AMCA International Air System Motor, Drives – Sizing and Selection Trinity Persful VP Marketing, Twin City Fan, Minneapolis, MN tpersful@tcf.com Air System Engineering & Technology (ASET) Conference–US San Antonio, TX • Hyatt Regency San Antonio Riverwalk • March 6 - 7, 2018 Copyright AMCA International • www.amca.org Professional Development Hours (PDH) Certificates The Air Movement and Control Association International (AMCA), has met the standards and requirements of the Registered Continuing Education Providers Program. Credit earned on completion of this program will be reported to the RCEP. A certificate of completion will be issued to each participant. As such, it does not include content that may be deemed or construed to be an approval or endorsement by NCEES or RCEP. 2 Copyright Materials This educational activity is protected by U.S. and International copyright laws. Reproduction, distribution, display, and use of the educational activity without written permission of the presenter is prohibited. © AMCA International 3 4 Learning Objectives ο§ Understand the role of fans in energy efficiency ο§ Understand reference fan calculations using AMCA 207/208 ο§ Become familiar with part load energy calculations using AMCA 207/208 Structure 1. Brief review of Fan Efficiency Index (FEI) • FEI = FEPref/FEPact 2. Reference Fan Electrical Input Power (FEPref) • Based off of flow and pressure of operating point = max power allowed • Calculated transmission loss • Calculated motor loss 3. Actual Fan Electrical Input Power (FEPact) • Wire to air tests or • Fan power + calculations for belt losses, coupling, vfd losses, control losses, motor losses March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 5 AMCA 207 Standard AMCA 207 – Fan System Efficiency and Fan System Input Power Calculation • Provides a method to estimate the input power and efficiency of a fan SYSTEM • Models commonly used components • Scope – fans covered by AMCA 210/211, AMCA 230 (circulating fans), AMCA 260 (induced flow) AMCA 208 Standard AMCA 208 – Calculation of the Fan Energy Index (FEI) • Defines the FEI • Allows a comparison basis to compare fan energy performance • Regulatory bodies can use to define the requirements What’s a Fan? + + Intro to FEI In the most simple terms, we compare a fan selection to a reference(default) fan. How well does the selection compare? πΉπΉπΉπΉπΉπΉππππππ,ππ π π π π π π π π π π π π π π π π π π πΉπΉπΉπΉπΉπΉ πΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈ πΌπΌπΌπΌπΌπΌπΌπΌπΌπΌ ππππππππππ = πΉπΉπΉπΉπΉπΉ = πΉπΉπΉπΉπΉπΉππππππ,ππ π΄π΄π΄π΄π΄π΄π΄π΄π΄π΄π΄π΄ πΉπΉπΉπΉπΉπΉ πΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈπΈ πΌπΌπΌπΌπΌπΌπΌπΌπΌπΌ ππππππππππ FEI = Fan Efficiency Index Fan Power Electrical Power In Aero Loss (10%20%) π―π―ππ,ππππππ Wire to Air Power Drive Loss (10%) πΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌ, ππππππ Motor Loss (10%) πΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌ, ππππππ Fan Power Out Reference Fan Electrical Input Power (FEPref) πΉπΉπΉπΉπΉπΉππππππ,ππ = 1 1 π»π»ππ,ππππππ ( )( ) πππ‘π‘π‘π‘π‘π‘π‘π‘π‘π‘,ππππππ ππππππππππππ,ππππππ x .7457 π»π»ππ = Fan shaft power (kW, hp) η= efficiency The reference fan is defined as one that requires a reference fan shaft power, uses a V-belt drive, has a motor based on IE3 for 4 pole, 60Hz with no speed control. Reference Fan Electrical Input Power (FEPref) 1 1 )( ) πππ‘π‘π‘π‘π‘π‘π‘π‘π‘π‘,ππππππ ππππππππππππ,ππππππ πΉπΉπΉπΉπΉπΉππππππ,ππ = π―π―ππ,ππππππ ( Qi - selected fan airflow π―π―π’π’,ππππππ = x .7457 (ππππ + Q0 )(ππ + ππ0 × 6,343 × ππππ Pi - selected fan total pressure (ducted), or static pressure (nonducted) Ρ - air density ρstd - standard air density Q0 - 0.118 m3/s (SI), or 250 cfm (IP) P0 - 100 Pa (SI), or 0.40 in.wg (IP) η0 - 66% for ducted applications and 60% for nonducted applications ρ ρπ π π π π π ) Reference Fan Electrical Input Power (FEPref) πΉπΉπΉπΉπΉπΉππππππ,ππ = ππ 1 π―π―ππ,ππππππ ( )( ) πΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌ,ππππππ ππππππππππππ,ππππππ x .7457 The reference fan transmission efficiency is calculated using the same equations as found in ANSI/AMCA Standard 207 for V-belt drives. The efficiency of a V-belt transmission is calculated as: 13 Reference Fan Electrical Input Power (FEPref) Transmission efficiency = V-belt power transmission 0.96 0.94 Efficiency 0.92 0.9 0.88 0.86 0.84 0 5 10 15 20 25 Hi,ref (HP) Efficiency March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 14 Reference Fan Electrical Input Power (FEPref) πΉπΉπΉπΉπΉπΉππππππ,ππ = ππ 1 π―π―ππ,ππππππ ( )( ) πΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌ,ππππππ ππππππππππππ,ππππππ x .7457 • The reference fan = a motor efficiency based on the IE3, 4 pole 60 Hz motor. • To simplify the calculation - a curve fit is used through the IE3 motor efficiency requirements. • The result is a reference motor efficiency that varies continuously based on the required motor output power. March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 15 Reference Fan Electrical Input Power (FEPref) πΉπΉπΉπΉπΉπΉππππππ,ππ = ππ ππ π―π―ππ,ππππππ ( )( ) πΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌ,ππππππ πΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌ,ππππππ x .7457 ηmtr,ref 0.95 0.9 Efficiency πΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌπΌ, ππππππ= 0.85 -.0038*[log10(π»π»π‘π‘,ππππππ x.7457)]40.8 3 .0258*[log10(π»π»π‘π‘,ππππππ x.7457)] -.725 *[log10(π»π»π‘π‘,ππππππ x.7457)]2+ 0.75 .1255*[log10(π»π»π‘π‘,ππππππ x.7457)]+.8503 ηmtr,ref 0.7 0 2 4 6 HP 8 10 12 Fan Configuration Motor Type FEPact Determination Example Applications Fan for which the motor is not yet selected N/A Default motor efficiency calculation • • Fan with motor Any Wire to air measurements (211) • Motors for which no test standards apply Polyphase induction motors within the scope of AMCA 207 AMCA 207 Calculations • 3 phase regulated motors 3 phase non-regulated (AO, XP, 2 speed, etc.) Motors for which performance can be measured in accordance with a known standard Motor tests • • • • Fan with motor and speed control Fans sold without motors Catalogs used for fans prior to motor selection Single phase regulated motors Single phase nonregulated 3 phase fractional motors Motors where AMCA 207 does not apply Default motor efficiencies Any Wire to air measurements (211) • Motors for which no test standards apply Polyphase induction motors, reg/nonreg within AMCA207 AMCA 207 Calculations • 3 phase regulated motors 3 phase non-regulated (AO, XP, 2 speed, etc.) • Actual Fan Electrical Input Power (FEPact) Now that the reference fan is defined, let’s define the actual power consumption – FEPact. FEPact = Shaft to air + transmission loss + coupling loss + motor loss + VFD loss March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 19 Actual Fan Electrical Input Power (FEPact) V-belt power transmission • The efficiency of a V-belt transmission is calculated as: 0.96 Efficiency 0.94 0.92 0.9 0.88 0.86 0.84 0 5 10 15 20 25 Hi,ref Efficiency March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 20 Actual Fan Electrical Input Power (FEPact) Synchronous belt power transmission • The efficiency of a synchronous belt transmission is calculated as: March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 21 Actual Fan Electrical Input Power (FEPact) Flexible coupling power transmission • The efficiency of a flexible shaft coupling is: No power transmission • If the motor shaft is rigidly connected to the fan impeller, the March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 22 Actual Fan Electrical Input Power (FEPact) The motor and VFD efficiencies are combined into a single value. Steps to determine motor/vfd combined efficiency: 1. Determine the motor output power (Hm) 2. Calculate motor load ratio (Lm) 3. Determine the motor efficiency (ηm) 4. Determine the control (VFD) load ratio (Lc) 5. Determine the motor and VFD efficiency (ηmc) 6. Determine the motor input power (Wc) March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 23 Actual Fan Electrical Input Power (FEPact) The motor and VFD efficiencies are combined into a single value. Steps to determine motor/vfd combined efficiency: 1. Determine motor output power π»π»ππ π»π»ππ = ηπ΅π΅ where Hi is the fan input power and ηπ΅π΅ is the transmission efficiency calculated from earlier. March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 24 Actual Fan Electrical Input Power (FEPact) The motor and VFD efficiencies are combined into a single value. Steps to determine motor/vfd combined efficiency: 1. Determine motor output power 2. Determine the motor load ratio Hm = motor output power Hmo =nameplate output power March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 25 Actual Fan Electrical Input Power (FEPact) The motor and VFD efficiencies are combined into a single value. Steps to determine motor/vfd combined efficiency: 1. Determine the motor output power 2. Calculate motor load ratio 3. Determine the motor efficiency ηm is the Nominal motor efficiency ηR is the Nominal regulated efficiency Lm is the motor load ratio March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 26 March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 27 March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 28 Actual Fan Electrical Input Power (FEPact) The motor and VFD efficiencies are combined into a single value. Steps to determine motor/vfd combined efficiency: 1. Determine the motor output power 2. Calculate motor load ratio 3. Determine the motor efficiency 4. Determine the control (VFD) load ratio March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 29 Actual Fan Electrical Input Power (FEPact) The motor and VFD efficiencies are combined into a single value. Steps to determine motor/vfd combined efficiency: 1. Determine the motor output power 2. Calculate motor load ratio 3. Determine the motor efficiency 4. Determine the control (VFD) load ratio 5. Determine the motor and VFD efficiency March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 30 March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 31 System integration - (FEPact) The fan system input power in kW for combined motor and VFD operation is calculated by: 1. Determine the motor output power 2. Calculate motor load ratio 3. Determine the motor efficiency ππππ = Where: 4. Determine the control (VFD) load ratio 5. Determine the motor and VFD .746π»π»ππ ηππππ ηπ΅π΅ ηππππ = Combined motor and VFD efficiency efficiency ηοΏ½π΅π΅ = transmission efficiency 6. Determine the motor input power March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 32 System integration - (FEPact) Overall fan system power input and efficiency are determined by combining results for the fan system components. The fan system input power in kW for DOL motor operation is calculated by: ππππ = .746π»π»ππ ηππ ηπ΅π΅ Where: ηππ = motor efficiency ηοΏ½π΅π΅ = transmission efficiency March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 33 FEI Range for Centrifugal with Speed Control EFFICIENT FAN INEFFICIENT FAN FEI Range for Adjustable Pitch Axial Worked example for a housed centrifugal fan with belt transmission operating DOL A housed centrifugal fan is selected to deliver 5.94 m3/s (12,000 cfm) at a fan total pressure of 1250 Pa (5 in. wg). The input power to the fan, Hi, is 15.8 kW (11.8 hp) and fan speed is 1500 rpm. The fan is driven through a V-belt transmission with a 15 hp, four-pole ODP premium efficiency motor regulated under EISA 2007. March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 36 Worked example for a housed centrifugal fan with belt transmission operating DOL 1. Calculate the transmission efficiency March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 37 Worked example for a housed centrifugal fan with belt transmission operating DOL 2. Calculate the motor output power March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 38 Worked example for a housed centrifugal fan with belt transmission operating DOL 3. Calculate the motor load ratio March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 39 Worked example for a housed centrifugal fan with belt transmission operating DOL 4. Calculate the motor efficiency, ηm. Obtain the motor nominal efficiency, ηR, from Table A1 and the motor performance constants, a and b, from Table D1. The constant c is calculated from a and b. March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 40 Worked example for a housed centrifugal fan with belt transmission operating DOL 4. Calculate the motor/VFD efficiency. Obtain the VFD constants d, e, and f from Table C1. March 6-7, 2018 AMCA ASET-US Conference, San Antonio, TX 41 Status • AMCA Standard 208 is published • AMCA 208 is integrated into ISO 12759 • Default losses for drive components based on AMCA 207 • FEI would be calculated using rating data taken during AMCA 210 or ISO 5801 tests • U.S. DOE regulation stalled, but would be based on FEI • California stated regulation picking up where DOE left off • ASHRAE 90.1 replacing FEG with FEI • U.S. efficiency rebates will be based on FEI ©2016 Air Movement and Control Association. All Rights Reserved. 42 Resources • AMCA International: www.amca.org • AMCA Standards Bookstore: www.amca.org/store ©2016 Air Movement and Control Association. All Rights Reserved. 43 Questions? Trinity Persful VP Marketing Twin City Fan Company tpersful@tcf.com 44
