Hi, I wondering how to call this system, the 3 phase main conductors in a overhead riser are entering to an exterior junction box and connected to a device like a (KW reader) then small amount of # 10 AWG are connected to the meter box and utility meter. I need to connect a new meter to this service but have no idea how this type of system is called. Thank you !!
FP&L Miami FL. Old building, main power lines are connected to a reader in a box
- Thread starter O'donisR
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chris kennedy
Senior Member
- Location
- Miami Fla.
- Occupation
- 60 yr old tool twisting electrician
Thats called CT metered. Got pics? Why do you need to install new meter?
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Like Chris said - it is most likley CT type metering. Common on some services between 200 and 400 amps and almost all you will ever find on services over 400 amps where entire load is metered by a single meter.
Are you wanting to add additional service capacity, or maybe separately metered supply? More information is likely a help for us to be able to answer your questions.
Are you wanting to add additional service capacity, or maybe separately metered supply? More information is likely a help for us to be able to answer your questions.
chris kennedy
Senior Member
- Location
- Miami Fla.
- Occupation
- 60 yr old tool twisting electrician
Not so much around here any more. We have been installing 600A 1? and 3? services for the last few years with no CT's.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Around here POCO's don't want their guys installing or pulling meters with the kind of fault currents that will typically be available in those cases, and you don't really see too many self contained metering over 200 amps except for 320 bases at times.
I did one a few years ago - 400 amp 277/480 service. POCO asked for a bolt in meter base. Hooked it up they put in meter - no problem. Sometime later I was working at same place and noticed they pulled all the guts out of the meter base blanked the opening for the meter and installed CT's inside the enclosure and placed CT meter off to the side of it.
Their meter requirements that they publish indicated that they typically want CT metering for this and I was suspicious about it when they told me they wanted the bolt in meter. Someone must have made a wrong decision there.
Another POCO that has a high number of 200 amp 277/480 services for irrigation wells in the area wants the meter and disconnect on the opposite side of pole from where the primary fuses are. That way if their linemen are installing fuses and something blows up in the meter or disconnect they are not standing directly in front of it. Same POCO does not install or remove that meter from socket without primary fuses removed from the circuit.
hillbilly1
Senior Member
- Location
- North Georgia mountains
- Occupation
- Owner/electrical contractor
Cold sequence metering is gaining ground down here, it's been around quite a while up north.
Building owner need to add a meter box to his existing electrical riser, but the Old mete is a CT type metering and I just got tell from the building department (Miami City) that I cannot connect the new meter to the junction box were the CT type metering is connected,what I have to do is remove all the CT system including the old meter box and install two new meters instead. In order to do this, i will use the existing junction box to connect the 2 meters to the service main wires as the picture show. hope you understand my drawing. 
hurk27
Senior Member
- Location
- Portage, Indiana NEC: 2008
Looks good as long as you have the utility and inspectors blessing, but I have a question on the voltages you have listed?
120/240 is a 4-wire delta with a wild leg on "B" phase that will be 208 to the neutral as such the single phase meter will only be able to be connected to the A & C phases.
If you have stated the wrong voltages and in reality you have a 120/208 Y service then you should be good to go.
120/240 is a 4-wire delta with a wild leg on "B" phase that will be 208 to the neutral as such the single phase meter will only be able to be connected to the A & C phases.
If you have stated the wrong voltages and in reality you have a 120/208 Y service then you should be good to go.
chris kennedy
Senior Member
- Location
- Miami Fla.
- Occupation
- 60 yr old tool twisting electrician
Where are the two new main disco's going to be located?
The two disconnects are located back to back and connected to a gutter with main wires from meter.
no, I didn't get the inspector blessing, the main disconnect for the new meter needs to be outside next to the new meter, what inspector recommended was to leave the CT meter and riser as the way it is and add the new meter with his own over head riser and a main disconnect next to the existing CT meter. Thank you
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
What is reasoning for separate meter? If to supply a separate occupancy and if disconnecting means are not required to be grouped together it may be ok, really need to more before I can make that call. If disconnects are required to be grouped together then inspector is creating violations before you even get started by wanting one disconnect in this location and other(s) at existing location.
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