BUILDING ELECTRICAL AND SIGNAL SYSTEMS. Electricity Background

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1 BUILDING ELECTRICAL AND SIGNAL SYSTEMS Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 1 Electricity Background Electric charge was known to the ancient Greeks Magnetism was known historically via observation A link between electric and magnetic phenomena was noted in the 1820s Maxwell s equations/physics in the late 1800s The first use of electricity in buildings was also in the late 1800s (Edison and Tesla played a role) The impact of electricity was phenomenal it radically changed building design Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 2 1

2 Residential Building Transformation Pre-electric (and pre-mechanical) >> Post-electric (and post-mechanical) >> Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 3 Office Building Transformation predominantly exterior space predominantly interior space Pre-electric (daylit and naturally ventilated) Post-electric (electric lighting and HVAC) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 4 2

3 Static Electricity nimrod.phy.uc.edu Involves a charge accumulation and subsequent discharge Intermittent current flow (as in lightning or static shock) Limited building applications Nature s effort to increase entropy (disorder) faculty.clintoncc.suny.edu Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 5 Dynamic Electricity Involves a consistent flow of electric current Limited examples in natural systems (galvanic action is one) Vast potential in human-made systems Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 6 3

4 Electric Current Represents a flow of charge through an appropriate medium (a conductor) Moves at the speed of light (electricity is a form of electromagnetic radiation) DC = direct current (as with battery-driven devices, photovoltaics) AC = alternating current (as with public and private utilities) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 7 Direct Current (dc) involves a continuous and consistent flow of current through a circuit Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 8 4

5 Alternating Current (ac) involves a cyclic flow of changing current through a circuit Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 9 Circuits Series circuit the loads are an integral part of the network of conductors Parallel circuit there are multiple paths for current (flow can bypass any individual load) parallel circuits predominate in building power distribution systems Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 10 5

6 Circuits series parallel Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 11 Electrical Circuit Properties Voltage analogous to water pressure, it represents the difference in potential between points on a circuit, voltage is the driving force for current flow Volts (V) Amperage analogous to water flow rate, it represents the volume of electron flow; amperage is often used as a measure of circuit capacity Amps (A) (1 amp = 6 x electrons/sec) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 12 6

7 Electrical Circuit Properties Resistance analogous to friction, it accounts for energy lost due to electron flow through an imperfect conductor (no free lunch, entropy); electrical resistance is proportional to flow Ohms (Ω) Wattage represents the combined effect of voltage and amperage (wattage is a measure of the potential for work) Watts (W) W = (V)(A) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 13 Electrical Circuit Properties Frequency a measure of the cycling pattern in an alternating current circuit (North American frequency is 60 Hz; Europe is often 50 Hz) Hertz (Hz) Hz = cycle per second Power factor represents the phase relationship between voltage and amperage in a circuit (high is good, low is bad and low may incur penalty charges from a utility) PF (a decimal value) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 14 7

8 Power Factor resistive loads (incandescent lamps, electric heaters) non-resistive loads (fluorescent lamps, motors) e = voltage, i = current; p = power; note decrease in magnitude of power curve on the right (for the same voltage and current) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 15 Residential Voltage Standards only 120 V is available for loads hot neutral 120 volt, 2 wire, 1 phase 120 V is used for plug loads; 240 V for large appliances 120/240 volt, 3 wire, 1 phase from a physics perspective, voltage can be any value desired; from a practical perspective distribution voltage should match the operating voltage of connected appliances Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 16 8

9 Non-Residential Distribution Voltage Standards /480 volt, 4 wire, 3 phase 120/208 volt, 4 wire, 3 phase 480 V is used for large motors; 277 V for some fixed lighting and/or motors Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 17 Energy and Power power = instantaneous work (now!) kilowatts (kw) energy = work integrated over time kilowatt-hours (kwh) utilities often charge for both of these via an energy charge (for kwh) and a demand charge (for peak kw) other tariffs include time-of-day pricing, sliding scale pricing, and interruptible service pricing a tariff is a utility s rate structure Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 18 9

10 tariffs Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 19 the list goes on and on tariffs Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 20 10

11 Energy and Power Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 21 $867 for energy (kwh) $449 for power (kw) Energy and Power Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 22 11

12 Energy and Power Power Energy Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 23 Matching Energy and Power (for PV) Power Energy Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 24 12

13 Electricity and Building Design Electricity is a very high quality form of energy (it has low entropy) that has hundreds of uses (heating, cooling, computers, motors, toasters, TVs, ) Electrical safety caused the development of the first fire code (the National Electrical Code >> NFPA) Codes, standards, listings: NEC [typically enacted as a code] minimum system and equipment requirements ASHRAE 90.1 [a standard, often enacted as a code] a few electrical energy constraints UL [a listing incorporated into codes] product listings; everything must be listed Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 25 Building Electrical Systems Include service components concerned with getting electricity into a building safely and in a usable form (the local utility company and the design team make service decisions) Include distribution components concerned with getting electricity safely where it is needed within a building (the design team determines what is appropriate relative to distribution within the constraints of the NEC) Include load components the things that consume electricity (the owner and design team determine loads) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 26 13

14 the service-distribution boundary is negotiable on a project-by-project basis Electrical System Block Diagram utility PV? tf = transformer; sg = switchgear; ep = emergency power; mcc = motor control center; lp = lighting panel; pp = power panel Receptacles service distribution loads Luminaires Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 27 Building Electrical System One-Line Schematic Diagram some examples of service components follow >> Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 28 14

15 Service Location Planning an example of good spatial planning shop mechanical room plan for location and size of electrical spaces apx. 1% of floor area for main electrical room electrical room service large loads (mechanical and shop equipment) are adjacent to electrical room Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 29 Transformers purpose: to change voltage (usually to reduce V) internal step-down external, utility external, building service Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 30 15

16 Switchgear purpose: meter, control, monitor power flow Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 31 Emergency Power diesel generator at a hospital; with underground fuel tank architecturally is this acceptable? is such equipment just invisible? purpose: to provide power during an outage of the utility source Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 32 16

17 Building Electrical System One-Line Schematic Diagram some examples of distribution components follow >> Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 33 Distribution: Using Open Channels raised access floor this links to UFAD Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 34 17

18 Distribution: Using Closed Channels conduit Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 35 Distribution: Using Closed Channels cellular metal deck (used as structure and electrical channel) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 36 18

19 Distribution: Using Packaged Systems surface raceway Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 37 Building Electrical System One-Line Schematic Diagram some examples of load components follow >> Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 38 19

20 Fixed Loads (Motors) hard wired escalators, elevators, fans, pumps, chillers, cooling towers, air-handling units, fan-coil units, etc. HOBO datalogger fixed loads are essentially bolted down and are sized by the design team Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 39 Plug Loads convenience receptacles for movable stuff. you name it building lighting loads have been steadily reduced over the past 20 years, while plug loads have increased by like magnitude Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 40 20

21 Building Signal Systems (they are numerous and diverse) telephone data fire alarm energy and/or building management most larger buildings have EMS, BAS, or BMS: energy management system, building automation system, building management system different terms for similar systems smart buildings on the horizon? security sound (background, ambience, music) master clock closed circuit or cable TV. Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 41 Signal System Characteristics usually involve dedicated (sole-use) distribution lines for each system systems are often proprietary (secret stuff, not specified in detail) systems are often low voltage (allowing for fairly flexible distribution) rapid change is often necessary (demanding easy access and flexibility) key design issues: access, access, access (for maximum flexibility) performance specifications will be involved if system is proprietary architectural coordination (with, for example, fire zones) interconnectability (can device A talk to device B?) wireless security (emerging concern) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 42 21

22 Typical Signal System Schematic information flow service panel or computer devices site boundary signal systems typically involve communications and data Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 43 Typical Signal System Block Diagram sensor or interface device (smoke detector, motion detector, thermostat, photosensor, etc.) panel or computer (for making if then decisions) activated device (fire alarm, fan control, VAV box, computer display, etc.) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 44 22