Watt hour constantThe value of 1 revolution of the meter disk, Expressed in watt hours.
Register RatioThe 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.
Gear RatioThe 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."
Reduction at ShaftThe ratio between the number of teeth on the 1st gear of the register to the number of entries on the disk shaft.
Register Constant or Multiplier
Multiplier of the register, due to gearing.
Transformer FactorMultiplier of the register, due to CT’s and/or CT X PT ratios.
Industry standard to describe the meter
Amperage used with line voltage to set the speed of the disk in 1 hour’s time. (1000Rph 1f)(500Rph Poly f)
Watt-hour Constantx Transformer Factor
The average rate of consumption over a specific period of time
The inverse of the number of current circuits in series under test.
(Establishes the Kh of individual elements)
A Socket meter is an electromechanical meter in which the meter is designed to plug into a pre-existing meter socket / housing where all the line and load conductors are wired to the internal socket.
A’ Base Meter
An A base meter is an electromechanical meter where the line and load side conductors are physically connected to the bottom of the meter.
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
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
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.
Test Amps Formula
E x I x CC x TF1,000 Rph for single phase500 Rph for Polyphase
A 10,000 amp current limiting fuse disconnect ahead of the meter, located on the same wall as the meter within 2 feet of the meter.
The utilization of a fault current limiting disconnect device between the electric meter and the supply source.
HOT SEQUENCE METERING
The electric meter is connected directly to the service conductors without the use of a fault-current limiting disconnect or meter safety-switch device between the electric meter and the supply source.
(Wild or Power leg)
The phase having the higher phase voltage to ground on a 4-wire delta-connected service, where the midpoint of one phase winding is grounded.
The service mast is the conduit containing the service-entrance conductors where the point of attachment and the connection between the service drop and the service-entrance conductors is located above the roofline. The conduit extends to a point, and the weather head is located, above the roof eave. The conduit passes through the eave of the building or extends past the roofline without passing through the eave. The means of attachment is attached to the service mast.
Output pulses (KYZ) generated by the electric meter for use by the Customer.
The service riser is the conduit containing the service-entrance conductors where the point of attachment and the connection between the service drop and the service-entrance conductors is located on a pole or below the roofline of the building being served. The conduit extends to a point, and the weather head 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.
POINT OF ATTACHMENT
The point at which the service-drop conductors are attached to a building or other structure.
Current Transformer (CT)
An instrument transformer designed for the measurement or control of current.
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.
AUTHROIZED CLOSED LOOP
Authorized use of electric service that is temporarily not being metered.
Electric Metallic Tubing
Galvanized Rigid Conduit
Intermediate Metallic Conduit
ISOLATED TRANSFORMER BANK
A transformer bank which provides electrical service to a single customer.
NATIONAL ELECTRICAL CODE
A publication of the National Fire Protection Association, Inc.
NATIONAL ELECTRICAL SAFETY CODE
A publication of the Institute of Electrical and Electronic Engineers, Inc. as adopted by ANSI.
Any channel for holding bus bars, cables, or wires, which is designed for this purpose.
Metering of services used for the exclusive use of the individual customer for domestic purposes.
That part of the Company's distribution system, which connects the secondaries of the Company’s distribution transformers to the service drop or service lateral.
(c2 = a2 + b2) or (b2 = c2 - a2)
Pulse Demand Formula
Ke x intervals of hour x max pulses
= KW demand
Register Ratio Formula
10,000 x Kr
Kh x 3600 x revs
Time in seconds
E x I x CC x TF
(I = applied amps)
Maximum voltage deviation from average voltage.
Automated Meter ReadingAn automated method of reading electric registers (indexes)
CLASSIFICATION OF METERING
Commercial, Industrial and Residential
Temporary unmetered electric service.
Temporary unmetered electric service
The operating Companies of Xcel Energy
CONDUIT or DUCT
Standard tubular material used for mechanical protection of electrical systems which may be exposed, buried beneath the surface of the ground, or encased in a building structure as required.
The electrical inspector of the Public Authority.
The equipment necessary to measure the customer’s electric energy use and demand including meter socket, instrument transformers, protective device and meter.
MULTIPLE METER CENTER
A pre-assembled multiple metering unit or fabricated meter center using meter sockets where two or more customers are metered at a common location.
MEANS OF ATTACHMENT
Fittings used to attach service-drop conductors.(Screw knob, clevice, etc)
Point of Delivery
Point where the Company’s electric facilities are first connected to the electric facilities of the customer.
The furnishing of electric energy for the exclusive use of the individual customer.
The overhead service conductors from the last distribution pole or other aerial distribution support to and including the splices connecting to the service-entrance conductors at the building or other structure.
The underground service conductors between the Company secondary distribution system and/or transformer terminals and the connection to the service-entrance conductors in a terminal box or meter socket located outside the building wall. Where the meter is located in the building and no terminal box exists outside the building, the point of connection shall be considered the point of entrance of the service conductors into the building.
Calculate True Power (watts) and Apparent Power (VA) using given values
Watts= VAB * IA * Cos theta
VA= VAB * IA
Solve triangular problems using ALL trig functions with given values and prove wild leg and phase to phase voltage on a wye
Also solve using Pythagorean's Theorem
Sin, Cos, Tan
a2 + b2 = c2
Metering of service voltages above 480V nominal.
What is an Ohm?
The practical unit of electric resistance.
What is a demand register?
A mechanism that indicates maximum demand and also registers energy used
What is a cycle?
One complete set of positive and negative values of an alternating current or voltage
The average value of power or related quantity over a specified interval of time.
What is the min/max height for multiple indoor meter installations. (final grade to meter center)
2' min/6.5' max
The practical unit of electromotive force or potential difference.
How many services (points or delivery) will be provided to a building or other structure?
Additional services may be provided by the company for what condition
-Optional standby systems
-Parallel power production systems
Is the point of attachment installed and maintained by the customer.
Within _____ inches of the weatherhead shall the point of attachment be located?
What is the minimum length of service entrance conductors on residential services?
What is the minimum length of service entrance conductors on commercial services?
What vertical clearance is required over spaces and ways to subject to pedestrians?
What vertical clearance is required over driveways, parking lots, and alleys?
What vertical clearance is required over other land traversed by vehicles
What is the maximum height the point of attachment shall above final grade?
For existing services, the Company may grant permission to close a loop for up to a maximum of ____ calendar days?
What is the maximum service span for a 4/0 service drop
What is the maximum service span for a 1/0 service drop
What is the maximum overhead service voltage that can be attached directly to a building except where such building is used as a substation or transformer room.
Service conductor under hardscape shall be in conduit where the conduit extends ______beyond the hardscape edge.
What is the minimum depth of service laterals?
What are the required size and material of Slip Sleeves?
18” length 2 ½” Dia. Schedule 40 PVC
18” length 3” Dia. Schedule 80 PVC
Can the center knockout in the bottom of the socket be used for line side UG conductors entering socket.
What is the maximum length for an overhead service drop to a temporary service?
What is the maximum number of service entrance risers on a building?
U-guard risers shall not occupy more than _____% of the pole circumference.
What is the maximum number of cables in a standard single-phase pedestal, with six-position URD moles?
Should all electrical equipment be considered energized?
When electric meter employees are working on company premises other than electric meter shops, they shall ______.
Conform to the safety rules of other departments
When shall required Lineman’s class “2” higher rubber gloves be worn?
When cutting service drops at a fire or similar emergency
Is it required to wear a hard hat every time you’re outside your truck.
How many employees may work off of the same ladder?
What is the maximum amperage allowed on any metered load?
Can conduit coupling be installed above the roofline?
Can Phone loops, cable TV conductors, grounding clamps, etc. be attached to the service mast.
What is the maximum height of the point of attachment above the roofline?
Are junction boxes, LB’s, or other devices allowed with specific written approval from the Company’s local Electric Meter Department.
Must all meters shall be installed outdoors unless approved by the meter department for indoor location.
What is the minimum size and material a service mast shall be?
Must underground temporary service ground rod will be installed by customer on temporary panel OUTSIDE all utility easements?
What is the minimum depth of working space in front of metering equipment?
3 1/2 feet or
(depending on the fire rating)
What height shall outdoor multiple meter sockets, vertically aligned be mounted at to center of meter?
3’ min to 6.5’ max
What height shall indoor multiple meter sockets, vertically aligned be mounted at to center of meter?
2’ min to 6.5’ max
What height must a single meter be mounted?
(center of glass)
4' min to 6' max
Is a stamped brass address tag is required on any location of meter socket.
No. A non-removable portion only.
How and where must unit numbers on apartments must be marked?
By a permanent durable means at the meter socket and corresponding main service breaker, tenant panel board, doorway or entrance
What is the minimum dimensions on a 200 amp individual meter socket
19” high by 13” wide
What is the maximum length of #2 triplex service drop conductor to residential or commercial installations?
Is an authorized closed loop allowed on new electrical services.
Are Line and load conductors permitted in the same raceway or conduit.
When shall Service Mast braces or guyes be used?
When the WEATHERHEAD is more than 48 inches above the roofline.
Determine KW demand on an Itron Sentinal Form 9 meter based on given pulses.
Ke x intervals in hour x max pulses
See Participant guide, Recorders and Relays Pg 11
Determine how many internal pulses are on an Itron Sentinal Form 16 meter with a given KW demand
KW Demand x 1000
Ke x interval in hr
= Max Pulses
See Participant guide, Recorders and Relays Pg 11
Determine TF based on given values
CT x PT=TF
Calculate the watts on a meter with given values
3600 x disk rev x PKh
Time in seconds
Calculate (PKh) primary watt-hour constant on a meter installation with given values
PKh = TF x Kh
Calculate the value of Kh, Rr and Rg on a meter with given values.
Practice applicable formulas
Draw and label the following meters Abase and Socket
FM5, FM6, FM8, FM9
Draw a pictorial and schematic view of the transformers and
-Connect the conductors from these drawings to the secondary lines
- Label the voltages from this system at the secondary lines.
- Draw and connect all electromechanical SC Abase and Socket meters.
-Open Delta 3w 3Φ
-Wye bank 4w 3 Φ
-Three wire single-phase delta
-Four wire three-phase closed delta.
List missing figures in the Blue Book diagram SC-40, SC-60, TM-10, TM-20, TM-30, CR-10, CR-70, CR-70A, CR-130