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Name the 3 major types of meters.
 Electromechanical Abase
 Electromechanical Socket
 Solid State Socket

Name the major parts of an electromechanical meter.
Cover, Base, Stator, Disk, Register, Permanent magnet

Name the major parts of a Solid State meter
Cover, base, current coils, circuit board, digital display, CT's or Hall effect pickup

Define Drive
A voltage flux and a current flux acting on the meter disk in a time and space displacement.

Define Drag
A permanent magnet calibrated at the factory with a known amperage and voltage to set the speed of the meter disk

Define Lag
Potential flux must lag current flux by exactly 90 electrical degrees at unity power factor to establish maximum torque of the meter disk at any given load power factor

Define record
A kilowatt hour register counting meter disk revolutions and displaying them in kilowatt hours. This is accomplished at the reduction at shaft.

What are the 4 basic functions of an electromechanical meter?
Drive, Drag, Lag & Record

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

What are the 4 basic meter functions of a solid state meter? Define each.
 Sample: Samples current and voltage at the CT’s and meter stabs
 Calculate: Multiplies current and voltage, in phase, to calculate watts being used
 Convert: Converts data into a digital signal to be sent to, and displayed, by the digital display
 Display: Displays load in Kwhrs or KW for billing purposes

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 or CT X PT ratios.

When a meter is first energized, what first appears on the meter display?
Segment check





Draw a pictoral and schematic view of a single phase delta service and include:
connections to secondary lines
label voltages at the secondary lines
draw and connect FM1/FM2/FM12 sockets

Using the TA formula determine K_{h} of meters show work

What is the test amps formula?
 E x I x CC x TF
 1000rph (single phase)
 500rph (poly phase)

What is the formula for Ohm's Law?
E=I x R

What is the formula for Pythagorean's Theorem?
a^{2} + b^{2} = c^{2 }

Define ERT and what it does?
 Encoder Receiver Transmitter
 Allows electric meters to be read remotely

