BUILDING TECHNOLOGIE

May 14, 2014

ASRAC Pumps Working Group Webinar Meeting

Metric: From Test Stand to PER
2

Overview

To Discuss Today:• Metric nomenclature

• Examples for different pump configurations

– Motor and driver part load loss factor

– Testing vs calculation options

• Revised calculator & How‐To slides

• Impact of test procedure and metric on standard

To Discuss at Next RegNeg Meeting (May 28th and 29th):

• Comparison of MEI and PER

• Comments on material presented on May 14th webinar

• Implementation of PERCL and PERVL
3

Metric Applicability to Pump Configurations

Pump Configuration

Bare Pump* Bare Pump + Motor Bare Pump + 

Metric CoverageBare Pump PERCL Does not include motor efficiency Does not d

losses 

Bare Pump + Driver PERCL (w/ std. driver) PERCL Does not d

losses 

Bare Pump + Driver +

Controls

PERCL

(w/ std. driver

and controls)

PERCL

(w/ std. controls) P

Pump Motor

Pump Control M

• Define a unique, but similar, metric for controlled versus uncont

pumps

• Uncontrolled pumps ‐> Constant Load Pump Energy Rating 

• Controlled pumps ‐> Variable Load Pump Energy Rating (PE

*Pumps sold with non‐electric drives could be rated as

bare pumps
4

Pump Energy Rating (PER) and Index (PEI) NomPump Energy Rating (PER) CL and VL: equally weighted average elec

power to the ‘pump’ measured (or calculated) at the driver input or, 

controls input, over a specified load profile:

Where:

• wi = weight at each load point i

• Pini = power input to the “pump” at the driver, inclusive of the 

present, (hp)

• i = Percentage of flow at the best efficiency point (BEP) of the 

• i = 110%, 100%, 75% of Best Efficiency Point (BEP) flow at 

for uncontrolled pumps

• i = 25%, 50%, 75%, and 100% of BEP flow at nominal spee

sold with motors and controls

Pump Energy Index (PEI) CL and VL: PER CL and VL, for a given pump 

the PERCL for a minimally compliant pump (PERmax):

௜௡௜ܲ ௜߱෍ ൌ ࡸࢂ/ࡸ࡯ࡾࡱࡼ

௜

ൌ ࡸࢂ/ࡸ࡯ࡵࡱࡼ

௅௏/௅஼ܴܧܲ

௫௠௔ܴܧܲ
5

Determining PEICL for an Uncontrolled Pump

• Pump Performance

– Pi values are the tested shaft input power to the pump (speed x torque) at ea

• i = 75%, 100%, and 110% of flow rate at BEP of the pump

• Equal weighting

• Motor Performance (Losses)

– Lrated is the full load losses of a motor that is paired with the pump for pumps 

– Lrated is the full load losses of an enclosed motor that is minimally compliant 

regulations (10 CFR 431.25) for general purpose motors (subtype I) for all pu

and general purpose motors (subtype II) for ESCC pumps

ܲܫܧ ௅஼ൌ ఠబ.ళఱ ௉೔೙బ.ళఱ ାఠಳಶು ௉೔೙ಳಶು ାఠభ.భ ௉೔೙భ.భ ௉ாோ೘ೌೣ

ൌ

߱଴.଻ହ ܲ௜௡଴.଻ହ ൅ ߱஻ா௉ ܲ௜௡஻ா௉ ൅ ߱ଵ.ଵ ܲ௜௡ଵ.ଵ

߱଴.଻ହ

ܲு௬ௗ௥௢,଴.଻ହ

0.95 ∗ ߟ௣௨௠௣ ൅ ܮ଴.଻ହ ൅ ߱஻ா௉

ܲு௬ௗ௥௢,஻ா௉

ߟ௣௨௠௣ ൅ ܮ஻ா௉ ൅ ߱ଵ.ଵ

ܲு௬ௗ௥௢

0.985 ∗ ߟ

=

భయ

∗ ௉బ.ళఱା௅బ.ళఱ ାభయ∗ ௉ಳಶುା௅ಳಶು ାభయ∗ ௉భ.భା௅భ.భ

భయ

∗

ುಹ೤೏ೝ೚,బ.ళఱ

బ.వఱ∗ആ೛ೠ೘೛ା௅బ.ళఱ ାభయ∗ ುಹ೤೏ೝ೚,ಳಶು ആ೛ೠ೘೛ ା௅ಳಶು ାభయ∗ ುಹ೤೏ೝ೚,భ.భ బ.వఴఱ∗ആ೛ೠ೘೛ା௅భ.భ

• No Controls Performance
6

Determining PEIVL for a Controlled Pump

ൌ௏௅ ܫܧܲ

1

η௖௧௥௟

߱଴.ଶହ ܲ௜௡଴.ଶହ ൅ ߱଴.ହ଴ ܲ௜௡଴.ହ଴ ൅ ߱଴.଻ହ ܲ௜௡଴.଻ହ ൅ ߱஻ா௉ ܲ

߱଴.଻ହ

ܲு௬ௗ௥௢,଴.଻ହ

0.95 ∗ ߟ௣௨௠௣ ൅ ܮ଴.଻ହ ൅ ߱஻ா௉

ܲு௬ௗ௥௢,஻ா௉

ߟ௣௨௠௣ ൅ ܮ஻ா௉ ൅ ߱ଵ.ଵ

ܲ

0.9

=

ଵ

஗೎೟ೝ೗

భర

௉೔೙బ.మఱ ାభర ௉೔೙బ.ఱబ ାభర ௉೔೙బ.ళఱ ାభర ௉೔೙ಳಶು

ఠబ.ళఱ

ುಹ೤೏ೝ೚,బ.ళఱ

బ.వఱ∗ആ೛ೠ೘೛ା௅బ.ళఱ ାఠಳಶು

ುಹ೤೏ೝ೚,ಳಶು

ആ೛ೠ೘೛

ା௅ಳಶು ାఠభ.భ

ುಹ೤೏ೝ೚,భ.భ

బ.వఴఱ∗ആ೛ೠ೘೛

• Pump Performance

– Pi values are the tested shaft input power to the pump (speed x torque) at ea

• i = 25%, 50%, 75%, and 100% of flow rate at BEP of the pump

• Equal weighting

• Motor Performance (Losses)

– Lrated is the full load losses of a motor that is paired with the pump for pumps 

• Controls Performance

– Benefit is captured in calculation of bare shaft input power

– Could still account for drive efficiency
7

Minimally Compliant Pump

• PER for a minimally compliant pump

– Based on PER Standard set through Standards analysis

– Assumes a pump curve shape for the minimally compliant pump and always 

controls

– Motor losses are that of a minimally compliant enclosed motor for the appr

– The minimally compliant pump efficiency is calculated for each pump type b

of flow and speed

ܲܧܴ௔௠௫ ൌ ߱଴.଻ହ

ܲு௬ௗ௥௢,଴.଻ହ

0.95 ∗ ߟ௣௨௠௣,௠௜௡ ൅ ܮ଴.଻ହ ൅ ߱஻ா௉

ܲு௬ௗ௥௢,஻ா௉

௣௠௨௣ߟ

൅ ܮ஻ா௉ ൅ ߱ଵ.ଵ

ܲு

0.985 

ߟ௣௨௠௣ ൌ 88.59 ∗ ln ܰݏ ൅ 13.46 ∗ ln ܳ௠௘௧௥௜௖ െ 11.48 ∗ ln ܰݏ ଶ െ 0.85 ∗ ln ܳ 

∗ ln ܳ െܥ

• Where:

– Ns is the specific speed of the pump in metric units,

– Q is the flow rate of the pump at BEP in m3/hr,

– C is the C‐value of the surface, which is set based on the speed of rotation o

– All values are for the pump at 50 Hz
8

Pump Used for Example CalculationsNote that this example is for a pump and motor combination. If th

group decides to include engine‐driven pumps in the scope of this

rulemaking, similar calculation methods will have to be developed 

separate physical test applied.

Pump Motor (if applicable) 

Type: OH1Rated conditions:• Rated Flow: 900 GPM

• Rated Head: 160 ft

• Rated Speed: 1750 RPM

Power: 60 hpEfficiency: 95%No load speed (TestMotor): 1780 RPM [fourpole motor]
9

BEP Flow Rate Determination

– In accordance with HI 40.6, sweep through at least seven flow 

from shutoff to maximum flow rate

• HI 40.6 requires points of approximately 40, 60, 75, 90, 100, 110

of the flow rate at the expected BEP of the pump (if the actual B

flow is displaced by more than 5% of the expected value, then th

be repeated).

• Record flow rate, pump head, torque and speed at each point

• Calculate efficiency at each of the points

– BEP is determined by finding maximum of best fit curve of eff

flow rate

% of BEP

flow

Flow Rate

(GPM) Head (ft)

Speed

(RPM)

Torque

(lb‐in)

Hydraulic

Power

(hp)

Shaft input

power (hp) η (

128 1200.59 141.51 1774.10 1977.14 41.76 55.65 75108 1012.80 157.91 1774.63 1782.87 39.31 50.20 78100 939.62 162.58 1774.80 1721.36 37.55 48.47 77

91 851.24 169.44 1775.86 1613.80 35.46 45.47 7776 709.87 178.40 1775.85 1458.85 31.13 41.11 7558 547.19 186.61 1777.84 1251.15 25.10 35.29 7148 449.06 189.67 1778.80 1112.42 20.94 31.40 66
10

Pump Curve Example – Determining BEP

25% 50% 75% 100% 110% 

Percent of BEP Flow
11

Determining Bare Shaft Pump Input Power

– After determining BEP flow, part load power is determined th

regression of pump shaft input power vs flow rate for all data p

50% of BEP flow

• At very low part load, pump shaft input power vs flow rate curve 

• Using best fit linear regression, obtain pump shaft input power f

(QBEP, Q75%, Q110%)

y = 0.031x + 18.805

R2 = 0.9968

0

102030405060

0 500 1000 1500

Pump shaft input power (hp)

Flow rate (GPM)

Above 50% BEP flowBelow 50% BEP flow

% of BEP

flow

Flow R

(GPM

100 940 

75 705 

110 1034 

– Instead could linea

between points to input power at part 

– Could also establish 

which interpolation 
12

Pump Curve Example – Determining Bare Shaft Input P

25% 50% 75% 100% 110% 120%

Percent of BEP Flow
13

PER Test Procedure Options

Pump Configuration

Bare Pump* Bare Pump + Motor Bare Pump + 

Test Procedure Options

Tested BarePump +

Calculations

Tested bare pump

performance + DOE

minimum efficiency

motor with assumed

part load losses

Tested bare pump

performance +

manufacturer motor

with assumed part

load losses

Tested 

performance 

motor with as

lo

Tested PumpwithManufacturerMotor

N/A

Tested performance

of bare pump with

manufacturer motor

(wire to water)

Tested perfo

pump with 

motor (w

Tested Pumpwith Motorand Controls

N/A N/A

Tested perfo

pump with 

motor and c

syste

Pump Motor

Pump Control M

*Pumps sold with non‐electric drives could be rated as bare pumps
14

×

standardized motor

efficiency and default

part load curve

MOTOR

pump performance data

from pump test at rated

speed

Determining Bare Pump PERCL

×

standardized co

performance 

Controls

• Pi values are the linearly‐fit shaft input power to the pump (speed x torque) at 

• i = 75%, 100%, and 110% of flow rate at BEP of the pump

• Equal weighting

• Standardized Motor Performance

• Enclosed motor that is minimally compliant with DOE’s motor regulation

for general purpose motors (subtype I) for all pumps except ESCC and ge

motors (subtype II) for ESCC pumps

• HP used will be next HP above brake horsepower at 120% of BEP HP

• Poles will be based on speed at which pump is being rated

• Standardized Controls Performance

• Drive efficiency = 100% (since no drive)
15

• Determine bare shaft input power at Q75%, Q100% and Q110% of B

૚.૚࣓ ൅ ࡼࡱ࡮ࡸ ൅ ࡼࡱ࡮ࡼ ࡼࡱ࡮࣓ ൅ ૞ૠ.૙ࡸ ൅ ૞ૠ.૙ࡼ ૞ૠ.૙࣓ ൌ ࡸ࡯ࡾࡱࡼ

Determining Bare Pump Performance

Load Point Flow rate [GPM] Pump brake hp [HP]

Q110% 1034 50.89

Q100% 940 47.98

Q75% 705 40.69

ࡸ࡯ࡾࡱࡼ ൌ ૚ ૜ൗ ൈ ૝૙. ૟ૢ࢖ࢎ ൅ ࡸ૙.ૠ૞ ൅ ૚ ૜ൗ ൈ ૝ૠ. ૡૢ࢖ࢎ ൅ ࡼࡱ࡮ࡸ૜ ૚ ൅ ൗ ൈ 
16

Determining Part Load Motor Losses

The fractional motor losses at each load point i (Li) are calculated as the ra

motor losses (Lrated) multiplied by the part‐load loss factor (yi), which is calcubic polynomial* of the load fraction on the motor (xi):

ܮ ௜ൌ ܮ௔௥௧௘ௗ ∗ ݕ݅ ൌ ܮ௔௥௧௘ௗ ∗ ܽ∗ݔ௜ଷ ൅ܾ∗ݔ௜ଶ ൅ܿ∗ݔ ൅ ௜݀

ൌ ܮ௔௥௧௘ௗ ∗ ܽ ∗

ܲ௜

݁ݖܵ݅ݎ݋ݐ݋ܯ

ଷ

൅ܾ∗

ܲ௜

݁ݖܵ݅ݎ݋ݐ݋ܯ

ଶ

൅ܿ∗

ܲ௜

ݎ݋ݐ݋ܯ

Where:

• Li = the fractional load loss of the motor at load point i (hp);

• Lrated = the rated full load motor losses as determined in accorda

DOE test procedure for motors at 10 CFR 431 subpart B (hp);

• yi = the part‐load loss factor;

• xi = the load fraction for the motor at each load point i;

• Pi = the shaft input power to the bare shaft pump (hp);

• MotorSize = the nominal rated output power of the motor (hp); 

• i = Percentage of flow at the best efficiency point (BEP) of the pu

*A different cubic polynomial (i.e. different a, b, c, and d coefficients) are a

based on the rotating speed (2‐pole vs. 4‐pole) and motor design (ODP vs
17

Motor Losses Equation• Motor loss curves based on Motor Masters Database

• Different load loss curves for ODP/TEFC and 2‐pole/4

motors

• Other options?

y = 0.12x3 + 0.18x2 + 0.4x + 0.3

0

0.20.40.60.8

1

1.2

0 0.5 1 1.5

Fraction of full load power loss

Fraction of full load power

ODP motors at 3600 RPM

CuMPoPo
18

Accounting for Motor Losses

• Calculate the fractional load loss at each flow point using: ܮ ௜ൌ ܮ

– Where Li is the fractional load loss at each flow point in hp, Lfull,rated is the full 

determined in accordance with 10 CFR 431.25 (subpart B) in hp, and yi is the 

factor for each flow point

• Calculate the fractional input power as follows: ܲ௜௡௜ ൌ ܲ௜ ൅ ܮ௜

– Where Pi is the bare shaft input power in hp and the fractional load loss at ea

Lfull,rated is the full load losses determined in accordance with 10 CFR 431.25 (

– Calculate fractional input power as follows: Piin = Pi + Li

% BEP flow

Bare pump

shaft input

power (hp)

Load

fraction

(xi)

Part load loss

factor (yi)

Fractional load

loss (hp)

F

110 50.89 0.85 0.84 3.45 

100 47.98 0.80 0.80 3.27 

75 40.69 0.68 0.69 2.84 
19

Determining Bare Pump Performance ‐ Calcula

• Calculate PERCL by weighting each of the input power v

follows:

• PERCL is based on motor efficiency of 93.6%, obtained 

motor regulation (10 CFR 431.25)

• Then calculate PEICL as a ratio of the pump PERCL and t

for a minimally compliant pump:

ൌ ࡸ࡯ࡾࡱࡼ

૚

൅ ࢖ࢎ	૜૞ .૜૝ ૜

૚

൅ ࢖ࢎ	૞૛ .૚ ૜

૚

ࢎ	૞૜ .૝૞ ૜

࢖ࢎ	૚ૠ ૢ. ૝ൌ ࡸ࡯ࡾࡱࡼ

ൌ ࡸ࡯ࡵࡱࡼ

௅஼ܴܧܲ

௫௠௔ܴܧܲ

ൌ

݌49.71݄

௫௠௔ܴܧܲ
20

×

manufacturer motor

efficiency at full and part

load

MOTOR

Bare Pump + Motor Test Procedure

Ma

pai

wit

pump performance 

data from pump

test at rated speed

standardized

controls

performance = 1

Controls ×

MOTOR PUMP

Ma

me

p

standardized

controls

performance = 1

Controls

×

pump+motor performance data

A

B
21

Determining Bare Pump + Motor PERCL

• Calculate PER using the same method as for the bare shaft pum

– Incorporate the rated motor efficiency rather than DOE minimum 

• Pi values are the tested shaft input power to the pump (speed x 

each load point i

– i = 75%, 100%, and 110% of flow rate at BEP of the pump

– Equal weighting

• Manufacturer Motor Performance

– Lrated is the full load losses of a motor that is paired with the pump

• Standardized Controls Performance

– Drive efficiency = 100% (since no drive)

૚.૚࣓ ൅ ࡼࡱ࡮ࡸ ൅ ࡼࡱ࡮ࡼ ࡼࡱ࡮࣓ ൅ ૞ૠ.૙ࡸ ൅ ૞ૠ.૙ࡼ ૞ૠ.૙࣓ ൌ ࡸ࡯ࡾࡱࡼ

ࡸ࡯ࡾࡱࡼ ൌ ૚ ૜ൗ ൈ ૝૙. ૟ૢ࢖ࢎ ൅ ࡸ૙.ૠ૞ ൅ ૚ ૜ൗ ൈ ૝ૠ. ૡૢ࢖ࢎ ൅ ࡼࡱ࡮ࡸ૜ ૚ ൅ ൗ ൈ 
22

Determining Bare Pump + Motor Performance –Calculation Method

• Assume 60 hp motor with ηmotor,meas = 95% (Lfull,rated = 3.16 hp) and 

as before:

• Then calculate PEICL as a ratio of the pump PERCL and the PERmax f

compliant pump:

ൌ ࡸ࡯ࡾࡱࡼ

૚

൅ ࢖ࢎ	ૡૡ .૜ ૝૛

૚

൅ ࢖ࢎ	ૢ૝ .૙૞ ૜

૚

	૞૞ .૜૞ ૜

ࡾࡱࡼ ൌ ૝ૡ. ૢૠ	࢖ࢎ

% BEP flow

Bare pump

shaft input

power (hp)

Load

fraction

(xi)

Part load loss

factor (yi)

Fractional load

loss (hp)

Fr

110 50.89 0.85 0.84 2.66 100 47.98 0.80 0.80 2.51 

75 40.69 0.68 0.69 2.18 

ൌ ࡸ࡯ࡵࡱࡼ

௅஼ܴܧܲ

௫௠௔ܴܧܲ

ൌ

݌49.71݄

௫௠௔ܴܧܲ
23

pump performance from pump test at

rated and reduced speed

×

motor/drive performance

data

BC

VFD MOTOR

Controls MOTOR PUMP

Bare Pump + Motor + Controls Test Procedure

Ma

pai

mo

Ma

me

p

co

×

manufacturer or default

motor efficiency

A MOTOR

Ma

pai

with 

m

de

pump performance

data from pump test

at rated speed

default controls

performance

× Controls
24

Determining Bare Pump + Motor + Controls PE• Pump Performance

– Pi values are the tested shaft input power to the pump (speed x to

load point i

• i = 25%, 50%, 75%, and 100% of flow rate at BEP of the pump

• 100% of BEP flow is only tested point

• Equal weighting

• Motor Performance (Losses)

– Lrated is the full load losses of a motor that is paired with the pump 

sold with motors

• Controls Performance

– Benefit is captured in calculation of bare shaft input power

– Drive efficiency = 96%

ܲܧܴ ௅௏ൌ ߱.ଶହ ܲ௜௡.ଶହ ൅ ߱.ହ଴ ܲ௜௡.ହ଴ ൅ ߱଴.଻ହ ܲ௜௡଴.଻ହ ൅ ߱஻ா௉ ܲ௜௡஻ா௉

ൌ

14 ܲ.ଶହ ൅ ܮ.ଶହ ൅

14 ܲ.ହ଴ ൅ ܮ.ହ଴ ൅

14 ܲ଴.଻ହ ൅ ܮ଴.଻ହ ൅

14 ܲ஻ா௉ 

Where Pi, Li other than 100% BEP are obtained

from control load curve
25

0

50

100150200250300350

0 200 400 600 800 1000 1200 1400

Head (ft)

flow rate (GPM)

Original VFD New VFD LoExample Pum

Best Efficiency Poin20% of BEP Head

Realized potential savings

Unrealized savings

Control Load Curve• Proposed: load profile with a static offset

– Head with flow is offset: ܪ ൌ ߙܳଶ ൅ ܪௌ௧௔௧௜௖– Assume: static offset is 20% of BEP head (other offsets could be c

– Given QBEP and HBEP, the system curve becomes:

• ܪ ൌ 0.8 ுಳಶು

ொಳಶುమ ܳଶ ൅ 0.2ܪ஻ா௉

• This curve passes through both BEP and the pump head intercept at 
26

Control factor: VFD ‐ Calculations

• The flow at input power to the bare pump are available from th

pump performance:

• Using the control curve, the bare pump shaft input power at 75

flow (660 GPM) is:

• Applied to all rating points yields the following:

ࡳ	૙૝ૢ ൌࡼࡱ࡮ࡽ															;ܘܐ	ૡૢ .ૠ ૝ൌ ࡼࡱ࡮ࡼ

૚ࡼ

࢖ࢋ࢈ࡼ

࢖ࢋ࢈ࡽࡽ ૛ .૙ ൅ ૛ ࢖ࢋ࢈ࡽࡽ ૡ . ૙ൌ

૞ૠ.૙ࡼ

૝ૠ. ૢૡ	࢖ࢎ

ൌ ૙. ૡ

ࡹࡼࡳ	૞૙ૠࡹࡼࡳ	૙૝ૢ

૛

൅ ૙. ૛

ࡹࡼࡳ	૞૙ૠࡹࡼࡳ	૙૝ૢ

ࡼ૙.ૠ૞ ൌ ૝ૠ. ૢૡ	࢖ࢎ૙ . ૡ ૙. ૠ૞ ૛ ൅ ૙. ૛ ૙. ૠ૞ ൌ ૛૜. ૜ૢ	

ࢎ

Load Point Flow (GPM) Bare pump shaft

input power (hp)

QBEP 940 47.98

Q75% 705 23.39Q50% 470 9.60

Q25% 235 3.00
27

Control factor: VFD ‐ Calculations

• Assuming the motor is a 95% efficient motor (as befo

drive is 96% efficient, the controlled PER (PERVL) is th

• Then calculate PEIVL as a ratio of the pump PERVL and 

for a minimally compliant pump:

.૙ ൅ ࢖ࢎ	૜૛ .૟૛ ૞૛ .૙ ൅ ࢖ࢎ	૜ૠ . ૛૞ ૚૚.	 ൅ ૙࢖ࢎ	૞ૡ . ૛૞ 	૝. ૙ൌ ࡸࢂࡾࡱࡼ

࢖ࢎ	૞ૡ . ૛૜ൌ ࡸࢂࡾࡱࡼ

ൌ ࡸࢂࡵࡱࡼ

௅௏ܴܧܲ

௫௠௔ܴܧܲ

ൌ

݌23.85݄

௫௠௔ܴܧܲ
28

PER Calculation Comparison Summary• PER accounts for savings from control and from more 

motor

Equipment Configuration PER

Bare Pump 49.71Pump + 95% Eff. Motor 48.97

Pump + Motor + VSD 23.85
29

Overview of the Calculator• View Excel based PER_Calculator_v6

– Calculator is based on the calculation method just presente
30

Bare Pump + Motor – Test Method• Referred to as “string test” in HI 14.6

– Test similar to bare shaft test procedure,

except motor input power (Pin,i) is measured

directly

• If motor efficiency changes significantly from rated v

tested PER will vary from calculated value

MOTOR PUMP

Manu

measu

pum

c

standardized controls

performance

Controls ×

Pump+moto

data from 

rated 

ࡼ ૚.૚࣓ ൅ ࡼࡱ࡮,࢔࢏ࡼ ࡼࡱ࡮࣓ ൅ ૞ૠ.૙,࢔࢏ࡼ ૞ૠ.૙࣓ ൌ ࡾࡱࡼ
31

String test data (for pump + motor)• Input electrical power was measured for the exampl

used for the calculation of PER in earlier examples

Load Point Flow (GPM) String test input

power (hp)

Q110% 1034 53.58

QBEP 940 50.46

Q75% 705 42.71

Q50% 470 35.07Q25% 235 27.49

ൌ ࡾࡱࡼ

૚

൅ ࢖ࢎ	૚ૠ .૜ ૝૛

૚

൅ ࢖ࢎ	૟૝ .૙૞ ૜

૚

ࢎ	ૡ ૞.૜ ૞૜

࢚࢙ࢋ࢚ࡾࡱࡼ ൌ ૝ૡ. ૢ૛	࢖ࢎ ࢉ࢒ࢇࢉࡾࡱࡼ ൌ ૝ૡ. ૢૠ	࢖ࢎ
32

pump performance from pump test at

rated and reduced speed

×

motor/drive performance

data

BC

VFD MOTOR

Controls MOTOR PUMP

Bare Pump + Motor + Controls

Ma

pai

mo

Ma

me

p

co

×

manufacturer or default

motor efficiency

A MOTOR

Ma

pai

with 

m

de

pump performance

data from pump test

at rated speed

default controls

performance

Controls ×
33

 Calculation is similar to pump + motor approach, but use comb

efficiency of motor + drive as determined by AHRI 1210:

 Drive system efficiency determined through interpolation of AH

tested points (for example, assume values to fill map):

Determining Bare Pump + Motor + Controls PerformanAHRI 1210

6% 25% 56% 

131.25 525 1181.25 

25% 450 85% 

50% 900 88% 

75% 1350 93% 

100% 1800 

૞૛.࣓ ൌ ࡾࡱࡼ

૞૛.ࡼ

࢙ࢇࢋ࢓,ࢋ࢛࢜࢘ࢊη

૙૞.૙࣓ ൅

૙૞.૙ࡼ

࢙ࢇࢋ࢓,ࢋ࢜࢏࢘ࢊη

૞ૠ.૙࣓ ൅

૞ૠ.૙ࡼ

࢙ࢇࢋ࢓,ࢋ࢜࢏࢘ࢊη

ࡼࡱ࡮࣓ ൅

Speed (RPM)

Torque(lb-in)
34

Determining Bare Pump + Motor + Controls Performance –AHRI 1210 Linearly interpolate points from AHRI to pump load p

 Assumptions: 60 hp motor/VFD with a rated full load speed 

 Example calculation for Q75%

 Given 1312.5 RPM and 1455 lb‐in at Q75%, interpolate betwee

values from speed/torque map as follows:

ߟ଻ହ% ൌ ߟ n଻ହ%, T଻ହ% ൌ

93 െ 88

1350 െ 900 ∗ 1312.5 െ 900 ൅ 88 ൅ 98 െ 93 2100 െ 1181.25 ∗ 1455 

2

ߟ଻ହ% ൌ93.54%

Load

Point

Rated

Speed

(RPM)

Flow Rate Torque (lb‐in) Bare Pump Input Power (hp) Drive System Efficiency 

QBEP 1750 940 1722 47.98 96.69 

Q75% 1312.5 705 1455 23.39 93.54 Q50% 875 470 1142 9.60 90.27 Q25% 437.5 235 856 3.00 87.76 
35

Interpolating AHRI 1210 Drive Efficiencies• Applying this for both speed and torque and for all lo• Or can do a full train test and use tested input powe

• Note that PERtest should always be lower than PERcalc

൅ ࢖ࢎ	૝૟ .૙૚ ૞૛ .૙ ൅ ࢖ࢎ	૚૙ .૞૛	 ૞૛ .૙ ൅ ࢖ࢎ	૛૟ ૢ.૝ ૞૛ .૙ ൌ ࡾࡱࡼ

࢖ࢎ	૞ૡ . ૛૜ൌ ࢉ࢒ࢇࢉࡾࡱࡼ ࢖ࢎ	ૠ ૚. ૛૛ൌ ࢚࢙ࢋ࢚ࡾࡱࡼ
36

Application of Calculation and Testing Based M• Is physical testing more appropriate for some equipment classe

calculation method is more appropriate for others?

– e.g. ESCC pumps, pumps sold with motors not subject DOE standa

Test Method Pros ConsCalculationMethod

Repeatable;

Less burdensome

Does not differentiatcontrols performancAssumptions regardi

motor/controls efficichanging load requir

Decreased accuracy

Physical TestMethod

Accurate;Differentiates performance of

different motor/controlsequipment at full and part load

Burdensome;AHRI 1210 test data