Term
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Definition
Watt hour constant
The value of 1 revolution of the meter disk,
Expressed in watt hours.
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Term
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Definition
Register Ratio
The number of turns of the 1st gear of the register to cause the 1st (or right hand) dial pointer to complete 1 full revolution which = 10,000 watt hours or 10kwhrs.
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Term
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Definition
Gear Ratio
The number of turns of the meter disk to cause the 1st (or right hand) dial pointer to complete 1 full revolution
= 10,000 watt hrs or 10kwhrs. |
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Term
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Definition
Reduction at Shaft
The ratio between the number of teeth on the 1st gear of the register to the number of entries on the disk shaft. |
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Term
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Definition
Register Constant or Multiplier
Multiplier of the register, due to gearing. |
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Term
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Definition
Transformer Factor
Multiplier of the register, due to CT’s and/or
CT X PT ratios. |
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Term
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Definition
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Shifts current to lag voltage by 60° out of phase(cosine of 60° is .5 or 50%)
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Set board @ nameplate rating with PF switch @ 50% which simulates a 50% load (disk slows 50%)
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Testing how accurately the meter will measure a load with any given PF generated by customer load. Not testing PF of the meter!
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Caused by inductive loads.
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Term
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Definition
E x I x CC x TF
1000
(I = Class of meter)
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Term
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Definition
A Potential-Flux and a Current-Flux, acting on a disk, in a time and space displacement. |
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Term
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Definition
A permanent magnet calibrated at the factory, with the known voltage and amperage to set the speed of the disk. |
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Term
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Definition
Potential-Flux must lag Current-Flux by exactly 90 electrical
degrees at unity power factor to establish max torque of the
disk at any given load power factor. |
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Term
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Definition
| A kilowatt-hour register, counting disk revolutions, displaying them in kilowatt-hours, accomplished at reduction at shaft |
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Term
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Definition
| Industry standard to describe the meter |
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Term
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Definition
| Amperage used with line voltage to set the speed of the disk in 1 hour’s time. (1000Rph 1f) (500Rph Poly f) |
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Term
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Definition
| Rated amperage a meter can continuously handle per phase, provided the meter housing and wiring are adequate |
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Term
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Definition
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Term
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Definition
| A mechanical or solid-state device to prevent reverse rotation of the disk |
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Term
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Definition
| The average rate of consumption over a specific period of time |
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Term
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Definition
| The number of current circuits in series under test |
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Term
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Definition
The inverse of the number of current circuits in series under test.
(Establishes the Kh of individual elements) |
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Term
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Definition
| With applied voltage only, the meter disk makes 1 full revolution either forward or backwards in 10 minutes or less |
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Term
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Definition
An electrical load expressed in watts or kilowatts without a relationship to time. E x I=Watts |
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Term
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Definition
An electrical load expressed in watts or kilowatts times the number of hours it’s used.
E x I x time factor = Kwhr |
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Term
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Definition
| 2 hots and a neutral on a Wye system (ie: FM 12) |
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Term
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Definition
| The unit that provides the driving torque in a watt-hour meter. It includes the Potential-Coil, the Current-Coil and the related framework to provide a magnetic flux or path |
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Term
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Definition
| In a system of N-conductors, N-1 metering elements properly connected, will measure power and/or energy consumed, provided that all potential coil(s) have a common connection in which no current circuit(s) are connected. |
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Term
| Revolutions of Standard Formula |
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Definition
Kh x Cal Constant x revs
.6 x V/120 x amps/5
(.6 = Kh of standard) |
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Term
| List 3 rules of a right triangle |
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Definition
1- Must contain a 90 degree angle
2- All 3 angles must = 180 degrees
3- Hypotenuse is always the longest side, always C
4- Reference angle establishes the adjacent |
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Term
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Definition
(c2 = a2 + b2) or (b2 = c2 - a2) |
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Term
COLD SEQUENCE METERING
(3rd 6 Month Written Test)
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Definition
A current limiting fuse disconnect ahead of the meter, located on the same wall as th meter within 2 feet of the meter.
(Cordova's definition)
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Term
HOT SEQUENCE METERING
(3rd 6 Month Written Test)
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Definition
The electric meter is connected directly to the service conductors without the use of a fault-current limiting disconnect or meter safety-switch device between the electric meter and the supply source.
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Term
HIGH-LEG
(Wild or Power leg)
(3rd 6 Month Written Test)
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Definition
The phase having the higher phase voltage to ground on a 4-wire delta-connected service, where the midpoint of one phase winding is grounded.
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Term
SERVICE MAST
(3rd 6 Month Written Test)
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Definition
The service mast is the conduit containing the service-entrance conductors where the point of attachment and the connection between the service drop and the service-entrance conductors is located above the roofline. The conduit extends to a point, and the weather head is located, above the roof eave. The conduit passes through the eave of the building or extends past the roofline without passing through the eave. The means of attachment is attached to the service mast. |
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Term
SERVICE RISER
(3rd 6 Month Written Test)
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Definition
The service riser is the conduit containing the service-entrance conductors where the point of attachment and the connection between the service drop and the service-entrance conductors is located on a pole or below
the roofline of the building being served. The conduit extends to a point, and the weather head is located, below the roof eave. The means of attachment is secured to the pole or building and is not attached to the service riser. |
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