ELECTRICAL Seminar. B A L A Consulting Engineers, Inc. Edward J. Lynch, PE Vice President, Electrical Department Manager.

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1 B A L A Consulting Engineers, Inc. PECO Line 13.2kV Incoming Service No. 1 Utility/Generator Medium Voltage Switchgear PECO Line 13.2kV Incoming Service No. 2 Unit Substation ELECTRICAL Seminar HVAC Equip. HVAC Equip. Edward J. Lynch, PE Vice President, Electrical Department Manager UPS System Control Cabinet December 19, 2005 QUALITY PROJECTS AND QUALITY RELATIONSHIPS

2 LIGHTING Kelvin Temperature K (orange-red) 9000K (blue) - Typical Light Source Ranges K to 3100K Warm K to 3600K Mid-Range K to 6300K Cool Color Rendering Index - Scale 0 to CRI of 100 indicates no color shift from reference source - Lower CRI indicates more pronounced color shift

3 LIGHT SOURCES/LAMPS Incandescent Fluorescent Mercury Vapor Metal Halide High Pressure Sodium -15 to 18 Lumens/Watt 2750K to 3700K CRI to 90 Lumens/Watt 2700 K to 6300K CRI 48 to Lumens/Watt 3300Kto 5900K CRI 22 to Lumens/Watt 3100K to 4200K CRI 65 to Lumens/Watt 2100K CRI 20 to 22

4 LIGHTING LEVELS One Lumen/Square Foot = One Foot candle Illuminate Engineering Society of North America (IES) Recommended Illumination Levels Zonal Cavity Method 1. Determine Cavity Ratio 2. Determine Reflections 3. Select Coefficient of Utilization 4. Compute Average Illumination Level # Fixtures = Foot candles X AREA Lamps/Fixtures x Lumens/Lamps x CU x LLF LLF = Light Loss Factor

5 LIGHTING CONTROLS Occupancy Sensors Daylight Sensors Dimmers Time Program

6 ELECTRICAL Basic Factors V = Voltage (Volts) I = Current ( Amps) R = Resistance (OHMS) V = I X R Series Resistances R Total = R1 + R2 Parallel Resistances R Total = R1 X R2 R1 + R2

7 ELECTRICAL Direct Current P = V x I Alternating Current Single Phase P = V x I x PF Where PF = Power Factor Three Phase P = V x I x 3 x PF Power Factor = Watts Volt - Amperes Distribution Equipment Switchgear/Switchboards Bus Ducts Panelboards Transformers

8 ELECTRICAL Utilization Equipment Lighting Fixtures Heaters Motors Office Equipment Common Voltage 240/120 Volt Single Phase 208Y/120 Volt Three Phase 480Y/277 Volt Three Phase Over Current Protection Circuit Breakers Fuses

9 ELECTRICAL Wiring Methods Conduit Loads Lighting Mech. Systems Elevators Power Quality Transients Brownouts Emergency Power Battery Units Cable Process Equip. Office Equip. Blackouts Harmonics Engine Generators

10 ELECTRICAL UTILITY SERVICE Primary Medium Voltage kV or 34kV - Large Building / Load Secondary Low Voltage - 480Y / 277V or 208Y / 120V - Small Building / Load Revenue Metering - Consumption kw/hr. - Demand - kw

11 EMERGENCY/STANDBY GENERATORS Fuel Source - Diesel or Natural Gas Emergency Systems -Life Safety Legally Required Standby Systems - Heating & Refrigeration Systems - Ventilation & Smoke Removal Systems -Elevators Optional Standby Systems - Selected Loads

12 POWER QUALITY Grounding Surge Protection Voltage Regulation Harmonics Lightning Protection Uninterruptible Power Supply (UPS)

13 MAIN POWER DISTRIBUTION PECO Line 13.2kV Incoming Service No. 1 Utility/Generator Medium Voltage Switchgear PECO Line 13.2kV Incoming Service No. 2 Unit Substation HVAC Equip. HVAC Equip. UPS System Control Cabinet

14 UPS POWER DISTRIBUTION UPS Output Distribution Switchboard UPS Distribution Panel -1A UPS Distribution Panel -2A PDU 1A PDU 2A PDU 3A PDU 4A PDU 5A UPS Distribution Panel -1B UPS Distribution Panel -2B PDU 1B PDU 2B PDU 3B PDU 4B PDU 5B

15 CODES National Electrical Code NFPA70 National Fire Alarm Code NFPA72 Life Safety Code NFPA101 Healthcare Facilities NFPA99 International Building Code IBC American with Disabilities Act ADA

16 FIRE ALARMS Codes NFPA BOCA Manual Pull Stations Automatic Detectors Ionization Photoelectric Indicating Devices Horns/Speaker Voice Evacuation ADA Thermal Strobes

17 FIRE ALARM Fireman s Phone Wiring Methods Electrical Supervision

18 Questions Answers

19 B A L A Consulting Engineers, Inc. HVAC SEMINAR Thomas M. Harrigan, PE Mechanical Dept. Manager December 12, 2005 QUALITY PROJECTS AND QUALITY RELATIONSHIPS

20 WHAT WE WOULD LIKE TO COVER HVAC Overview Typical Systems Q & A

21 GLOSSARY BTU - Energy to heat 1 lb. water/1º F. Ton - Amount of heat released (cooling effect) of 1 ton of ice melting in one day 144 x 2000 = 12,000 BTU/hr. 24 Evaporator - A coil or heat exchanger that removes heat from an airstream or fluid. Condenser - A coil or heat exchanger that releases heat to an airstream or fluid. CFM - (Cubic Feet per Minute) Measure of air quantity. Direct Expansion - A system that uses the refrigerant to directly cool the airstream through the evaporator. Economizer - The ability to cool without using refrigeration.

22 TYPES OF HVAC SYSTEMS Direct Expansion (DX Unit) - Rooftop VAV - Water Source Heat Pump - Water Cooled VAV Central Station Chilled Water

23 BASIC BUILDING BLOCK DX SPLIT SYSTEM UNIT Roof Thermal Expansion Valve 115º F Liquid Line 285 psi 55º /54º Fan 95º F Condenser Hot Gas Line SA= Supply Air RA= Return Air 140º F 285 psi 80º /67º 40º F RA DX Cooling Coil 70 psi Suction Line Compressor SA

24 ROOFTOP VAV Rooftop VAV- A roof mounted packaged air conditioning that includes all the components for a complete cooling system.

25 ROOFTOP VAV DX Rooftop Unit Outside Air SA= Supply Air RA= Return Air RA SA SA RA SA SA

26 ROOFTOP VAV Pros Cons - Equipment does not consume floor space - Single Package - Single Responsibility - Available in Sizes from tons - Each AC-system is independent of the other - no domino effect - Units on Roof - architect, structural maintenance issue - Not suited to buildings 5 or more stories (shaft space required) - Usually only as efficient as codes require

27 WATER SOURCE HEAT PUMP A single package that provides cooling and heating Units are distributed around the floor plan connected by a condenser water loop to reject heat to atmosphere. Heating Cycle Cooling Cycle Rejected Heat Heated Air Cooled Air Condenser/Evaporator Condenser/Evaporator Water Loop Water Loop

28 Cooling Tower WATER SOURCE HEAT PUMP SA= Supply Air RA= Return Air Water Heater Boiler (Heat Source) RA RA SA SA RA RA SA SA

29 WATER SOURCE HEAT PUMP Allows for Reverse Cycle (heat pump) Heating - Occupied & Unoccupied Pros Cons - Distributed units around floor plan - limits cooling or heating failure to small area. - Reduced ductwork requirements - Good energy costs - Equipment in occupied space - sound, service issues - Water piping above occupied space - Limited outside air capabilities - localized humidity issues if outside air is not treated - Needs significant interior space to be effective (heat pump heating)

30 WATER COOLED VAV Individual fusing and single power connection Acoustically treated discharge plenum A self contained air conditioning unit with variable air volume fan & refrigeration. The unit rejects heat to a water loop. MicroTech control panel Quiet, efficient multiple compressor design

31 WATER COOLED VAV Outside Air Outside Air SA= Supply Air DX AC RA SA SA RA= Return Air DX AC RA SA SA Heat Exchanger Cooling Tower Mechanical Room

32 WATER COOLED VAV Pros Cons - One unit per floor - often used on high rise buildings - VAV Capability - Compact Installation - Available with water side economizer if shaft space for outside air economizer is limited - Can be more efficient (tower selection) - Unit requires occupied floor space (core) - Sound issues with unit location - Duct height constraints leaving mechanical room - Limited outside air economizer capability

33 CENTRAL STATION CHILLED WATER Chilled water distributed at 44º F, is piped to air handlers around the building.

34 CENTRAL STATION CHILLED WATER RA SA SA SA= Supply Air RA= Return Air RA SA SA Cooling Tower OA Intake Areaway Relief Discharge Chilled Water AHU Water Cooled Chiller

35 CENTRAL STATION CHILLED WATER Pros - Centralized location for cooling/heating equipment - Best efficiency of components - Superior Control (compared to DX) - Most opportunities for alternate energy sources, dual fuels, heat reclaim Cons - Expense - Space

36 TERMINAL UNITS VAV Shut Off Box - Used as shown for truly interior spaces - Used with a reheat coil where there is a roof heating load

37 TERMINAL UNITS Fan Powered VAV - used on the perimeter where higher heating air flows are required - or in conference rooms where air changes are desired. Series Parallel

38 DESIGN ISSUES - HEIGHT INTERFERENCE Finished Floor Slab 6 Steel Fire Proofing 1-2 Available for Duct Height 7-12 Clearance for Lights, Sprinklers, Diffusers Floor to Floor Ceiling Height 9-10 Finished Floor

39 Questions Answers