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.

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.   

• 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.

Full Scale

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

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

• 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

• Shifts saturation plate to oppose or reinforce disk speed
• Potential Flux obsorbed by Saturation plate
• Affects FL by 10%

LG 304

Gang Board

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

LG 311

3 Phase Special Test

• 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

LG 354

3 Phase A-base

• 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

LG 313

A1D

LG 317

DR87

• 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

LG 318

LMR

• 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

1/2 FS

• Formula
• Reasons

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)

CL 200 = TF 40

CL 100 = TF 20

CL 50 = TF 10

Transformer rated = TF 1

Knopp board

Demand

Watts

Campbell

Max Pulse

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

Test mode

Display items

• Time remaining in interval
• Present KW
• Max KW

• Max pulses (AID only)

Possible Alternate mode

Display items

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

Meter will still accumulate Kwh/demand

Output pulses from the register for:

LMR for customer to monitor loads via computer

DR87 for billing purposes

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

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

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.

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

(Establishes the Kh of individual elements)

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

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

E x I x time factor = Kwhr

Stator

(Meter Element)

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)

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

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

166 2/3  X CL

    R_r

Register    Multiplier

classes     of register

    1               1

    2               2

    6               4

K_e x intervals of hour x max pulses  

                1000

= KW demand

KW demand x 1000

      K_e x intervals of hour

= Max Pulses

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

TA=E x I x CC x TF     

      1,000 Rph for 1f

      500 Rph for Poly f

 R_r  = 10,000 x K_r

                    TFxK_hxR_s   

K_h x 3600 x revs   

Time in seconds

E x I x CC x TF           

      1,000

 (I = applied amps)        

K_h x Cal Constant x revs

   .6 x ^V/₁₂₀ x ^amps/₅

(.6 = K_h  of standard)

^calculated/_observed  x 100 = accuracy %

(or Expected/Obtained)

 K_h x  intervals in hour  x  revs  

                   1000

or  K_h x .4 (cheat)

(expressed in kilowatts) 

       Demand x 1000    

CC X Applied voltage

Duration of Alt Mode

Duration of Test Mode

(ABB/Sentinel)

ABB-   

Alt mode will reset after 1 cycle

Test mode must be undone manually

Sentinel-

Both modes reset after 1 hour

15a/120V 2W

Kh 1.8

Rr 55 5/9

30a/240V 3Wdelta

Kh 7.2

Rr 13 8/9

30a/120V 3W

Kh 14.4

Rr 6 17/18

30a/120V 4WY

Kh 21.6

Rr 9 7/27

4 Main Formulas

(Shop Staples)

TA

Watts

Demand

FS

Feel flux with magnet

Continuity test with fluke

Continuity test with Continuity Tester

Meter disk vibration

30a/240V 4Wdelta

Kh 28.8

Rr 6 17/18

2.5a/120V 3W

Kh 1.2

Rr 166 2/3

2.5a/120V 4WY

Kh 1.8

Rr 111 1/9

What are the following expressed in?

Kh

Ke pulse value

KYZ pulse value

P/R

Demand

Kh = watthours

Ke = watts

KYZ = watts

P/R = watts

Demand = KW

Accuracy Limits PUC vs Xcel

FL & LL

PF

Demand

             PUC / XCEL 

FL & LL     +/- 2%   /   +/- .5%

PF           +/- 2%   /   +/- .6%

Demand +/- 1% of FS

Sentinal Meterprogrammed with wrong Kh.

Which will be correct?

Customer Bill?

Tests?

Timing?

Ke/KYZ pulse value?

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.

ABB Meter programmed with wrong Kh.

Which will be correct?

Customer Bill?

Tests?

Timing?

Ke/KYZ pulse value?

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.

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?

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.

Expain the difference between internal and external pulses.

(imput vs output)

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)

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

Base

Meter Disk

Cover

Stator

Permanent Magnet

Kilowatthour Register

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

•  
  • 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.

What EM meters set on a

3W 3f   (L or  D)

(no longer allowed per book)

Triplex  -  FM 12 (self contained)

3W 3f loop - FM 5 (transformer rated)

3W 3f   D  or L

What EM meters set on a

4W 3f   L  or D

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

What EM meters set on a

Wye System

Duplex - FM1

Triplex - FM12

Quad loop - FM14, FM16,  TR- FM6, FM9

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

FM1,

FM12 & FM5 (single phase) 

All, depending on potential rating.

120v - 1fD

240v - 3W 3f D or Wye

480v - 480 3W 3f D or Wye

(Closed or open Delta)

1f D or L

4W 3f   D or L

LG #421

Set a FM2 Socket Meter

• 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

The higher voltage of a transformer

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

or

instrument transformer.

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!

Ground = connected to Earth

Neutral = returns to the source (transformer)

• Open loop (2,3 or 4 wire)
• Spun Secondary (duplex, triplex, etc)
• Midspan Loop

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

• 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)

Automatic Turn Over

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

Speedometer = Kw Demand

 (speed, rate, how fast)

vs

Odometer = Kwh index (how much used)

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)

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.

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.

• Tap ahead of the meter
• Tamper with the meter

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

To ensure the customer has:

• Called the builder's call line
• Received a city inspection

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

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

Commercial is everything else, including sprinklers.

Not allowed on new service.

May or may not be allowed for existing service.

(for details, see pg 35 BB)

A direct short.

FC amount depends on wire size and distance from transformer.

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

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.

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

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.

1 loop or lateral service for multiple meters.

Single Service = 1 loop or lateral per meter

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

When can more services be supplied?

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

How many terminals are on each meter?

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

       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

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)

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

Pedestrians?

Driveways?

Other land used by vehicles?

12 feet minimum

16 feet minimum

16 feet minimum

24 feet above final grade

(12 foot minimum)

What is the minimum size and material for a:

 Service Mast?

Service Riser?

Service Mast:

2" GRC metal conduit

Residential Riser:

2" minimum for 200amp service

3" minimum for 300amp service

24" Residential

36" Commercial

2.5 inch Sched 40

or

3 inch Sched 80

6

(1 feed, 1 streetlight, 4 services)

What position must the high-leg be in:

Meter Housing?

Breaker Panel?

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

Breaker Panel - center

4,000amp

(otherwise will require a 2nd xfmr or feed)

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

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