Home > Flashcards > Print Preview
The flashcards below were created by user
electric
on FreezingBlue Flashcards. What would you like to do?

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

Define 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.

Define 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.

Define 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.

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

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

Define Drive
A PotentialFlux and a CurrentFlux, acting on a disk, in a time and space displacement.

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

Define Lag
PotentialFlux must lag CurrentFlux by exactly 90 electrical degrees at unity power factor to establish max torque of the disk at any given load power factor.

Define Record
A kilowatthour register, counting disk revolutions, displaying them in kilowatthours, accomplished at reduction at shaft

Define Form
Industry standard to describe the meter

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

Define Class
Rated amperage a meter can continuously handle per phase, provided the meter housing and wiring are adequate

List the 6 parts of an ElectroMechanical Meter
Base, Meter Disk, Kilowatt Hour Register, Permanent Magnet, Stator, Cover

List the 3 major meter types
 A Baseelectromechanical
 Socketelectromechanical
 SocketSolid state

List the 6 major parts of a Solid State meter.
 Base
 Cover
 Digital Display
 CT's or Hall Effect Pickups
 Circuit Board
 Current Coils

What are the 4 basic EM meter functions?
Drive, Drag, Lag, Record

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

Define PKh
Primary Watthour Constant
The Watthour Constant x Transformer Factor

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

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

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

Define 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 Stator (Meter Element)
The unit that provides the driving torque in a watthour meter. It includes the PotentialCoil, the CurrentCoil and the related framework to provide a magnetic flux or path

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.

Test Amps Formula
 E x I x CC x TF
 1,000 Rph for single phase
 500 Rph for Polyphase

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

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





Power Formula
Volts x Amperes (or) E x I

Energy Formula
Volts x Amperes x Time (or) E x I x Time

Demand Formula
 E x I x CCx TF 1000
 where “I” is equal to the amperage
 on the meter under test

Draw a single phase delta bank and secondary lines

Draw and connect FM1/FM2/FM12 meters abase and socket

Form Designation
The industry wide standard to describe the meter construction and wiring.

Transformer Factor Formula
 TF = 10,000 x Kr
 Kh x Rr x Rs
 (or)
CT ratio x PT ratio = TF

List the 4 basic Solid State meter functions
 Sample
 Calculate
 Convert
 Display

Define Sample
Sample: samples current & voltage at the CTs and meter stabs

Define Calculate
Calculate: Multiplies current & voltage in phase to calculate watts being used

Define Convert
Converts data into a digital signal to be sent to the digital display

Define Display
Displays consumption in Kwhrs or KW for billing purposes

Define Current Circuits (CC)
The number of current circuits in series under test

Define ABase Meter
An electromechanical meter where the line and load side conductors are physically connected to the bottom of the meter

Define Socket Type Meter
A meter designed to plug into a preexisting, prewired meter housing designed for the meter type and load.

Define Creep
With applied voltage only, the meter disk makes 1 full revolution either forwards or backwards in 10 minutes or less.

Network System
2 hots and a neutral connected to a wye system

Define Detent
A mechanical or solid state device used to prevent reverse rotation of the meter disk

Be able to use all formulas to solve equations.

What is a segment check?
Every pixel is lit up at once to test full functionality of the display


Pythagorean's Theorem
a^{2} + b^{2} = c^{2}

Define ERT
Encoder, Receiver, Transmitter

Be able to explain a customers electrical use vs what the meter measures on a FM1 & FM2

