up the reference....leave a light on, it might take awhile,
 

jwelectric

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Location
North Carolina
I have a time clock that has a toggle switch on the side that turns off all ungrounded conductors that are entering the clock.
When the switch is off the clock is off. When the switch is off the load side of the clock is off.

Would this clock fulfil the requirements of 680.12?
 

iwire

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LarryFine said:
Remember, though, that the timer motor is still energized during a manual off. That it can turn back on at an inopportune moment would be my concern. Locking out is a must.

Thanks for clearing that up Larry, I had no idea how a time clock worked. :D

Now can you find a code section to support your valid safety concern?
 

ronbannon

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nj
I had a post simular to this. I spoke with NFPA and got a clarification.
Time clock if rated for the motor and has a lever to turn it off can be used as a disconnect for the pool motor, But they also added that in 430.101,102
the timer is now a motor controller and also needs a disconnecting means to ahead of it. Sorry for any miss spelled words haven't found spell check.
 

M. D.

Senior Member
Iwire , 680.12 "One or more means to disconnect all ungrounded conductors shall be provided for all utilization equipment other than lighting......."

Key words; all utilization equipment The timer needs a disconnect as far as I can tell just for the fact that it uses electricity, as well as the reasons Ron pointed out.
 
I believe the disconnect could be on the load side of the time clock, as long as it is disconnecting the load required to be disconnected. It would not make sense to install the disconnect ahead of the clock, as the timer would require resetting.
 

M. D.

Senior Member
Pierre , I have changed a few time clock motors over the years, as I'm sure many of us "resi" electricians have, it sure is nice when there is a disconnect. Most of the time the homeowner is not home and the house is locked , whether you asked them to leave it open or not.

680.12 says "all utilization equipment" the clock uses the flow of electricity ,does it not? It is also a controller in my opinion.
I wear a watch so resetting the clock is a small price to pay for not getting fried.
The homeowner can use the manual override switch to preform standard pool functions , the clock won't be disconnected.
The switch is for me , when the clock needs to be serviced and they do.
 
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