Advanced Metering Tools for Building Energy Use Christopher Dent DENT Instruments 541.388.4774 ...

Advanced Metering Tools for Building Energy Use

Christopher DentDENT Instruments541.388.4774www.DENTinstruments.com

Columbia River ChapterAssociation of Energy EngineersOctober 8, 2012

http://www.dentinstruments.com/

Whom Am I?

President of DENT Instruments, Inc. Degrees in Astronomy, Physics,

Mechanical Engineering Licensed Professional Engineer in

Mechanical and Electrical Engineering Designer of DENT Products In Energy Research since 1978

www.DENTinstruments.com 2October 8, 2012

Who Is DENT Instruments?

Manufacturer of Metering and Data Logging Products

Founded in 1988 in Bend, Oregon 20 Employees Manufacturing in OR, TX, Asia & Europe Customer Base Includes Utilities, Fortune

500, Governments, Military 30% of Sales Are International

October 8, 2012 www.DENTinstruments.com 3

What Does DENT Make?

Permanent Mount Meters – PowerScout Series

Test & Measurement Meters – ELITEpro SP (ESP), SMARTloggers

Meters are found on Aircraft Carriers, Nuclear Submarines, Space Shuttle Launch Platform, Elevators in the Empire State Building, Electric Cars

In 50 States and on 7 ContinentsOctober 8, 2012 www.DENTinstruments.com 4

www.DENTinstruments.com 5

Electricity 101What’s a Volt? What’s an Amp?

Meters only measure two things:

Volts & Amps. Everything else (kWh, PF, VARs) is a mathematical construct. Think of a wire as a water hose

Volts = the water pressure, psi Amps = the water flow rate, gpm

October 8, 2012


Electricity 101What’s a Watt?

Watts are Power and is the rate of doing useful work

Watts = Instantaneous Volts X Amps Watts can be thought of as heating

1,000 Watts = 1 Kilowatt (kW)

KWHs are Energy and is the amount of useful work done

October 8, 2012


Electricity 101What’s a VA?

VA = V (true or rms) X A (true or rms) (1,000 VA = 1 kVA 1,000,000 VA = 1 MVA)

VA is not a “real” physical value, is not measured directly, and must be calculated

VA includes power factor and harmonics. VA is used to size wires and transformers

October 8, 2012


Electricity 101What’s a VAR?

VAR = Volt-Amps Reactive VARs are power (like kW) but do

no useful work VARs occur in reactive systems,

e.g., motors, transformers, capacitors VARs are “real” and can be measured

directly VARs = Bad

October 8, 2012


Electricity 101What is Power Factor (PF)?

Power Factor = Phase (time) Difference Between the Volts and Amps

Power Factor = W / VA or W/√(W² + VAR²) PF varies from -1 to +1 but is typically

~ -.9 to ~+.4 (Note: -.99 ≈ +.99!) Two kinds of Power Factor:

Displacement (Excludes Harmonics) Apparent (Includes Harmonics)

October 8, 2012


Electricity 101Power Factor Cont’d.

Low Power Factor (<.98 or so) = Bad Makes higher utility bills Causes heating in wiring, motors, switch

gear, and transformers (“K Rated”) Contributes to line losses in distribution

systems Reduces capacity of distribution systems

October 8, 2012


Electricity 101What are Harmonics?

Harmonics are “Noise” on the Electrical System

Harmonics are caused by Non-Linear Loads (Amps not proportional to Volts) that distort the smooth Sine wave

Waveform distortions caused by Harmonics predominantly occur on the current waveform, not the voltage waveform

Harmonics are calculated using Fourier Analysis

October 8, 2012

Waveforms

Sinusoidal Waveform – No Harmonics

Non-Sinusoidal Waveform – With Harmonics



Electricity 101Power Parameter Relationships

Power (right) Triangle VA2 = W2 + VAR2 dPF = W/√(W2 + VAR2) “Displacement PF”

does not include Harmonic currents aPF = W / VA (= Cosine Φ) “Apparent PF”

includes Harmonic currents

October 8, 2012


Electricity 202How Utilities Bill

In Descending Frequency: Energy: Kilowatt-hours, kWh Demand: Kilowatts, kW Power Factor or VARs Time-Of-Use: TOU kWh Interval kWh kVA or kVAh

October 8, 2012

Average Rates By State



Electricity 202How Utilities Bill: Demand, kW

Highest Average 15 Minute Draw (kW) in the Month

Demand charges typically range from 20-40% of the total monthly bill of C&I customers

Units are $/kW

October 8, 2012


Electricity 202How Utilities Bill: PF or VARs

VARs do no useful work but, VARs require larger wires, breakers,

service entrances, feeders, transformers, etc. so,

Utilities bill for it Sometimes also called “Power Factor

Penalty” charges

October 8, 2012


Electricity 202How Utilities Bill: TOU kWh

Cost of providing energy is different at different times of the day

Time-Of-Use billing takes that into account

TOU rates can be daily (mid-day v. night) or seasonal (summer v. winter)

Usually only for larger customers (except in CA)

October 8, 2012


Electricity 202How Utilities Bill: Interval kWh

Extreme version of TOU rates Price of Kilowatt-Hours used changes

every 15, 30, or 60 minutes Not real common yet (California, Int’l) Advantage: Reflects the spot price of

electricity Requires sophisticated metering (e.g.,

ELITEpro SP)

October 8, 2012


Electricity 202How Utilities Bill: kVAh

KiloVolt-Amp Hours Not very common (yet?) New electronic meters can measure Advantage is that kVAh includes

Harmonics and Power Factor as well as kWh

October 8, 2012

Electricity 303Electrical Systems

Common Voltages are: Low Voltage 110 – 480 V (measured directly)

Medium Voltage 4 kV – 24 kV (requires a PT)

High Voltage > 24 kV (requires a PT)

Common Currents are <5 to >5,000 A (Usually measured with “current transformers” or CTs)

Line Frequency is 60 Hz (cycles per second)


Electricity 303Electrical Systems

Common Electrical Services are: 1 Phase, 2 Wire (110V, Receptacle) 1 Phase, 3 Wire (110/220V Residential)

aka “Split Phase” 3 Phase, 3 Wire (208 or 480V

Commercial loads & motors) aka “Delta” 3 Phase, 4 Wire (208/120V Small Com &

480/277V Large Com & Industrial) “Wye”



Electricity 303Single Phase

1 Voltage (Typically 110V between

L1 & N)

October 8, 2012


Electricity 303 Three Phase Four Wire “Wye”

2 Voltages: Phase to Phase or Phase to Neutral, 480/277V or 208/120V, 120o Phase Shift

October 8, 2012


Electricity 404Metering: Basic Ideas

There are only two items that can be measured: Volts and Amps

Everything else is calculated by the meter!

Voltages up to 600V are usually measured directly

Voltages >600V are measured with Potential Transformers (PTs)

October 8, 2012


Electricity 404Metering

Current (Amps) can be measured directly up to ~5 Amps in some meters

More often, Current is measured using a Current Transducer or Current Transformer (CT) that turns a dangerous high current into a safe, low voltage

October 8, 2012


Electricity 404Metering: Example CTs

October 8, 2012


Electricity 404Metering

All Power Meters have inputs for both (and only) voltage and current

Power meters internally compute Watts, VARs, VA, and Power Factor

Power Meters have real-time clocks to track when power is being used

Storing the values over time gives kWh, kVARh, kVAh, and average PF

October 8, 2012


Meters & Metering

ELITEpro SP: A portable, 7 channel, interval recording, polyphase power meter

Suitable for single

phase to 3 phase 4 wire

Power & Energy measurement

October 8, 2012

ELITEpro SP Meter


PhaseChek™ Lights

Communication/Logging On Light

Indicator Lights for

Two Digital I/O Ports

ELITEpro SP


Panels for Bluetooth, WiFi, Cell communication options

ELITEpro SP


Voltage connections


Setting Up The ELITEpro SP™

Determine the voltage service type – number of phases, number of wires, voltage, current levels

Service type specifies the number of CTs and voltage connections needed

October 8, 2012



Launch ELOG (software) and create a Setup Table (Configuration File) Determine the data collection (integration)

interval Determine and Configure the meter Channels

and Recording Parameters Check that there is sufficient memory for the

recording time (Determine Length of Metering Period)

October 8, 2012



Connect the Meter to PC with USB or RF Set Logger Clock Download Setup Table

October 8, 2012



Connect CTs to Load Wires—watch orientation (Use Typical Setup Pics)

Connect ESP Voltage Leads Use PC to view readings in real-time

and verify proper connections Close comm connection with meter,

Disconnect PC cable from meter

October 8, 2012


1 Phase 2 Wire Setup Table

October 8, 2012

Connect Meter


Display Real-Time Values


Fun With Waveforms…


…And Harmonics



Retrieving Data From the ESP

Connect the PC to the Logger using USB or RF

Retrieve Data with Specify a Data File Name and

Destination Folder or use defaults

October 8, 2012

Sample Data File



Making Sense of the Data

ELOG Analysis Features Data File Trimming Graphs Summary Statistics Special Analysis Features

Export the Data for Further Analysis

October 8, 2012

Create A Graph



The Real World:Calculating Savings

First, Understand the Electric Bill Second, Measure All the Parameters In the

Bill Third, Collect Energy Data Before and After

any Energy Conservation Measure (ECM) Fourth, Use ELOG to Download and Filter

the Data Fifth, If Needed, Export the Data to Excel for

Additional Analysis

October 8, 2012

Tips & Tricks Always Verify Installation Before Leaving the

Site! Use Real-Time Values Display Do the Numbers Make Sense? Compare to External References

Digital Voltmeters (DVM) Clamp-on Ammeters (e.g., Amprobe) Clamp-on Power Meters (e.g., Fluke 41)

AutoPoll program for unattended data downloads (included with ELOG)



Safety

Rubber Gloves with Leather Outer Shell

“One Hand, One Wire” Rubber Mat Goggles Especially 480V Systems (or higher)! Try to Stuff the meter inside the

Cabinet and Close It

October 8, 2012

Permanent Metering

PowerScout 3, 18, 24, 48 Multi-Circuit Monitoring Meters are meant to be left at the site

indefinitely Usually part of a Building EMS or

Controls System Sometimes standalone


Typical Customers

Wal-Mart, Walgreens, Wendy's Large C & I Military Bases & Government Shopping Malls Multi-Tenant Commercial Buildings Apartments


PowerScout 3 Single& PS18 Multi-Circuit Monitor


Survey Tools

Non-Contact, Time-Of-Use, Status Loggers

SMARTLoggers TOU-L LightingLogger TOU-M MagLogger TOU-CT CT Logger TOU-C Contact Logger

Low-Cost, Simple, Good Accuracy


Survey Tools - SMARTloggers


TOU-L LightingLogger


That’s It!

Thank you!


Advanced Metering Tools for Building Energy Use Christopher Dent DENT Instruments 541.388.4774 ...

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Transcript of Advanced Metering Tools for Building Energy Use Christopher Dent DENT Instruments 541.388.4774 ...