BUILDING TECHNOLOGIE

April 29‐30, 20

ASRAC Pumps Working Group

Metric: Testing and Calculations
2

Primary Discussion Review of Metric and Relationship to Standard

 Overview of PER Test Procedure for Controlled versus Uncontro

Other Remaining Issues/Topics

 Test Procedure Options

• Calculation‐based method

- How to account for motor efficiency at part load and controls

• Testing‐based method

 Load Point Options

 Weighting Options Other Denominator Options

Overview
3

Metric Goals

1. Be objectively measureable

2. Represent the

performance of thecovered product

3. Differentiate performance among pump

models and pump configurations

(e.g. pumps sold with controls)

4. Communicate information

about pump performance tothe consumer

– May not be all the information

a consumer uses to make adecision

5. Compare the

efficiency ofa given pump

model to aminimum standard level

Metric

Test

Procedure

Tested

Performance

of Pump A

Tested

Performance

of Pump B

Bare Pump

Efficiency

or Energy

Use

Mot

Efficie

or En

Us

‘Pump’

Efficiency

or Energy

Use

=
4

Metric

Test

Procedure

Tested

Performance

of Pump A

Tested

Performance

of Pump B

Scope of Slides• This slide deck and the PER Calculator address how t

is calculated in the test procedure for a given pump 
5

Metric Applicability to Pump Configurations

Pump Configuration

Bare Pump* Bare Pump + Motor Bare Pump + 

Metric CoverageBare Pump MEI 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
6

PER Test Procedure

Pump Energy Rating (PER) CL and FL: equally weighted average el

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

present, controls input, over a specified load profile:

Where:

• PER = Pump Energy Rating (hp);

• wi = weight at each load point i;

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

if present, (hp);

• Denominator = minimally compliant uncontrolled pump; an

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

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

speed for uncontrolled pumps

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

pumps sold with motors and controls.

ൌ ࡸࢂ/ࡸ࡯ࡾࡱࡼ

∑ ߱௜ ܲ௜௡ ௜ ௜

݉ݑܲ	݈݈݁݀݋ݎݐ݊݋ܷ݊ܿ	ݐ݈݅ܽ݊݌݉݋ܥ	ݕ݈݈݅݊݅݉ܽܯ
7

Determining PERCL 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 w

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

and general purpose motors (subtype II) for ESCC pumps

ܲܧܴ ൌ 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௥௢,ଵ.ଵ

0.985 ∗ ߟ௣௨௠

=

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
8

Determining PERVL for a Controlled Pump

ൌ ܴܧܲ

1

η௖௧௥௟

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

߱଴.଻ହ

ܲு௬ௗ௥௢,଴.଻ହ

0.95 ∗ ߟ௣௨௠௣ ൅ ܮ଴.଻ହ ൅ ߱஻ா௉

ܲு௬ௗ௥௢,஻ா௉

ߟ௣௨௠௣ ൅ ܮ஻ா௉ ൅ ߱ଵ.ଵ

ܲ

0.98

=

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
9

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 ௡௜௠ൌ ߱଴.଻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
10

Options for Determining PERFL for a Controlled 

ൌ஼௅ ܴܧܲ

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

߱଴.଻ହ

ܲு௬ௗ௥௢,଴.଻ହ

0.95 ∗ ߟ௣௨௠௣ ൅ ܮ଴.଻ହ ൅ ߱஻ா௉

ܲு௬ௗ௥௢,஻ா௉

ߟ௣௨௠௣ ൅ ܮ஻ா௉ ൅ ߱ଵ.ଵ

ܲு௬ௗ௥

0.985 ∗ 

ൌ௏௅ ܴܧܲ

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

PER Constant Load PER Variable Load

PumpPerformance

Pi = measured shaft input power to the pump

(speed x torque) at each load point i

Where: i = 75%, 100%, and 110% of flow rate at

BEP of the pump and equal weighting

Pi = calculated shaft input p

based on affinity laws at ea

Where: i = 25%, 50%, 75%, at BEP of the pump and equ

MotorPerformance(Losses)

Lrated is the full load losses of a motor that is paired

with the pump for pumps sold with motors or the

full load losses of an enclosed motor that isminimally compliant with DOE’s motor regulations

(10 CFR 431.25) for general purpose motors

(subtype I) for all pumps except ESCC and general

purpose motors (subtype II) for ESCC pumps

Lrated is the full load losses o

paired with the pump and lfor the reduced loading wit

ControlsPerformance

No controls Benefit is captured in calcul

input power.

Drive efficiency = 96%
11

Items to Discuss at the Next Meeting/Webinar 

• Metric nomenclature

• Comparison of MEI and PER

• Impact of test procedure and metric on standard

• Definition of basic model• Examples for different pump configurations and revise• Implementation of PERCL and PERVL

– Labeling/marking logistics, including sales and distribution ch

– Additional reported information or label information

– Who is the manufacturer?

– Market impacts, especially application to utility programs

• Motor and driver part load loss factor

• Testing vs calculation options• Testing burden• Certification and enforcement issues
12

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

losses + Load 

Tested Pump

withManufacturerMotor

N/A

Tested performance

of bare pump with

manufacturer motor

(wire to water)

Tested perfo

pump with 

motor (wire t

Contr

Tested Pump

with 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
13

Accounting for 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
14

“Denominator” Options

“Denominator” Units Pros ConsNo Denominator Hp or kWh

Representative of the energy

consumption of that pump in thefield.Strong function of flow and specific

speed.

Not comparabl

different flows/

Less strong funspecific speed.

Reference shaft power

for minimally

compliant bare pumpwith minimally

compliant motor

Dimensionless

Results in value between 0 and 1

(more intuitive).Clearly indicates performance of a

pump relative to a baseline.

Inherently requ

minimally comp

MEI). May ovethe baseline eff

pumps.

Market average shaft

power with minimally

compliant or market

average motor

Dimensionless Indicates performance of a pump

relative to the market.

Locks in the me

performance of market at a give

Doesn’t limit m

0 and 1.

Tested pump’s

hydraulic power at

BEP

Dimensionless

Accounts for differences in pump

efficiencies between models.

Has similar rated values for pumpsof different sizes.

Lower PER ratin

because lower 

is inherently les
15

Determining Pump Input Power

Power input to the pump at a specific load point (Pini) can be:

(A) measured using a wire to water test; or

(B) calculated as the power input to the pump (Pi) plus the motor 

that load point:

Where:

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

controls if present (hp);

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

• Li = the fractional load motor losses (hp); and

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

Expanding the PER equation yields the following equation:

௜ܮ ൅ ௜ܲ ൌ௜௡௜ ܲ

ݎ݋ݐ݉݅݊ܽ݋݁݊ܦ ௜ܮ ൅ ௜ܲ ௜߱ ௜∑ ܨܥܮ ൌ ܴܧܲ
16

Testing Bare Pump Performance

Perform HI 40.6 to determine bare shaft input power at each load point i:

• 7 points swept from shutoff to maximum flow rate, with flow rate (GPM

rotational speed (rpm), torque (in‐lbf) recorded in following table

• Hydraulic pump efficiency is calculated at each flow point

– Input power = (torque) x (speed)

– Output power = (flow rate) x (head) x (specific weight of fluid)

– Efficiency = output power / input power

• BEP found by determining maximum of best fit curve of efficiency with 

rate

• Bare shaft input power at each load point found by interpolating perfor

pump curve at 75% and 110% of BEP flow

% 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 7108 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 45.47 776 709.87 178.40 1775.85 1458.85 31.13 41.11 758 547.19 186.61 1777.84 1251.15 25.10 35.29 748 449.06 189.67 1778.80 1112.42 20.94 31.40 6
17

×

standardized motor

efficiency and default

part load curve

MOTOR

pump performance data

from pump test at rated

speed

Determining Bare Pump PER

×

standardized co

performance 

Controls

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

• 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

• LCF = 1 (no controls)

• Drive efficiency = 100% (since no drive)
18

×

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
19

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
20

Load Control Factor: Basis

 LCF is defined as the ratio of PER of a speed controlled pump to 

uncontrolled pump

• ܨܥܮ ൌ 	 ௉ாோ಴೚೙೟ೝ೚೗೗೐೏

௉ாோೆ೙೎೚೙೟ೝ೚೗೗೐೏

• Load control factor for the VFD provided in PER calculation examp

depending on load profile and weighting

 PER of pump+motor will be used to determine the LCF for each 

 Use an assumed conservative system curve for all three options 

variations to determine the Load Control Factor

 Assumptions:

• Efficiency of control = 96%

૚ࡽ૛ࡽ

ൌ

૚࢔૛࢔

૚ࡴ૛ࡴ

ൌ

૚࢔૛࢔

૚ࡼ ૛૛ࡼ

ൌ

૚࢔૛࢔

૜
21

Load Control Factor Options• Other control options to be considered?• Make LCF a function of efficiency to distinguish simil

options with different efficiencies?

Control Efficiency of Control Other Assumptions 

VFD 96% Follow defined system curve 

ECM 96% 2‐speed motor 96%

25% and 50% load point are at

lower speed & 75% and 100%load points are at full speed
22

Options for Determining PERFL for a Controlled 

ܨܥܮ ൌ ܴܧܲ

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

௡௜௠ܴܧܲ

ൌ

1

η௖௧௥௟

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

߱଴.଻ହ

ܲு௬ௗ௥௢,଴.଻ହ

0.95 ∗ ߟ௣௨௠௣ ൅ ܮ଴.଻ହ ൅ ߱஻ா௉

ܲு௬ௗ௥௢,஻ா௉

ߟ௣௨௠௣ ൅ ܮ஻ா௉ ൅ ߱ଵ.ଵ

ܲு௬ௗ

0.985 

LCF Approach Full Calculation Approach

PumpPerformance

Pi = measured shaft input power to the pump

(speed x torque) at each load point i

Where: i = 75%, 100%, and 110% of flow rate at

BEP of the pump and equal weighting

Pi = calculated shaft input p

based on affinity laws at ea

Where: i = 25%, 50%, 75%, 

rate at BEP of the pump and 

MotorPerformance(Losses)

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

reduced loading with speed reduction

ControlsPerformance

LCF = 0.56 for VFD control, 0.67 for 2‐speed

motor, etc.

Accounts for reduced power input at load points

of 25%, 50%, 75% and 100% of BEP flow

Drive efficiency = 96%

Benefit is captured in calcul

input power.

Could still account for drive