tap a tap
- Thread starter sleepy
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Re: tap a tap
I don't completely understand what you are asking, but maybe this will help:
The wires on the secondary side of a transfomer are usually taps untill they get to a fuse or circuit breaker on the secondary side.
For the few exceptions, see 240.21(C)(1).
Steve
I don't completely understand what you are asking, but maybe this will help:
The wires on the secondary side of a transfomer are usually taps untill they get to a fuse or circuit breaker on the secondary side.
For the few exceptions, see 240.21(C)(1).
Steve
- Location
- Massachusetts
Re: tap a tap
Sleepy, Are you asking if you can have two disconnects on the secondary side of a transformer?
Yes you can, there are two ways to go.
The transformer must have primary side protection this could be 125% or 250% of primary current.
If the primary protection is set at 125% you may connect two or more disconnects that total more than the transformer is rated.
If the primary protection is set at 250% the secondary overcurrent device shall be permitted to consist of not more than six circuit breakers or six sets of fuses grouped in one location. Where multiple overcurrent devices are utilized, the total of all the device ratings shall not exceed the allowed value of a single overcurrent device. If both breakers and fuses are utilized as the overcurrent device, the total of the device ratings shall not exceed that allowed for fuses.
Look at Table 450.3(B) and the notes to that table this tells you the requirements for transformer protection.
For the conductor protection requirements look at
240.21(C)(2) for up to 10' or 240.21(C)(6) for up to 25'.
[ February 09, 2004, 03:50 PM: Message edited by: iwire ]
Sleepy, Are you asking if you can have two disconnects on the secondary side of a transformer?
Yes you can, there are two ways to go.
The transformer must have primary side protection this could be 125% or 250% of primary current.
If the primary protection is set at 125% you may connect two or more disconnects that total more than the transformer is rated.
If the primary protection is set at 250% the secondary overcurrent device shall be permitted to consist of not more than six circuit breakers or six sets of fuses grouped in one location. Where multiple overcurrent devices are utilized, the total of all the device ratings shall not exceed the allowed value of a single overcurrent device. If both breakers and fuses are utilized as the overcurrent device, the total of the device ratings shall not exceed that allowed for fuses.
Look at Table 450.3(B) and the notes to that table this tells you the requirements for transformer protection.
For the conductor protection requirements look at
240.21(C)(2) for up to 10' or 240.21(C)(6) for up to 25'.
[ February 09, 2004, 03:50 PM: Message edited by: iwire ]
- Location
- Illinois
- Occupation
- retired electrician
Re: tap a tap
sleeply,
Neither of those items are taps. Look at defintion of a tap conductor in 240.2.
Don
sleeply,
Neither of those items are taps. Look at defintion of a tap conductor in 240.2.
Don
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