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K_{h}
 Watt hour constant
 The value of 1 revolution of the meter disk, Expressed in watt hours.

R_{r}
 Register Ratio
 The number of turns of the 1^{st} gear of the register to cause the 1^{st} (or right hand) dial pointer to complete 1 full revolution which = 10,000 watt hours or 10kwhrs.

R_{g}
 Gear Ratio
 The number of turns of the meter disk to cause the 1^{st} (or right hand) dial pointer to complete 1 full revolution = 10,000 watt hrs or 10kwhrs.

R_{s}
 Reduction at Shaft
 The ratio between the number of teeth on the 1^{st} gear of the register to the number of entries on the disk shaft.

K_{r}
 Register Constant or Multiplier
 Multiplier of the register, due to gearing.

TF
 Transformer Factor
 Multiplier of the register, due to CT’s and/or CT X PT ratios.

Test Amps
Amperage used with line voltage to set the speed of the disk in 1 hour’s time. (1000Rph 1phase) (500Rph Poly phase)

PKh
Watthour Constant x Transformer Factor

Demand
The average rate of consumption over a specific period of time

Calibrating Constant
The inverse of the number of current circuits in series under test.
(Establishes the Kh of individual elements)

Power
An electrical load expressed in watts or kilowatts without a relationship to time. E x I=Watts

Energy
An electrical load expressed in watts or kilowatts times the number of hours it’s used.
E x I x time factor = Kwhr

Define Cold Sequence Metering
The utilization of a fault current limiting disconnect device between the electric meter and the supply source, adequate to protect meters from excessive fault currents.

Detent
A mechanical or solid state device to prevent reverse disk rotation.

Network
2 hots and a neutral on a wye bank

Creep
With applied voltage only, the meter disk completes one full rotation either forward or backwards in 10 minutes or less.

Blondel's Theorum
In a system of Nconductors, N1 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.

What does “AMR” stand for?
What does it mean?
 Automated Meter Reading.
 A method of reading electric registers.

Register Ratio Formula
 10,000 x K_{r}
 TFxK_{h}xR_{s }

Watts Formula
 K_{h }x 3600 x revs
 Time in seconds





Define Hot Sequence Metering
The electric meter is connected directly to the service conductors without the use of a faultcurrent limiting disconnect device between the electric meter and the supply source.

Define Data Pulses
Output pulses (KYZ) generated by the electric meter for use by the customer.

Define High (Wild) Leg
The phase having the higher phase voltage to ground on a 4wire deltaconnected service, where the midpoint of one phase winding is grounded.

Draw and label FM1,2,12,14,15,16,5,6,8,9 socket and Abase meters

Define Voltage Transformer
An instrument transformer intended for use in the measurement or control of a circuit and designed to have its primary winding connected in parallel with the circuit

Define Voltage Unbalance
Maximum voltage deviation from average voltage.

Define Service Mast
The service mast is the conduit containing the serviceentrance conductors where the point of attachment and the connection between the service drop and the serviceentrance conductors is located above the roofline. The conduit extends to a point, and the weatherhead is located, above the roof eave. The means of attachment is attached to the service mast.

Define Service Riser
The service riser is the conduit containing the serviceentrance conductors where the point of attachment and the connection between the service drop and the serviceentrance conductors is located on a pole or below the roofline of the building being served. The conduit extends to a point, and the weatherhead 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.

Define Point of Attachment
The point at which the servicedrop conductors are attached to a building or other structure.

Define Closed Loop
A temporary unmetered electric service.

What is the max distance the point of attachment shall be located from the weatherhead?
24"

What is the minimum length for a residential service entrance conductor?
24"

What is the minimum length for a commercial service entrance conductor?
36"

What is the vertical clearance from ground for servicedrops over spaces and ways to subject to pedestrians?
12 feet

What is the vertical clearance from ground for servicedrops over driveways, parking lots, and alleys?
16 feet

What is the vertical clearance from ground for servicedrops over other land traversed by vehicles?
16 feet

What is the max height of the point of attachment from final grade?
24 feet

How many days max can the company grant permission to close a loop
7 Calendar days

What size and material is required for service masts?
2” minimum GRC

Can conduit couplings be installed above the roofline
No

What is the max total amps rating of the main disconnect for a 200 amp continuous duty rated meter socket.
 250 amps
 (400 amps max for a CL320 rated housing)

Can phone loops, cable TV conductors, grounding clamps, etc. be attached to the service mast.
No, only the Company’s power servicedrop conductors shall be attached to a service mast.

Can line and load conductors are permitted in the same raceway or conduit.
No

When are junction boxes, conduit fittings (e.g. LB’s), or other devices allowed?
Only with specific written approval from the Company’s local Electric Meter Department.

When can the Company authorize a closed loop on new electrical services.
Never on NEW services

What is the maximum length of #2 triplex service drop conductor to residential and commercial installations?
90 feet

List 3 of the 5 rules for solving a right triangle
 Sum of the three angles in a triangle is always 180o
 The right angle is 90o by definition
 The hypotenuse is always the side opposite of the 90o angle
 The opposite side is the side across from the angle given
 The adjacent side is the side that makes up the given angle in combination with the hypotenuse

Identify or name all three sides of a right triangle.

What is Pythagorean's Theorem
(use to solve problem)
c2 = a2 + b2

Using the basic laws of Trigonometry solve/prove that the wild (high) leg is 208 volts from center tap neutral on a 120v/240v delta system.

Using the basic laws of Trigonometry solve/prove that the phasetophase wye voltage is 208 volts.

Draw and label the following banks both pictoral and vector drawings:
  Open Delta 3W3phase
  3W3phase closed Delta
  4W3phase Wye
  4W3phase Delta

