BArmy
Member
- Location
- Jackson Wy
- Occupation
- inspector
A 3 phase 208 200 amp shunt trip breaker being used as a main service disconnect, best location to get the 120 volts to engage shunt?
Shunt breaker as main disconnect
- Thread starter BArmy
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LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
Welcome to the forum.
Generally, any always-hot source supplied by the breaker will do, unless it's rated to be continuously energized.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Just use a 15 amp branch circuit from the panel. What is the purpose of the shunt trip?
This may be a stupid question, but why would someone shunt trip a main? Wouldn’t that negate turning the breaker back on?
Doesn't a shunt trip have to have power to remain closed? If so, wouldn’t the control circuit be after the main?
Doesn't a shunt trip have to have power to remain closed? If so, wouldn’t the control circuit be after the main?
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
It's merely way of tripping it remotely. Once the tripping power is removed, it can be reset manually.
No, a shunt-trip breaker does not need power to stay on. It's basically a standard breaker with a solenoid coil added that activates the trip mechanism. A momentary pulse of power trips it.
Thanks.
Makes sense now.. Don’t ever remember coming across one like that before.
I had in mind something like a contractor with an aux relay.
BArmy
Member
- Location
- Jackson Wy
- Occupation
- inspector
Thanks all for your comments, shunt is because there is 20 town homes (SFD) that require a disconnect on each dwelling and the engineer designed a meter stack system, so each unit gets a service disconnect shunt button on each unit.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
What NEC code section would require this?
BArmy
Member
- Location
- Jackson Wy
- Occupation
- inspector
NEC 230.70(A)(1), A(3) allows remote control, 230.85 signage.
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
Probably a local code, don’t know why they would want individual owners to be able to kill power to the entire complex. I can see maybe a fireman’s switch. Done that on commercial buildings as a local requirement because the main is inside.
BArmy
Member
- Location
- Jackson Wy
- Occupation
- inspector
Shunt only does each single family dwelling, Not entire complex, each dwelling is fed with a 200 amp 3 phase 208Volt breaker.
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
If that’s the case, then probably pull from a house panel, if there is one. Where is the shunt button located? At each unit? If so, then it could be powered from the tenants panel since you have to run two wires back to the breaker anyway.
Tulsa Electrician
Senior Member
- Location
- Tulsa
- Occupation
- Electrician
Three phase to a dewelling.first for me
Tulsa Electrician
Senior Member
- Location
- Tulsa
- Occupation
- Electrician
I could see this if there was no main in the residents panel. I remote would do the trick. Never seen one in a meter pack. A pic would be cool to see.
Tulsa Electrician
Senior Member
- Location
- Tulsa
- Occupation
- Electrician
I would pull it from the panel in dwelling unit, pull with feeder to unit. I take it is all in raceway or MC.
Wonder if a branch circuit can be in the meter pack with feeders/ service conductors. Ummmm
Wonder if a branch circuit can be in the meter pack with feeders/ service conductors. Ummmm
LarryFine
Master Electrician Electric Contractor Richmond VA
- Location
- Henrico County, VA
- Occupation
- Electrical Contractor
Here's a Google Maps link to a pic of one. I know because I have worked there.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Is this shunt trip service disconnect remote from each of the 20 units? If so then how's does it comply with 230.71(A)(1)?
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
I worked on one in the Dominican Republic that had a 400 amp three phase service. 24’ ceiling in the living room, three phase washing machine. Commercial dryers. It was the guy’s vacation home. He said his regular home in Puerto Rico was even bigger!
BArmy
Member
- Location
- Jackson Wy
- Occupation
- inspector
Art 230.70(A)(1) states or inside nearest the pointor the service conductors, the meter Paks are 2 inches off the complex structure in the alley way. All good to go. See you all with any future questions. Thanks and best.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
So the service disconnects are not on each separate structure? If that's the case then each unit is fed by a feeder not SEC's.
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