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Electric Meter
Xcel Energy electric meter apprenticeship
138
Other
Professional
02/25/2011

Additional Other Flashcards

 


 

Cards

Term

Kh

Definition

 

 

Watt hour constant

 

 

The value of 1 revolution of the meter disk,

Expressed in watt hours.

 

Term

Rr

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.

 

Term
Rg
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.

Term

Rs

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.

Term

Kr

Definition

Register Constant or Multiplier

Multiplier of the register, due to gearing.

Term

TF

Definition

Transformer Factor

Multiplier of the register, due to CT’s and/or

CT X PT ratios.   

Term
 Power Factor
Definition
  • Shifts current to lag voltage by 60° out of phase(cosine of 60° is .5 or 50%)
  • Set board @ nameplate rating with PF switch @ 50% which simulates a 50% load (disk slows 50%)
  • Testing how accurately the meter will measure a load with any given PF generated by customer load. Not testing PF of the meter!
  • Caused by inductive loads.
Term

Full Scale

  • Formula (Dual range & Solid State)
  • Reasons for reaching FS
Definition

E x I x CC x TF

      1000 

(I = Class of meter)

  • Tampering
  • Customer using extra load
  • Demand motor burned up
  • Outage on phase running demand motor
Term
FL Adjustment
Definition
  • Located near Permanent Magnet
  • Current fluxes added or cut
  • Affects meter at nameplate rating
  • Screw in- cuts lines of flux/ disk speeds up
  • Screw out- creates braking action, adds flux
Term
LL Adjustment
Definition
  • Shifts saturation plate to oppose or reinforce disk speed
  • Potential Flux obsorbed by Saturation plate
  • Affects FL by 10%
Term

LG 304

Gang Board

Definition
  • Demonstrate Knowledge of equip, theory, and register.
  • Obtain info
  • Inspect
  • Test
  • Calculations
  • Check results
  • Check register for proper programs/indexes
  • Prepare for Shipping
Term

LG 311

3 Phase Special Test

Definition
  • Set up testboard for meter in test
  • Inspect for hazards
  • If no hazard exists, plug in meter
  • Obtain info
  • Test accuracy
  • Test Demand
  • Physically & mathematically prove register/gears
  • Document results
  • Paperwork, emails
Term

LG 354

3 Phase A-base

Definition
  • Set up testboard for meter in test
  • Inspect for hazards
  • If no hazard exists, plug in meter
  • Obtain info
  • Demonstrate Register Functions
  • Initial test
  • Document results
  • Dissassemble, clean, repair
  • Reassemble
  • Perform Demand test
  • Perform Final test
  • Document results
Term

LG 313

A1D

Definition
  • Set up testboard for meter in test
  • Inspect for hazards
  • If no hazard exists, plug in meter
  • Obtain info
  • Demonstrate Register Functions
  • Program Register w/proper constants
  • Perform accuracy test
  • Perform KYZ
  • Prepare meter for Gang Board
  • Document results
  • Term

    LG 317

    DR87

    Definition
    • Demonstrate knowledge of test equip/recorder
    • If new, number and record info
    • If used, clean, remove old leads, plug holes
    • Inspect for damage
    • Repair damage, missing parts
    • Wire in test leads
    • Connect to test board
    • Program
    • Test
    • Check modem
    • Check pulses
    • Prepare for shipping if ok
    • Paperwork
    Term

    LG 318

    LMR

    Definition
    • Demonstrate knowledge of test equip and relays
    • If used, clean, remove old leads, plug holes
    • Inspect for damage, faulty parts
    • Repair damage/parts
    • Wire in test leads
    • Connect to test board
    • Perform check with multi-meter
    • Prepare for shipping, if ok
    Term

    1/2 FS

    • Formula
    • Reasons
    Definition

    FS in Watts/2/CC/TF of old gang board

    Applied Voltage 

    • Demand Accuracy (due to demand register error factor in EM meters, it was desirable to build demand at 1/2 FS instead of the 4% or 2% range)
    • To establish test amps
    • Old gang board TFs: CL200=40 / CL100=20 / CL50=10

    (No mech midrange on solid state)

    Term
    Old Gang Board TFs
    Definition

    CL 200 = TF 40

    CL 100 = TF 20

    CL 50 = TF 10

    Transformer rated = TF 1

    Term
    List 5 Demand Formulas
    Definition

    Knopp board

    Demand

    Watts

    Campbell

    Max Pulse

     

    Term
    Demand Types
    Definition
    • Rolling- highest monthly peak
    • Block- highest 15 min block ave
    • Thermal- uses bi-metal spring 90% efficient (warm time)
    • Cumulative- adds demand peaks
    Term

    Test mode

    Display items

    Definition
    • Time remaining in interval
    • Present KW
    • Max KW

     

    • Max pulses (AID only)
    Term

    Possible Alternate mode

    Display items

    Definition
    • Kwh
    • Max KW
    • Cum KW
    • Normal Kh
    • Interval length
    • Demand reset count
    • Outages

    Meter will still accumulate Kwh/demand

     

    Term
    KYZ
    Definition

    Output pulses from the register for:

    LMR for customer to monitor loads via computer

    DR87 for billing purposes

    Term
    Drive
    Definition

     A Potential-Flux and a Current-Flux, acting on a disk, in a time and space displacement.

    Term
    Drag
    Definition

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

    Term
    Lag
    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.

    Term
    Record
    Definition
    A kilowatt-hour register, counting disk revolutions, displaying them in kilowatt-hours, accomplished at reduction at shaft
    Term
    Form
    Definition
    Industry standard to describe the meter
    Term
    Test Amps
    Definition
    Amperage used with line voltage to set the speed of the disk in 1 hour’s time. (1000Rph 1f)  (500Rph Poly f)
    Term
    Class
    Definition
    Rated amperage a meter can continuously handle per phase, provided the meter housing and wiring are adequate
    Term
    PKh
    Definition
    Watt-hour Constant x TF
    Term
    Detent
    Definition
    A mechanical or solid-state device to prevent reverse rotation of the disk
    Term
    Demand
    Definition
    The average rate of consumption over a specific period of time
    Term
    Current Circuits
    Definition
    The number of current circuits in series under test
    Term
    Calibrating Constant
    Definition

    The inverse of the number of current circuits in series under test.

     

    (Establishes the Kh of individual elements)

    Term
    Creep
    Definition
    With applied voltage only, the meter disk makes 1 full revolution either forward or backwards in 10 minutes or less
    Term
    Power
    Definition

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

    Term
    Energy
    Definition

    An electrical load expressed in watts or kilowatts times the number of hours it’s used. 

    E x I x time factor = Kwhr

    Term
    Network
    Definition
    2 hots and a neutral on a Wye system (ie: FM 12)
    Term

    Stator

    (Meter Element)

    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
    Term
    Self Contained Meter
    Definition

    A meter that does not require the use of CT’s and/or CT & PT’s. The meter is connected directly to the supply source, in series with the customer load.

    (Can handle voltage & current internally)

    Term
    Transformer Rated Meter
    Definition
    A meter that requires the use of CT’s and/or CT & PT ratios, connected to the secondaries of the Instrument Transformer to isolate high current and/or current & voltage
    Term
    Blondel's Theorum
    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. 
    Term
    Current Trasformer
    Definition

    o        Isolates primary current from meter personnel and equipment

    o        Expressed as a fraction- always over “5” (?/5)

    o        Connected in series with the customer load

    o        Meters connected to the secondaries of the Instrument Transformer

    Term
    Potential/Voltage Transformer
    Definition

    o        Isolates primary voltage from meter personnel and equipment

    o        Expressed as a fraction- always over “1” (?/1)

    o        Connected in parallel with the customer load

    o        Meters connected to the secondaries of the Instrument Transformer

    Term
    GE Full Scale Formula
    Definition

    166 2/3  X CL

        Rr

    Register    Multiplier

    classes     of register

        1               1

        2               2

        6               4

    Term
    Pulse Demand Formula
    Definition

    Ke x intervals of hour x max pulses  

                    1000

     

    = KW demand

    Term
    Max Pulse Formula
    Definition

    KW demand x 1000

          Ke x intervals of hour

     

    = Max Pulses

    Term
    Pulse Value Formula
    Definition

    Kh X CT X PT (or TF)   

    Pulses/Rev x 1000

     (used in LMR systems)

     

    Shortcut examples:

     RUGS: Kh x TF

               12,000 (or 24,000)

     

      LMR: Kh x TF

        6,000

    Term
    Test Amps Formula
    Definition

    TA=E x I x CC x TF     

          1,000 Rph for 1f

          500 Rph for Poly f

    Term
    Register Ratio Formula
    Definition

     Rr  = 10,000 x Kr

                        TFxKhxRs   

    Term
    Watts Formula
    Definition

    Kh x 3600 x revs   

    Time in seconds

    Term
    Demand Build-up Formula
    Definition

    E x I x CC x TF           

          1,000

     

     (I = applied amps)        

    Term
     Revolutions of Standard Formula
    Definition

    Kh x Cal Constant x revs

       .6 x V/120 x amps/5

    (.6 = Kh  of standard)

    Term
    % of accuracy Formula
    Definition

    calculated/observed  x 100 = accuracy %

     

    (or Expected/Obtained)

    Term
    Knopp Board Demand Formula
    Definition

     Kh x  intervals in hour  x  revs  

                       1000

     

     

    or  Kh x .4 (cheat)

    (expressed in kilowatts) 

    Term
    Campbell Formula
    Definition
    applied amps/CL x FS = KW demand
    Term
    Applied Amps Formula
    Definition

           Demand x 1000    

    CC X Applied voltage

    Term
    Explain Balance Adjustment
    Definition
    Rough adjustment used to ensure that all stators are applying equal amount of torque on the meter disk.
    Term

    Duration of Alt Mode

    Duration of Test Mode

     

    (ABB/Sentinel)

    Definition

    ABB-   

    Alt mode will reset after 1 cycle

    Test mode must be undone manually

     

    Sentinel-

    Both modes reset after 1 hour

    Term
    FM 1 Nameplate
    Definition

    15a/120V 2W

    Kh 1.8

    Rr 55 5/9

    Term
    FM 2 Nameplate
    Definition

    30a/240V 3Wdelta

    Kh 7.2

    Rr 13 8/9

    Term
    FM12 Nameplate
    Definition

    30a/120V 3W

    Kh 14.4

    Rr 6 17/18

    Term
    FM 14 and FM 16 nameplate
    Definition

    30a/120V 4WY

    Kh 21.6

    Rr 9 7/27

    Term

    4 Main Formulas

    (Shop Staples)

    Definition

    TA

    Watts

    Demand

    FS

    Term
    4 Ways to check for Potential
    Definition

    Feel flux with magnet

    Continuity test with fluke

    Continuity test with Continuity Tester

    Meter disk vibration

    Term
    FM 15 Nameplate
    Definition

    30a/240V 4Wdelta

    Kh 28.8

    Rr 6 17/18

    Term
    FM 5 Nameplate
    Definition

    2.5a/120V 3W

    Kh 1.2

    Rr 166 2/3

    Term
    FM 6 and FM 9
    Definition

    2.5a/120V 4WY

    Kh 1.8

    Rr 111 1/9

    Term

    What are the following expressed in?

    Kh

     

    Ke pulse value

    KYZ pulse value

    P/R

    Demand

    Definition

    Kh = watthours

    Ke = watts

    KYZ = watts

    P/R = watts

    Demand = KW

     

    Term

    Accuracy Limits PUC vs Xcel

     

    FL & LL

    PF

    Demand

    Definition

                 PUC / XCEL 

     

    FL & LL     +/- 2%   /   +/- .5%

    PF           +/- 2%   /   +/- .6%

     

    Demand +/- 1% of FS

    Term

    Sentinal Meterprogrammed with wrong Kh.

     

    Which will be correct?

    Customer Bill?

    Tests?

    Timing?

    Ke/KYZ pulse value?

    Definition

    Customer Bill? Yes, based on E & I only

    Tests? No, pulse based

    Timing? No, pulse based

    Ke/KYZ pulse value? No, pulse based

     

    As Kh value determines pulse values, anything with a pulse will be wrong.

    Term

    ABB Meter programmed with wrong Kh.

     

    Which will be correct?

    Customer Bill?

    Tests?

    Timing?

    Ke/KYZ pulse value?

    Definition

    Customer Bill? No, pulse based

    Tests? No, pulse based

    Timing? No, pulse based

    Ke/KYZ pulse value? No, pulse based

     

    As Kh value determines pulse values, anything with a pulse will be wrong.

    Term

    Sentinel

    Nameplate says Kh 7.2

    Programmed with Kh of 14.4

     

    Will test and KYZ output be fast or slow?

    What would you expect?

     

     

    Definition
    50% Slow
    Term
    Why wont ABB test right unless in test mode?
    Definition

    Because in normal mode, the optical port is configured to communicate with a computer program (different computer language).

     

    In Test Mode, the optic port emits simulated disk revs.

    Term

    Expain the difference between internal and external pulses.

     

    (imput vs output)

    Definition

    Internal Pulses are generated within the meter to store data. (examples P/R of 24 for ABB/ 12 for others)

     

    External Pulses are generated by the customer load (KYZ)

    Term
    What is the Demand Motor RPM?
    Definition

     

     The 1st gear of the demand motor makes 1 rev per minute

    Term
    Name the 6 major parts of an electro mechanical meter.
    Definition

    Base

    Meter Disk

    Cover

    Stator

    Permanent Magnet

    Kilowatthour Register

    Term
    Explain R300
    Definition

    ERT designator on Sentinels

    3 ERTs per meter (the ert serial # on the nameplate and the 2 sequential #s)

     

    Super Raptor Displays: (non-Net)

    ERT1 = Kwh

    ERT2 = KW demand

    ERT3 = Billing Cycle

    Term
    4 Steps to a 3W to 2W FM2 Conversion
    Definition
    •  
      • Open Pot clip after the pot coil and ground in meter housing. (bottom of pot coil)
      • Ground System Neutral in Meter Housing
      • Move the Customer load wire to where the System Neutral was.
      • Insert a jumper capable of handling the customer load on the load side meter terminals.
    Term

    What EM meters set on a

    3W 3f   (L or  D)

     

    (no longer allowed per book)

     

    Definition

    Triplex  -  FM 12 (self contained)

    3W 3f loop - FM 5 (transformer rated)

    Term
    Blue book no longer allows what transformer bank?
    Definition

     

    3W 3f   D  or L

    Term

    What EM meters set on a

    4W 3f   or D

    Definition

    Duplex - FM 1

    Triplex - FM 2, FM 12 single phase

    Quad loop Self Contained

    -FM 15

    Quad loop Transformer Rated

    -FM 8

    Solid state- FM2, FM12, FM16, FM9

    Term

    What EM meters set on a

    Wye System

     

    Definition

    Duplex - FM1

    Triplex - FM12

    Quad loop - FM14, FM16,  TR- FM6, FM9

    3W 3f loop - FM12 w/nameplate of 240, TR - FM5

     

    Term
    What banks can a FM1 go on?
    Definition
    All but 3W 3f 
    Term
    What meters set on an open network 120/240 volt wye system? (rare)
    Definition

    FM1,

    FM12 & FM5 (single phase) 

    Term
    What banks can a FM12 go on?
    Definition

    All, depending on potential rating.

     

    120v - 1fD

    240v - 3W 3f D or Wye

    480v - 480 3W 3f D or Wye

    (Closed or open Delta)

    Term
    What banks can a FM2 go on?
    Definition

    1f D or L

    4W 3f   D or L

    Term
    What banks can electro-mechanical FM14 and FM16 set on?
    Definition
    4W Wye
    Term
    What banks can electro-mechanical FM15 set on?
    Definition
    4W 3f  Dor L
    Term
    What banks can electro-mechanical FM6 & FM9 set on?
    Definition
    4W Wye
    Term
    What banks can electro-mechanical FM8 set on?
    Definition
    4W 3f   D or L
    Term
    What banks can electro-mechanical FM5 set on?
    Definition
    All, depending on potential rating.
    Term

    LG #421

    Set a FM2 Socket Meter

    Definition
    • Verify address
    • Identify line source
    • Open meter socket, inspect for hazards
    • Shut off breakers
    • Verify Blue Book conformity
    • Identify conductors (line,load,neutral) in socket.
    • Check full voltage line side meter socket
    • Check for shorts or load phase to neutral
    • Check for shorts or load phase to phase
    • Visually inspect meter
    • Install meter
    • Perform Service check
    • Install socket cover & meter seal
    • Clean up, complete paperwork
    Term
    Define Primary Voltage
    Definition

    The higher voltage of a transformer

     (ie 15KVA: 13.2kv f and f /7620v f to N) 

    or

    instrument transformer.

    Term
    Define Secondary Voltage
    Definition
    The lower voltage of a transformer or instrument transformer
    Term
    Explain the difference between loads and shorts in regards to safety hazards.
    Definition

    A load will arc (voltage drop)

     

    A short will flash (direct contact between lines with no voltage drop)

     

     

    Never connect a meter under a load or a short!

    Term
    Why must you check phase to phase voltage for 240 if you already verified 120V on all phases?
    Definition
    To ensure they aren't the same phase.
    Term
    Explain the difference between Ground and Neutral
    Definition

    Ground = connected to Earth

    Neutral = returns to the source (transformer)

    Term
    List 3 overhead loop types
    Definition
    • Open loop (2,3 or 4 wire)
    • Spun Secondary (duplex, triplex, etc)
    • Midspan Loop
    Term
    Why do design engineers use open Delta systems at times?
    Definition

    Money.

    Costs less, but can only be open if ampacity allows.

     

    Example:

    Closed Delta- 50KV x 3 = 150kva

                                        1.73 (square root of 3)

    Open Delta- 50KV x 2 = 86.7kva

     

    86.7kva

    150kva   = 57% efficient

                                        

    Term
    What are 3 things to verify regarding load side wires?
    Definition
    • Load wires terminate at a disconnect, not a load (dry pack transformer considered a load)
    • No line & load wires in the same compartment (gutter, etc)---potential for theft
    • If multiple service, each meter connects to correct apartment

    (pg 21 of Blue Book)

    Term
    ATO
    Definition

    Automatic Turn Over

     

    Used in hospitals and DIA, includes 2 substations (Preferred and Alternate)

    Term
    Give an analagy for Demand
    Definition

    Speedometer = Kw Demand

     (speed, rate, how fast)

     

    vs

     

    Odometer = Kwh index (how much used)

    Term
    Give an analagy for watthour.
    Definition
    If a 100 watt light bulb is used for 1 hour, 100 watthours of energy is consumed.
    Term
    List the 5 demand rates
    Definition

    R-Residential (individual residence per meter)

    RD- Residential Demand (all elec homes only)(optional, more beneficial if using load controller)

    C-Commercial non-demand (under 25Kw)

    SG-Commercial Demand (if over 25Kw automatically put on SG for 1 year

    PG-Primary General (cheapest, customer owns wire, transformer, switch cabinet, etc -IE:Sewer plant)

    Term
    What is the difference between A,B & C phases? 
    Definition

    Timing.

     

    Analagy: Like a merry-go-round being pushed by 3 people. Each phase pushes current at a different time, which allows more efficiency and less effort.

     

    Power companies convert AC to DC, then back to AC to sell it to us in order to set the timing.

    Term
    When are Transformer Rated Meters required?
    Definition

    If customer uses more than a 400 amp load

    (based on breaker size which are sized to wire used)

     

    A class 320 meter can be used if at 400 amps.

    Term
    What are 2 methods of energy diversion?
    Definition
    • Tap ahead of the meter
    • Tamper with the meter
    Term
    What was the 3W 3f bank designed for?
    Definition
    Motor loads.  No longer allowed per Blue Book
    Term
    If the tickler is disconnected on a FM12, will it meter correctly?
    Definition

    Electromechanical -

    • Yes, on a Delta because it's bonded in the meter housing. 
    • No, on a Wye because registration will be lost due to the transformer configuration the phase to Neutral voltage is only 104V (similar to the misapplication of a FM2 on a Wye)

    Solid State- No, because if no N, no display

    Term
    Why must we wait for a "Meter Set Order"  on new/altered service before setting a meter?
    Definition

    To ensure the customer has:

    • Called the builder's call line
    • Received a city inspection
    Term
    List 5 considerations when applying Blue Book rules.
    Definition

     

    1.  
      1. Residential or Commercial
      2. Self-contained or Transformer Rated
      3. Overhead or Underground
      4. Single phase (2W or 3W) or 3 phase (4W)
      5. Temporary or Permanent
    Term
    Explain the difference between Residential and Commercial.
    Definition

    Residential is the metering of an individual residence. (doesn't apply if 1 meter supplies multiple apartments)

     

    Commercial is everything else, including sprinklers.

    Term
    When is a temporary unmetered service allowed?
    Definition

    Not allowed on new service.

     

    May or may not be allowed for existing service.

    (for details, see pg 35 BB)

    Term
    Define Fault Current
    Definition

    A direct short.

     

    FC amount depends on wire size and distance from transformer.

    Term
    Why and how must the fault current be limited to 10,000 amps at the meter?
    Definition

    For safety. Above 10,000 amps, the meter becomes a projectile. Below 10,000 amps, the meter will burn.

     

    Accomplished by the use of current-limiting fuses or breakers

    Term
    When is Hot Sequencing Required?
    Definition

    On Residential Self-Contained (1f or 3f) installations with a fault current of 10,000amps or less.

     

    (no current limiting fuse. CTs always hot)

     

    CTs required if over 10,000 amp Fault Current at meter.

     

    Exception 1- pre-approved current-limiting circuit breaker used.

     

    Exception 2-  a pre-approved fusible current limiting main disconnect ahead of the common bus can be used on residential meter banks.

    Term
    What options does the customer have if the fault current exceeds 10,000 amps at the meter for hot sequence metering?
    Definition

    CTs shall be used (BB pg 53)

     

    Exception 1- pre-approved fault current limiting circuit breakers can be used.

     

    Exception 2-  a pre-approved fusible current limiting main disconnect ahead of the common bus can be used on residential meter banks

    Term
    When is Cold Sequence metering required?
    Definition

    On all 3 phase self-contained commercial installations.

     

    On commercial self-contained meter installations with up to 320 amp service (1f or 3f)

     

    Exception 1- pre-approved fault current limiting circuit breaker (expensive, rarely used)

    Exception 2-  a pre-approved fusible current limiting main disconnect ahead of the common bus can be used on residential meter banks.

    Exception 3-one loop/lateral feeding only 1 single f meter with fault-current below 10,000 amps and service voltage less than 240v. Not 3 f.

    Term
    Define Multiple Service
    Definition

    1 loop or lateral service for multiple meters.

     

    Single Service = 1 loop or lateral per meter

    Term

    Under most conditions, how many services may be provided per building?

     

    When can more services be supplied?

    Definition

    One.

    Additional may be provided for:

    Special Conditions-

    * Emergency lighting

    * Fire pumps

    * Legally required standby stystems

    * Optional standby systems

    * Parallel power production systems

    Special Occupancies-

    * Multiple occupancy w/inadequate svc equip accessibility space

    * A single building large enough to require more

    Capacity Requirements-

    * If unable to provide service at a single delivery point

    Different Characteristics-

    * Different voltages/phases or loads w/different rate scheds

    Term

    How many terminals are on each meter?

    FM1,2,5,6,8,9,12,14,15,16

    Definition

           Socket       A-Base

    FM1-    4                4

    FM2-    4                4

    FM6-   13              15

    FM8-   13              15               

    FM9-   13              15

    FM12-   5                5

    FM14-   7                8

    FM15-   7                8

    FM16-   7                8

    Term
    List the Meter Socket Identification Requirements.
    Definition
    Meter socket shall be marked with a stamped, brass, aluminum or stainless steel tag securely attache to the exterior, non-removable portion of the meter socket or at the individual meter main disconnect.
    Term
    On Self Contained installations, what are the neutral wire requirements and why?
    Definition

    The neutral wire from the 5th or 7th terminal must be connected in the meter housing with minimum of #16 wire.

     

    Why? Because this "tickler" energizes the potential, other wise, free power/no disk rotation.

     

    Not connected in breaker box to prevent theft (cust could disconnect)

    Term
    What distance must the point of attachment be from the weatherhead?
    Definition
    Min 24 inches
    Term

    What is the minimum height for service-drop conductors or drip loops over ways subject to:

    Pedestrians?

    Driveways?

    Other land used by vehicles?

     

    Definition

    12 feet minimum

    16 feet minimum

    16 feet minimum

    Term
    What is the maximum height of the point of attachment?
    Definition

    24 feet above final grade

    (12 foot minimum)

    Term

    What is the minimum size and material for a:

     Service Mast?

    Service Riser?

    Definition

    Service Mast:

    2" GRC metal conduit

     

    Residential Riser:

    2" minimum for 200amp service

    3" minimum for 300amp service

     

    Term
    What is the maximum height of the weatherhead above the roofline?
    Definition
    4 feet
    Term
    What is the minimum lenth of conductor leaving the weatherhead?
    Definition

    24" Residential

    36" Commercial

    Term
    What size slip-sleeve shall be installed on all new underground services?
    Definition

    2.5 inch Sched 40

    or

    3 inch Sched 80

    Term
    Which knockout, if provided, may NOT be used in an underground electric meter housing?
    Definition
    Center
    Term
    What is the maximum number of cables in a standard single-phase pedestal?
    Definition

    6

    (1 feed, 1 streetlight, 4 services)

    Term

    What position must the high-leg be in:

    Meter Housing?

    Breaker Panel?

    Definition

    Meter Housing - far right (in order to properly energize potentials of certain meters ie: Electro-mechanical FM15 & FM8)

     

    Breaker Panel - center

    Term
    What is the maximum allowable service size?
    Definition

    4,000amp

     

    (otherwise will require a 2nd xfmr or feed)

    Term
    List 3 rules of a right triangle
    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

    Term
    Pythagorean’s Theorem
    Definition

     

       (c2 = a2 + b2)     or    (b2 = c2 - a2)

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