数字平面电视的电源设计技术要求分析

数字平面电视的电源设计技术要求分析 上网时间: 2008年05月23日

数位平面电视持续成长，2008年可望在全球电视市场取得超过50%的比例。平面电视(包括电浆电视和液晶电视)的电源设计与传统的阴极射线管(CRT)电视有很大不同。首要挑战是使电源配合平面电视纤薄的面板形状，其次是管理视讯电路的发热和电磁干扰(EMI)问题。与CRT的要求相较，平面电视所要求的电平较高，且要求的电压也不同，因此使电源设计问题更复杂。若将显示面板的成本排除在外，电源占据液晶电视材料清单(BOM)成本约12%。而从实体尺寸来看，电源也占了液晶电视屏幕背面区域颇大的一部份(见图1)。

图1：46英吋液晶电视面板背部剖面图。(资料来源：iSuppli)

图2为传统液晶电视系统架构图，其中绿色突出显示部份为电源系统模块。前端是交流-直流(AC-DC)转换器，负责接收通用交流输入(90-265V_rms)， 并在应用前端的功率因子校正(PFC)功能后，将交流电压转换为单路或多任务隔离的直流电压。对屏幕尺寸较小的液晶电视而言，如果其功率输入低于 75W，PFC就不是一项强制要求。AC-DC转换器产生的其中一路主电压(典型值为24V)主要负责为背光转换器供电，而其电流/功率要求取决于显示器 所使用的冷阴极荧光灯(CCFL)的灯管数量(屏幕尺寸越大，功率要求越高)。在大尺寸液晶电视中，背光能占超过80%的总功耗。自AC-DC转换器输出 的第二路重要电压是用于音讯子系统和下行系统电源的12V输出，其中下行系统电源在一个经DC-DC转换之后为低压讯号处理电路和处理器供电。小尺寸液晶 电视可使用12V电源进行背光和为音讯放大器供电。此外还要求一个具有高达2A电流能力的5V待机电源。

图2：典型的液晶电视功能模块图，其中绿色显示部份为电源处理模块。

系统要求的所有其它电压都是采用低压降(LDO)稳压器或DC-DC转换器为其它处理功能供电，这些处理功能的实体位置和选择取决于目前的要求和尺寸限制。

典型电源平台

根 据面板尺寸、面板制造商、音讯要求和所用的芯片组等因素的不同，各个电源设计要求也会不同，但对于电视制造商和其电源原设计制造商(ODM)而言，他们需 要的是标准平台，能够快速适用于不同的要求(如某平台用于尺寸最大为26英吋的液晶电视，另一种用于尺寸介于26至32英吋之间的液晶电视，依此类推)。 平台的选择主要由成本因素来确定。由于小屏幕尺寸(小于26英吋，功率小于150W)设计功率较低，且对成本更敏感，它们多由简单的反驰式设计主导。如果 需要PFC，便会采用临界导电模式(CrM)电路，将成本降到最低。然而，如要求低EMI和高能效，便须采用谷底转换(valley- switching)或准谐振反驰技术。将电视内部的发热降到最低也很重要，因为液晶电视采用被动冷却方式，而且电视机内部的顶端和底端存在的显著温差可 能会影响CCFL灯管光输出的一致性。业界已经证明，采用适当的半导体解决方案，从传统的固频反驰转向谷底转换的成本影响可说是微不足道。低阶设计中整合 了单个12V输出电源，并使用后处理器(post-processor)来产生5V电源。在这种方法中，待机管理比较棘手，因为需要额外的负载开关。

另 一个平台等级适用于26至37英吋电视，功率介于150和250W之间。对于这些系统，电源板内必须含有一个独立的待机转换器，否则要在0.5W负载下满 足小于1W输入功率的待机要求就变得很困难。此外，还须转换为24V输出电压以用于背光转换器。其它讯号处理电路和音讯仍然需要12V总线，因此典型使 用的是多输出转换器。虽然传统的和较低阶的平台仍然在主转换器和待机转换器中使用反驰拓朴，但如今趋向利用双电感加单电容(LLC)半桥转换器的软开关拓朴来提高能效及减少EMI。

对 高于250W的更大屏幕尺寸(大于37英吋)而言，在主电源中使用LLC半桥转换器就更为平常了。而且PFC功能通常是采用连续导电模式(CCM)电路来 实现，电平和要求的复杂程度都有增加。因此，辅助电源透过反驰转换器来处理。主电源的第二个输入端提供高达14V电压，以支持更高的音讯功率要求。

PFC概述

虽 然PFC应用的推动力主要是欧洲有关谐波减少的标准IEC61000-3-2，主动PFC前端的额外效益使其几乎成为绝大多数平面电视的通用选择。这与 CRT电视形成了鲜明对比，因为在CRT电视中PFC解决方案主要是被动、大体积的方案。随着近来NCP1653等简化型CCM控制器和相关支持组件的推 出，PFC前端的设计挑战已经得到舒解。如上所述，低阶解决方案的共同选择就是CrM拓朴结构，例如NCP1606控制器等。然而，近期出现一个变化─频 率钳位CrM方法(如NCP1605)正凭借其改善的待机管理和更低的EMI而受到欢迎。

为平面显示应用选择PFC拓朴结构时，考虑诸如电源段的排序、保持时间、输出电压范围、待机和轻载下工作等问题也很重要。

LLC半桥概述

主电源段适合拓朴结构的选择取决于电平、设计人员熟悉程度和输出要求等因素。表1提供了适合不同屏幕尺寸的不同解决方案。

表1：不同屏幕尺寸的开关电源拓朴结构选择

这 种拓朴结构因消除导通开关损耗而显著提高电源效率。此外，如图3所示，这种结构与其它谐振方式不同，它不需要输出电感，相对比较简单。谐振回路能够透过将 谐振电感整合在主变压器中得到简化。它还将开关电压应力限制到输入电压的最大值。这些优点使LLC半桥转换器拓朴结构成为大功率LCD和电浆电视电源设计 非常便利的选择。由于开关频率并不会显著变化，存在着稳定的PFC电压端简化了设计过程。然而，使用这种拓朴结构来设计电源需要一些特别的考虑和设计折 衷，其中包括谐振回路、输入和输出电容的选择，以及变压器的设计。使用LLC半桥拓朴结构已经被证明能够实现高于90%的能效。

图3：LLC半桥转换器的简化原理示意图。

新兴架构及趋势

随着液晶电视市场的高速成长，业界面临着建构更高性价比及更高能效电源的压力，目前有两大主要发展方向。

首先是市场已体认到输出电压范围的差异性可提供特定市场定制电源的商机。举例来说，单独针对北美市场设计电源会将输入电压范围限制在90~132V_rms，并消除了PFC强制要求，这会使成本显著下降并可最佳化电源。同理，如针对欧洲电源要求，具有PFC的设计能够实现最佳化设计。

第 二个重要的架构趋势是将背光转换器整合在电源中，也就是大家所知的LCD整合电源(LIPS)。这种方法消除了用于背光转换器的24V电源端需求，改从 PFC输出电压(390V)直接为转换器供电。这将降低系统总功率、减少主板发热量并降低成本。然而，由于涉及融合电视机的两个不同部份，且这两部份的采 购来源各不相同(一个来自面板供货商，另一个来自电源ODM)，从供应链管理来看，这种趋势存在着挑战，因为电源必须针对特定面板制造商和灯管配置进行最 佳化。

解决方案示例

本文所列举的新要求显示要满足这些新要求对电视制造商及其供 应商而言都是持续的挑战，加上极短的设计周期，电视制造商通常选用经过验证的平台。安森美半导体率先针对这些液晶电视电源要求积极提供完整的参考设计解决 方案，这些参考设计结合了经过验证并符合所有系统要求的完整解决方案。图4显示了其中一个参考设计。

图4：用于220W液晶电视电源的安森美半导体GreenPoint参考设计。

该 参考设计包含一个PFC，它整合了频率钳位CrM拓朴结构，具备良好的待机性能，并且使用跳周期模式作业在输出维持稳健的电压端。它还有一个使用了 NCP1027稳压器的待机电源，用于5V、2.5A输出。而LLC半桥转换器产生三路输出(用于背光的24V、6A输出；用于面板和音讯功能的12V、 3A输出；30V、1A输出)。在输入电压为230V_ac时，该参考设计能效高于90%，而在待机0.5W负载时其输入功率证明低于1W。它符合IEC61000-3-2的谐波要求。

本文小结

本 文简述了平面电视电源架构的新兴电源设计挑战和发展趋势。这些趋势源自于降低功耗以管理发热、减少EMI和永?琲沪饥C成本的要求。随着电视制造商争相推 出更纤薄的LCD面板，这方面的挑战也变得更棘手。许多变化来自背光技术，如具有LIPS的CCFL、外置电极荧光灯(EEFL)或者甚至是红绿蓝 (RGB) LED光源。未来几年内，这些变化必使电源设计人员保持警觉，驱使他们持续提供更创新的解决方案。最后，液晶电视日趋普及的程度已引起标准制订机构的注 意，这些机构正考虑在不远的将来制订相关的能耗标准。

作者：Dhaval Dalal

电源供应器系统工程总监

Bernie Weir

电源调节产品经理

安森美半导体公司

此文章源自《电子工程专辑》网站： http://www.eettaiwan.com/ART_8800523809_675763_TA_1cdb90ca.HTM

外汇汇率换算

奇摩雅虎银行服务
google finance

单位换算

SI Units

From http://physics.nist.gov/Pubs/SP811/appenB9.html

B. 9 Factors for units listed by kind of quantity or field of science

Note: Some links are not underlined on this page to improve readability.

ACCELERATION ANGLE AREA AND SECOND MOMENT OF AREA CAPACITY (see VOLUME) DENSITY (that is, MASS DENSITY - see MASS DIVIDED BY VOLUME) ELECTRICITY and MAGNETISM ENERGY (includes WORK) ENERGY DIVIDED BY AREA TIME FLOW (see MASS DIVIDED BY TIME or VOLUME DIVIDED BY TIME) FORCE FORCE DIVIDED BY AREA (see PRESSURE) FORCE DIVIDED BY LENGTH HEAT Available Energy Coefficient of Heat Transfer Density of Heat Density of Heat Flow Rate Fuel Consumption Heat Capacity and Entropy Heat Flow Rate Specific Heat Capacity and Specific Entropy Thermal Conductivity Thermal Diffusivity Thermal Insulance Thermal Resistance Thermal Resistivity

LENGTH LIGHT MASS and MOMENT OF INERTIA MASS DENSITY (see MASS DIVIDED BY VOLUME) MASS DIVIDED BY AREA MASS DIVIDED BY CAPACITY (see MASS DIVIDED BY VOLUME) MASS DIVIDED BY LENGTH MASS DIVIDED BY TIME (includes FLOW) MASS DIVIDED BY VOLUME (includes MASS DENSITY and MASS CONCENTRATION) MOMENT OF FORCE or TORQUE MOMENT OF FORCE or TORQUE, DIVIDED BY LENGTH PERMEABILITY POWER PRESSURE or STRESS (FORCE DIVIDED BY AREA) RADIOLOGY SPEED (see VELOCITY) STRESS (see PRESSURE) TEMPERATURE TEMPERATURE INTERVAL TIME TORQUE (see MOMENT OF FORCE) VELOCITY (includes SPEED) VISCOSITY, DYNAMIC VISCOSITY, KINEMATIC VOLUME (includes CAPACITY) VOLUME DIVIDED BY TIME (includes FLOW) WORK (see ENERGY)

---

Caution: The units listed in column 1 are in general not to be used in NIST publications, with the exception of those few in italic type.

Factors in boldface are exact

ACCELERATION
To convert from	to	Multiply by
acceleration of free fall, standard (gn) 28	meter per second squared (m/s2)	9.806 65	E+00
foot per second squared (ft/s2)	meter per second squared (m/s2)	3.048	E-01
gal (Gal)	meter per second squared (m/s2)	1.0	E-02
inch per second squared (in/s2)	meter per second squared (m/s2)	2.54	E-02

ANGLE
To convert from	to	Multiply by
degree (°)	radian (rad)	1.745 329	E-02
gon (also called grade) (gon)	radian (rad)	1.570 796	E-02
gon (also called grade) (gon)	degree (°)	9.0	E-01
mil	radian (rad)	9.817 477	E-04
mil	degree (°)	5.625	E-02
minute (′ )	radian (rad)	2.908 882	E-04
revolution (r)	radian (rad)	6.283 185	E+00
second (″ )	radian (rad)	4.848 137	E-06

AREA AND SECOND MOMENT OF AREA
To convert from	to	Multiply by
acre (based on U.S. survey foot) 9	square meter (m2)	4.046 873	E+03
are (a)	square meter (m2)	1.0	E+02
barn (b)	square meter (m2)	1.0	E-28
circular mil	square meter (m2)	5.067 075	E-10
circular mil	square millimeter (mm2)	5.067 075	E-04
foot to the fourth power (ft4) 17	meter to the fourth power (m4)	8.630 975	E-03
hectare (ha)	square meter (m2)	1.0	E+04
inch to the fourth power (in4) 17	meter to the fourth power (m4)	4.162 314	E-07
square foot (ft2)	square meter (m2)	9.290 304	E-02
square inch (in2)	square meter (m2)	6.4516	E-04
square inch (in2)	square centimeter (cm2)	6.4516	E+00
square mile (mi2)	square meter (m2)	2.589 988	E+06
square mile (mi2)	square kilometer (km2)	2.589 988	E+00
square mile (based on U.S. survey foot) (mi2) 9	square meter (m2)	2.589 998	E+06
square mile (based on U.S. survey foot) (mi2) 9	square kilometer (km2)	2.589 998	E+00
square yard (yd2)	square meter (m2)	8.361 274	E-01
CAPACITY (see VOLUME) DENSITY (that is, MASS DENSITY - see MASS DIVIDED BY VOLUME)

ELECTRICITY and MAGNETISM
To convert from	to	Multiply by
abampere	ampere (A)	1.0	E+01
abcoulomb	coulomb(C)	1.0	E+01
abfarad	farad (F)	1.0	E+09
abhenry	henry (H)	1.0	E-09
abmho	siemens (S)	1.0	E+09
abohm	ohm (Ω)	1.0	E-09
abvolt	volt (V)	1.0	E-08
ampere hour (A · h)	coulomb(C)	3.6	E+03
biot (Bi)	ampere (A)	1.0	E+01
EMU of capacitance (abfarad)	farad (F)	1.0	E+09
EMU of current (abampere)	ampere (A)	1.0	E+01
EMU of electric potential (abvolt)	volt (V)	1.0	E-08
EMU of inductance (abhenry)	henry (H)	1.0	E-09
EMU of resistance (abohm)	ohm (Ω)	1.0	E-09
ESU of capacitance (statfarad)	farad (F)	1.112 650	E-12
ESU of current (statampere)	ampere (A)	3.335 641	E-10
ESU of electric potential (statvolt)	volt (V)	2.997 925	E+02
ESU of inductance (stathenry)	henry (H)	8.987 552	E+11
ESU of resistance (statohm)	ohm (Ω)	8.987 552	E+11
faraday (based on carbon 12)	coulomb(C)	9.648 531	E+04
franklin (Fr)	coulomb(C)	3.335 641	E-10
gamma (γ)	tesla (T)	1.0	E-09
gauss (Gs, G)	tesla (T)	1.0	E-04
gilbert (Gi)	ampere (A)	7.957 747	E-01
maxwell (Mx)	weber (Wb)	1.0	E-08
mho	siemens (S)	1.0	E+00
oersted (Oe)	ampere per meter (A/m)	7.957 747	E+01
ohm centimeter (Ω · cm)	ohm meter (Ω · m)	1.0	E-02
ohm circular-mil per foot	ohm meter (Ω · m)	1.662 426	E-09
ohm circular-mil per foot	ohm square millimeter per meter (Ω · mm2/m)	1.662 426	E-03
statampere	ampere (A)	3.335 641	E-10
statcoulomb	coulomb (C)	3.335 641	E-10
statfarad	farad (F)	1.112 650	E-12
stathenry	henry (H)	8.987 552	E+11
statmho	siemens (S)	1.112 650	E-12
statohm	ohm(Ω)	8.987 552	E+11
statvolt	volt (V)	2.997 925	E+02
unit pole	weber (Wb)	1.256 637	E-07

ENERGY (includes WORK)
To convert from	to	Multiply by
British thermal unitIT (BtuIT) 11	joule (J)	1.055 056	E+03
British thermal unitth (Btuth) 11	joule (J)	1.054 350	E+03
British thermal unit (mean) (Btu)	joule (J)	1.055 87	E+03
British thermal unit (39 °F) (Btu)	joule (J)	1.059 67	E+03
British thermal unit (59 °F) (Btu)	joule (J)	1.054 80	E+03
British thermal unit (60 °F) (Btu)	joule (J)	1.054 68	E+03
calorieIT (calIT) 11	joule (J)	4.1868	E+00
calorieth (calth) 11	joule (J)	4.184	E+00
calorie (mean) (cal)	joule (J)	4.190 02	E+00
calorie (15 °C) (cal15)	joule (J)	4.185 80	E+00
calorie (20 °C) (cal20)	joule (J)	4.181 90	E+00
calorieIT, kilogram (nutrition) 12	joule (J)	4.1868	E+03
calorieth, kilogram (nutrition) 12	joule (J)	4.184	E+03
calorie (mean), kilogram (nutrition) 12	joule (J)	4.190 02	E+03
electronvolt (eV)	joule (J)	1.602 177	E-19
erg (erg)	joule (J)	1.0	E-07
foot poundal	joule (J)	4.214 011	E-02
foot pound-force (ft · lbf)	joule (J)	1.355 818	E+00
kilocalorieIT (kcalIT)	joule (J)	4.1868	E+03
kilocalorieth (kcalth)	joule (J)	4.184	E+03
kilocalorie (mean) (kcal)	joule (J)	4.190 02	E+03
kilowatt hour (kW · h)	joule (J)	3.6	E+06
kilowatt hour (kW · h)	megajoule (MJ)	3.6	E+00
quad (1015 BtuIT) 11	joule (J)	1.055 056	E+18
therm (EC) 25	joule (J)	1.055 06	E+08
therm (U.S.) 25	joule (J)	1.054 804	E+08
ton of TNT (energy equivalent) 26	joule (J)	4.184	E+09
watt hour (W · h)	joule (J)	3.6	E+03
watt second (W · s)	joule (J)	1.0	E+00

ENERGY DIVIDED BY AREA TIME
To convert from	to	Multiply by
erg per square centimeter second [erg/(cm2 · s)]	watt per square meter (W/m2)	1.0	E-03
watt per square centimeter (W/cm2)	watt per square meter (W/m2)	1.0	E+04
watt per square inch (W/in2)	watt per square meter (W/m2)	1.550 003	E+03
FLOW (see MASS DIVIDED BY TIME or VOLUME DIVIDED BY TIME)

FORCE
To convert from	to	Multiply by
dyne (dyn)	newton (N)	1.0	E-05
kilogram-force (kgf)	newton (N)	9.806 65	E+00
kilopond (kilogram-force) (kp)	newton (N)	9.806 65	E+00
kip (1 kip = 1000 lbf)	newton (N)	4.448 222	E+03
kip (1 kip = 1000 lbf)	kilonewton (kN)	4.448 222	E+00
ounce (avoirdupois)-force (ozf)	newton (N)	2.780 139	E-01
poundal	newton (N)	1.382 550	E-01
pound-force (lbf) 24	newton (N)	4.448 222	E+00
pound-force per pound (lbf/lb) (thrust to mass ratio)	newton per kilogram (N/kg)	9.806 65	E+00
ton-force (2000 lbf)	newton (N)	8.896 443	E+03
ton-force (2000 lbf)	kilonewton (kN)	8.896 443	E+00
FORCE DIVIDED BY AREA (see PRESSURE)

FORCE DIVIDED BY LENGTH
To convert from	to	Multiply by
pound-force per foot (lbf/ft)	newton per meter (N/m)	1.459 390	E+01
pound-force per inch (lbf/in)	newton per meter (N/m)	1.751 268	E+02

HEAT Available Energy
To convert from	to	Multiply by
British thermal unitIT per cubic foot (BtuIT/ft3)	joule per cubic meter (J/m3)	3.725 895	E+04
British thermal unitth per cubic foot (Btuth/ft3)	joule per cubic meter (J/m3)	3.723 403	E+04
British thermal unitIT per pound (BtuIT/lb)	joule per kilogram (J/kg)	2.326	E+03
British thermal unitth per pound (Btuth/lb)	joule per kilogram (J/kg)	2.324 444	E+03
calorieIT per gram (calIT/g)	joule per kilogram (J/kg)	4.1868	E+03
calorieth per gram (calth/g)	joule per kilogram (J/kg)	4.184	E+03

Coefficient of Heat Transfer
To convert from	to	Multiply by
British thermal unitIT per hour square foot degree Fahrenheit [BtuIT/(h · ft2 · °F)]	watt per square meter kelvin [W/(m2 · K)]	5.678 263	E+00
British thermal unitth per hour square foot degree Fahrenheit [Btuth/(h · ft2 · °F)]	watt per square meter kelvin [W/(m2 · K)]	5.674 466	E+00
British thermal unitIT per second square foot degree Fahrenheit [BtuIT/(s · ft2 · °F)]	watt per square meter kelvin [W/(m2 · K)]	2.044 175	E+04
British thermal unitth per second square foot degree Fahrenheit [Btuth/(s · ft2 · °F)]	watt per square meter kelvin [W/(m2 · K)]	2.042 808	E+04

Density of Heat
To convert from	to	Multiply by
British thermal unitIT per square foot (BtuIT/ft2)	joule per square meter (J/m2)	1.135 653	E+04
British thermal unitth per square foot (Btuth/ft2)	joule per square meter (J/m2)	1.134 893	E+04
calorieth per square centimeter (calth/cm2)	joule per square meter (J/m2)	4.184	E+04
langley (calth/cm2)	joule per square meter (J/m2)	4.184	E+04

Density of Heat Flow Rate
To convert from	to	Multiply by
British thermal unitIT per square foot hour [BtuIT/(ft2 · h)]	watt per square meter (W/m2)	3.154 591	E+00
British thermal unitth per square foot hour [Btuth/(ft2 · h)]	watt per square meter (W/m2)	3.152 481	E+00
British thermal unitth per square foot minute [Btuth/(ft2 · min)]	watt per square meter (W/m2)	1.891 489	E+02
British thermal unitIT per square foot second [BtuIT/(ft2 · s)]	watt per square meter (W/m2)	1.135 653	E+04
British thermal unitth per square foot second [Btuth/(ft2 · s)]	watt per square meter (W/m2)	1.134 893	E+04
British thermal unitth per square inch second [Btuth/(in 2 · s)]	watt per square meter (W/m2)	1.634 246	E+06
calorieth per square centimeter minute [calth/(cm2 · min)]	watt per square meter (W/m2)	6.973 333	E+02
calorieth per square centimeter second [calth/(cm2 · s)]	watt per square meter (W/m2))	4.184	E+04

Fuel Consumption
To convert from	to	Multiply by
gallon (U.S.) per horsepower hour [gal/(hp · h)]	cubic meter per joule (m3/J)	1.410 089	E-09
gallon (U.S.) per horsepower hour [gal/(hp · h)]	liter per joule (L/J)	1.410 089	E-06
mile per gallon (U.S.) (mpg) (mi/gal)	meter per cubic meter (m/m3)	4.251 437	E+05
mile per gallon (U.S.) (mpg) (mi/gal)	kilometer per liter (km/L)	4.251 437	E-01
mile per gallon (U.S.) (mpg) (mi/gal) 22	liter per 100 kilometer (L/100 km)	divide 235.215 by number of miles per gallon
pound per horsepower hour [lb/(hp · h)]	kilogram per joule (kg/J)	1.689 659	E-07

Heat Capacity and Entropy
To convert from	to	Multiply by
British thermal unitIT per degree Fahrenheit (BtuIT/°F)	joule per kelvin (J/K)	1.899 101	E+03
British thermal unitth per degree Fahrenheit (Btuth/°F)	joule per kelvin (J/K)	1.897 830	E+03
British thermal unitIT per degree Rankine (BtuIT/°R)	joule per kelvin (J/K)	1.899 101	E+03
British thermal unitth per degree Rankine (Btuth/°R)	joule per kelvin (J/K)	1.897 830	E+03

Heat Flow Rate
To convert from	to	Multiply by
British thermal unitIT per hour (BtuIT/h)	watt (W)	2.930 711	E-01
British thermal unitth per hour (Btuth/h)	watt (W)	2.928 751	E-01
British thermal unitth per minute (Btuth/min)	watt (W)	1.757 250	E+01
British thermal unitIT per second (BtuIT/s)	watt (W)	1.055 056	E+03
British thermal unitth per second (Btuth/s)	watt (W)	1.054 350	E+03
calorieth per minute (calth/min)	watt (W)	6.973 333	E-02
calorieth per second (calth/s)	watt (W)	4.184	E+00
kilocalorieth per minute (kcalth/min)	watt (W)	6.973 333	E+01
kilocalorieth per second (kcalth/s)	watt (W)	4.184	E+03
ton of refrigeration (12 000 BtuIT/h)	watt (W)	3.516 853	E+03

Specific Heat Capacity and Specific Entropy
To convert from	to	Multiply by
British thermal unitIT per pound degree Fahrenheit [BtuIT/(lb · °F)]	joule per kilogram kelvin [J/(kg · K)]	4.1868	E+03
British thermal unitth per pound degree Fahrenheit [Btuth/(lb · °F)]	joule per kilogram kelvin [J/(kg · K)]	4.184	E+03
British thermal unitIT per pound degree Rankine [BtuIT/(lb · °R)]	joule per kilogram kelvin [J/(kg · K)]	4.1868	E+03
British thermal unitth per pound degree Rankine [Btuth/(lb · °R)]	joule per kilogram kelvin [J/(kg · K)]	4.184	E+03
calorieIT per gram degree Celsius [calIT/(g · °C)]	joule per kilogram kelvin [J/(kg · K)]	4.1868	E+03
calorieth per gram degree Celsius [calth/(g · °C)]	joule per kilogram kelvin [J/(kg · K)]	4.184	E+03
calorieIT per gram kelvin [calIT/(g · K)]	joule per kilogram kelvin [J/(kg · K)]	4.1868	E+03
calorieth per gram kelvin [calth/(g · K)]	joule per kilogram kelvin [J/(kg · K)]	4.184	E+03

Thermal Conductivity
To convert from	to	Multiply by
Britsh thermal unitIT foot per hour square foot degree Fahrenheit [BtuIT · ft/(h · ft2 · °F)]	watt per meter kelvin [W/(m · K)]	1.730 735	E+00
Britsh thermal unitth foot per hour square foot degree Fahrenheit [Btuth · ft/(h · ft2 · °F)]	watt per meter kelvin [W/(m · K)]	1.729 577	E+00
Britsh thermal unitIT inch per hour square foot degree Fahrenheit [BtuIT · in/(h · ft2 · °F)]	watt per meter kelvin [W/(m · K)]	1.442 279	E-01
Britsh thermal unitth inch per hour square foot degree Fahrenheit [Btuth · in/(h · ft2 · °F)]	watt per meter kelvin [W/(m · K)]	1.441 314	E-01
Britsh thermal unitIT inch per second square foot degree Fahrenheit [BtuIT · in/(s · ft2 · °F)]	watt per meter kelvin [W/(m · K)]	5.192 204	E+02
Britsh thermal unitth inch per second square foot degree Fahrenheit [Btuth · in/(s · ft2 · °F)]	watt per meter kelvin [W/(m · K)]	5.188 732	E+02
calorieth per centimeter second degree Celsius [calth/(cm · s · °C)]	watt per meter kelvin [W/(m · K)]	4.184	E+02

Thermal Diffusivity
To convert from	to	Multiply by
square foot per hour (ft2/h)	square meter per second (m2/s)	2.580 64	E-05
Thermal Insulance
To convert from	to	Multiply by
clo	square meter kelvin per watt (m2 · K/W)	1.55	E-01
degree Fahrenheit hour square foot per British thermal unitIT (°F · h · ft2/BtuIT)	square meter kelvin per watt (m2 · K/W)	1.761 102	E-01
degree Fahrenheit hour square foot per British thermal unitth (°F · h · ft2/Btuth)	square meter kelvin per watt (m2 · K/W)	1.762 280	E-01

Thermal Resistance
To convert from	to	Multiply by
degree Fahrenheit hour per British thermal unitIT (°F · h/BtuIT)	kelvin per watt (K/W)	1.895 634	E+00
degree Fahrenheit hour per British thermal unitth (°F · h/Btuth)	kelvin per watt (K/W)	1.896 903	E+00
degree Fahrenheit second per British thermal unitIT (°F · s/BtuIT)	kelvin per watt (K/W)	5.265 651	E-04
degree Fahrenheit second per British thermal unitth (°F · s/Btuth)	kelvin per watt (K/W)	5.269 175	E-04

Thermal Resistivity
To convert from	to	Multiply by
degree Fahrenheit hour square foot per British thermal unitIT inch [°F · h · ft2/(BtuIT · in)]	meter kelvin per watt (m · K/W)	6.933 472	E+00
degree Fahrenheit hour square foot per British thermal unitth inch [°F · h · ft2/(Btuth · in)]	meter kelvin per watt (m · K/W)	6.938 112	E+04

LENGTH
To convert from	to	Multiply by
ångström(Å)	meter (m)	1.0	E-10
ångström(Å)	nanometer (nm)	1.0	E-01
astronomical unit (AU)	meter (m)	1.495 979	E+11
chain (based on U.S. survey foot) (ch) 9	meter (m)	2.011 684	E+01
fathom (based on U.S. survey foot) 9	meter (m)	1.828 804	E+00
fermi	meter (m)	1.0	E-15
fermi	femtometer (fm)	1.0	E+00
foot (ft)	meter (m)	3.048	E-01
foot (U.S. survey) (ft) 9	meter (m)	3.048 006	E-01
inch (in)	meter (m)	2.54	E-02
inch (in)	centimeter (cm)	2.54	E+00
kayser(K)	reciprocal meter (m-1)	1	E+02
light year (l. y.) 19	meter (m)	9.460 73	E+15
microinch	meter (m)	2.54	E-08
microinch	micrometer (µm)	2.54	E-02
micron (µ)	meter (m)	1.0	E-06
micron (µ)	micrometer (µm)	1.0	E+00
mil (0.001 in)	meter (m)	2.54	E-05
mil (0.001 in)	millimeter (mm)	2.54	E-02
mile (mi)	meter (m)	1.609 344	E+03
mile (mi)	kilometer (km)	1.609 344	E+00
mile (based on U.S. survey foot) (mi) 9	meter (m)	1.609 347	E+03
mile (based on U.S. survey foot) (mi) 9	kilometer (km)	1.609 347	E+00
mile, nautical 21	meter (m)	1.852	E+03
parsec (pc)	meter (m)	3.085 678	E+16
pica (computer) (1/6 in)	meter (m)	4.233 333	E-03
pica (computer) (1/6 in)	millimeter (mm)	4.233 333	E+00
pica (printer's)	meter (m)	4.217 518	E-03
pica (printer's)	millimeter (mm)	4.217 518	E+00
point (computer) (1/72 in)	meter (m)	3.527 778	E-04
point (computer) (1/72 in)	millimeter (mm)	3.527 778	E-01
point (printer's)	meter (m)	3.514 598	E-04
point (printer's)	millimeter (mm)	3.514 598	E-01
rod (based on U.S. survey foot) (rd) 9	meter (m)	5.029 210	E+00
yard (yd)	meter (m)	9.144	E-01

LIGHT
To convert from	to	Multiply by
candela per square inch (cd/in2)	candela per square meter (cd/m2)	1.550 003	E+03
footcandle	lux (lx)	1.076 391	E+01
footlambert	candela per square meter (cd/m2)	3.426 259	E+00
lambert 18	candela per square meter (cd/m2)	3.183 099	E+03
lumen per square foot (lm/ft2)	lux (lx)	1.076 391	E+01
phot (ph)	lux (lx)	1.0	E+04
stilb (sb)	candela per square meter (cd/m2)	1.0	E+04

MASS and MOMENT OF INERTIA
To convert from	to	Multiply by
carat, metric	kilogram (kg)	2.0	E-04
carat, metric	gram (g)	2.0	E-01
grain (gr)	kilogram (kg)	6.479 891	E-05
grain (gr)	milligram (mg)	6.479 891	E+01
hundredweight (long, 112 lb)	kilogram (kg)	5.080 235	E+01
hundredweight (short, 100 lb)	kilogram (kg)	4.535 924	E+01
kilogram-force second squared per meter (kgf · s2/m)	kilogram (kg)	9.806 65	E+00
ounce (avoirdupois) (oz)	kilogram (kg)	2.834 952	E-02
ounce (avoirdupois) (oz)	gram (g)	2.834 952	E+01
ounce (troy or apothecary) (oz)	kilogram (kg)	3.110 348	E-02
ounce (troy or apothecary) (oz)	gram (g)	3.110 348	E+01
pennyweight (dwt)	kilogram (kg)	1.555 174	E-03
pennyweight (dwt)	gram (g)	1.555 174	E+00
pound (avoirdupois) (lb) 23	kilogram (kg)	4.535 924	E-01
pound (troy or apothecary) (lb)	kilogram (kg)	3.732 417	E-01
pound foot squared (lb · ft2)	kilogram meter squared (kg · m2)	4.214 011	E-02
pound inch squared (lb · in2)	kilogram meter squared (kg · m2)	2.926 397	E-04
slug (slug)	kilogram (kg)	1.459 390	E+01
ton, assay (AT)	kilogram (kg)	2.916 667	E-02
ton, assay (AT)	gram (g)	2.916 667	E+01
ton, long (2240 lb)	kilogram (kg)	1.016 047	E+03
ton, metric (t)	kilogram (kg)	1.0	E+03
tonne (called "metric ton" in U.S.) (t)	kilogram (kg)	1.0	E+03
ton, short (2000 lb)	kilogram (kg)	9.071 847	E+02
MASS DENSITY (see MASS DIVIDED BY VOLUME)

MASS DIVIDED BY AREA
To convert from	to	Multiply by
ounce (avoirdupois) per square foot (oz/ft2)	kilogram per square meter (kg/m2)	3.051 517	E-01
ounce (avoirdupois) per square inch (oz/in2)	kilogram per square meter (kg/m2)	4.394 185	E+01
ounce (avoirdupois) per square yard (oz/yd2)	kilogram per square meter (kg/m2)	3.390 575	E-02
pound per square foot (lb/ft2)	kilogram per square meter (kg/m2)	4.882 428	E+00
pound per square inch (not pound force) (lb/in2)	kilogram per square meter (kg/m2)	7.030 696	E+02
MASS DIVIDED BY CAPACITY (see MASS DIVIDED BY VOLUME)

MASS DIVIDED BY LENGTH
To convert from	to	Multiply by
denier	kilogram per meter (kg/m)	1.111 111	E-07
denier	gram per meter (g/m)	1.111 111	E-04
pound per foot (lb/ft)	kilogram per meter (kg/m)	1.488 164	E+00
pound per inch (lb/in)	kilogram per meter (kg/m)	1.785 797	E+01
pound per yard(lb/yd)	kilogram per meter (kg/m)	4.960 546	E-01
tex	kilogram per meter (kg/m)	1.0	E-06

MASS DIVIDED BY TIME (includes FLOW)
To convert from	to	Multiply by
pound per hour (lb/h)	kilogram per second (kg/s)	1.259 979	E-04
pound per minute (lb/min)	kilogram per second (kg/s)	7.559 873	E-03
pound per second (lb/s)	kilogram per second (kg/s)	4.535 924	E-01
ton, short, per hour	kilogram per second (kg/s)	2.519 958	E-01

MASS DIVIDED BY VOLUME (includes MASS DENSITY and MASS CONCENTRATION)
To convert from	to	Multiply by
grain per gallon (U.S.) (gr/gal)	kilogram per cubic meter (kg/m3)	1.711 806	E-02
grain per gallon (U.S.) (gr/gal)	milligram per liter (mg/L)	1.711 806	E+01
gram per cubic centimeter (g/cm3)	kilogram per cubic meter (kg/m3)	1.0	E+03
ounce (avoirdupois) per cubic inch (oz/in3)	kilogram per cubic meter (kg/m3)	1.729 994	E+03
ounce (avoirdupois) per gallon [Canadian and U.K. (Imperial)] (oz/gal)	kilogram per cubic meter (kg/m3)	6.236 023	E+00
ounce (avoirdupois) per gallon [Canadian and U.K. (Imperial)] (oz/gal)	gram per liter (g/L)	6.236 023	E+00
ounce (avoirdupois) per gallon (U.S.) (oz/gal)	kilogram per cubic meter (kg/m3)	7.489 152	E+00
ounce (avoirdupois) per gallon (U.S.) (oz/gal)	gram per liter (g/L)	7.489 152	E+00
pound per cubic foot (lb/ft3)	kilogram per cubic meter (kg/m3)	1.601 846	E+01
pound per cubic inch (lb/in3)	kilogram per cubic meter (kg/m3)	2.767 990	E+04
pound per cubic yard (lb/yd3)	kilogram per cubic meter (kg/m3)	5.932 764	E-01
pound per gallon [Canadian and U.K. (Imperial)] (lb/gal)	kilogram per cubic meter (kg/m3)	9.977 637	E+01
pound per gallon [Canadian and U.K. (Imperial)] (lb/gal)	kilogram per liter (kg/L)	9.977 637	E-02
pound per gallon (U.S.) (lb/gal)	kilogram per cubic meter (kg/m3)	1.198 264	E+02
pound per gallon (U.S.) (lb/gal)	kilogram per liter (kg/L)	1.198 264	E-01
slug per cubic foot (slug/ft3)	kilogram per cubic meter (kg/m3)	5.153 788	E+02
ton, long, per cubic yard	kilogram per cubic meter (kg/m3)	1.328 939	E+03
ton, short, per cubic yard	kilogram per cubic meter (kg/m3)	1.186 553	E+03

MOMENT OF FORCE or TORQUE
To convert from	to	Multiply by
dyne centimeter (dyn · cm)	newton meter (N · m)	1.0	E-07
kilogram-force meter (kgf · m)	newton meter (N · m)	9.806 65	E+00
ounce (avoirdupois)-force inch (ozf · in)	newton meter (N · m)	7.061 552	E-03
ounce (avoirdupois)-force inch (ozf · in)	millinewton meter (mN · m)	7.061 552	E+00
pound-force foot (lbf · ft)	newton meter (N · m)	1.355 818	E+00
pound-force inch (lbf · in)	newton meter (N · m)	1.129 848	E-01

MOMENT OF FORCE or TORQUE, DIVIDED BY LENGTH
To convert from	to	Multiply by
pound-force foot per inch (lbf · ft/in)	newton meter per meter (N · m/m)	5.337 866	E+01
pound-force inch per inch (lbf · in/in)	newton meter per meter (N · m/m)	4.448 222	E+00

PERMEABILITY
To convert from	to	Multiply by
darcy 15	meter squared (m2)	9.869 233	E-13
perm (0 °C)	kilogram per pascal second square meter [kg/(Pa · s · m2)]	5.721 35	E-11
perm (23 °C)	kilogram per pascal second square meter [kg/(Pa · s · m2)]	5.745 25	E-11
perm inch (0 °C)	kilogram per pascal second meter [kg/(Pa · s · m)]	1.453 22	E-12
perm inch (23 °C)	kilogram per pascal second meter [kg/(Pa · s · m)]	1.459 29	E-12

POWER
To convert from	to	Multiply by
erg per second (erg/s)	watt (W)	1.0	E-07
foot pound-force per hour (ft · lbf/h)	watt (W)	3.766 161	E-04
foot pound-force per minute (ft · lbf/min)	watt (W)	2.259 697	E-02
foot pound-force per second (ft · lbf/s)	watt (W)	1.355 818	E+00
horsepower (550 ft · lbf/s)	watt (W)	7.456 999	E+02
horsepower (boiler)	watt (W)	9.809 50	E+03
horsepower (electric)	watt (W)	7.46	E+02
horsepower (metric)	watt (W)	7.354 988	E+02
horsepower (U.K.)	watt (W)	7.4570	E+02
horsepower (water)	watt (W)	7.460 43	E+02

PRESSURE or STRESS (FORCE DIVIDED BY AREA)
To convert from	to	Multiply by
atmosphere, standard (atm)	pascal (Pa)	1.013 25	E+05
atmosphere, standard (atm)	kilopascal (kPa)	1.013 25	E+02
atmosphere, technical (at) 10	pascal (Pa)	9.806 65	E+04
atmosphere, technical (at) 10	kilopascal (kPa)	9.806 65	E+01
bar (bar)	pascal (Pa)	1.0	E+05
bar (bar)	kilopascal (kPa)	1.0	E+02
centimeter of mercury (0 °C) 13	pascal (Pa)	1.333 22	E+03
centimeter of mercury (0 °C) 13	kilopascal (kPa)	1.333 22	E+00
centimeter of mercury, conventional (cmHg) 13	pascal (Pa)	1.333 224	E+03
centimeter of mercury, conventional (cmHg) 13	kilopascal (kPa)	1.333 224	E+00
centimeter of water (4 °C) 13	pascal (Pa)	9.806 38	E+01
centimeter of water, conventional (cmH2O) 13	pascal (Pa)	9.806 65	E+01
dyne per square centimeter (dyn/cm2)	pascal (Pa)	1.0	E-01
foot of mercury, conventional (ftHg) 13	pascal (Pa)	4.063 666	E+04
foot of mercury, conventional (ftHg) 13	kilopascal (kPa)	4.063 666	E+01
foot of water (39.2 °F) 13	pascal (Pa)	2.988 98	E+03
foot of water (39.2 °F) 13	kilopascal (kPa)	2.988 98	E+00
foot of water, conventional (ftH2O) 13	pascal (Pa)	2.989 067	E+03
foot of water, conventional (ftH2O) 13	kilopascal (kPa)	2.989 067	E+00
gram-force per square centimeter (gf/cm2)	pascal (Pa)	9.806 65	E+01
inch of mercury (32 °F) 13	pascal (Pa)	3.386 38	E+03
inch of mercury (32 °F) 13	kilopascal (kPa)	3.386 38	E+00
inch of mercury (60 °F) 13	pascal (Pa)	3.376 85	E+03
inch of mercury (60 °F) 13	kilopascal (kPa)	3.376 85	E+00
inch of mercury, conventional (inHg) 13	pascal (Pa)	3.386 389	E+03
inch of mercury, conventional (inHg) 13	kilopascal (kPa)	3.386 389	E+00
inch of water (39.2 °F) 13	pascal (Pa)	2.490 82	E+02
inch of water (60 °F) 13	pascal (Pa)	2.4884	E+02
inch of water, conventional (inH2O) 13	pascal (Pa)	2.490 889	E+02
kilogram-force per square centimeter (kgf/cm2)	pascal (Pa)	9.806 65	E+04
kilogram-force per square centimeter (kgf/cm2)	kilopascal (kPa)	9.806 65	E+01
kilogram-force per square meter (kgf/m2)	pascal (Pa)	9.806 65	E+00
kilogram-force per square millimeter (kgf/mm2)	pascal (Pa)	9.806 65	E+06
kilogram-force per square millimeter (kgf/mm2)	megapascal (MPa)	9.806 65	E+00
kip per square inch (ksi) (kip/in2)	pascal (Pa)	6.894 757	E+06
kip per square inch (ksi) (kip/in2)	kilopascal (kPa)	6.894 757	E+03
millibar (mbar)	pascal (Pa)	1.0	E+02
millibar (mbar)	kilopascal (kPa)	1.0	E-01
millimeter of mercury, conventional (mmHg) 13	pascal (Pa)	1.333 224	E+02
millimeter of water, conventional (mmH2O) 13	pascal (Pa)	9.806 65	E+00
poundal per square foot	pascal (Pa)	1.488 164	E+00
pound-force per square foot (lbf/ft2)	pascal (Pa)	4.788 026	E+01
pound-force per square inch (psi) (lbf/in2)	pascal (Pa)	6.894 757	E+03
pound-force per square inch (psi) (lbf/in2)	kilopascal (kPa)	6.894 757	E+00
psi (pound-force per square inch) (lbf/in2)	pascal (Pa)	6.894 757	E+03
psi (pound-force per square inch) (lbf/in2)	kilopascal (kPa)	6.894 757	E+00
torr (Torr)	pascal (Pa)	1.333 224	E+02

RADIOLOGY
To convert from	to	Multiply by
curie (Ci)	becquerel (Bq)	3.7	E+10
rad (absorbed dose) (rad)	gray (Gy)	1.0	E-02
rem (rem)	sievert (Sv)	1.0	E-02
roentgen (R)	coulomb per kilogram (C/kg)	2.58	E-04
SPEED (see VELOCITY)
STRESS (see PRESSURE)

TEMPERATURE
To convert from	to	Multiply by
degree Celsius (°C)	kelvin (K)	T/K = t/°C + 273.15
degree centigrade 16	degree Celsius (°C)	t/°C ≈ t/deg. cent.
degree Fahrenheit (°F)	degree Celsius (°C)	t/°C = (t/°F - 32)/1.8
degree Fahrenheit (°F)	kelvin (K)	T/K = (t/°F + 459.67)/1.8
degree Rankine (°R)	kelvin (K)	T/K = (T/°R)/1.8
kelvin (K)	degree Celsius (°C)	t/°C = T/K - 273.15

TEMPERATURE INTERVAL
To convert from	to	Multiply by
degree Celsius (°C)	kelvin (K)	1.0	E+00
degree centigrade 16	degree Celsius (°C)	1.0	E+00
degree Fahrenheit (°F)	degree Celsius (°C)	5.555 556	E-01
degree Fahrenheit (°F)	kelvin (K)	5.555 556	E-01
degree Rankine (°R)	kelvin (K)	5.555 556	E-01

TIME
To convert from	to	Multiply by
day (d)	second (s)	8.64	E+04
day (sidereal)	second (s)	8.616 409	E+04
hour (h)	second (s)	3.6	E+03
hour (sidereal)	second (s)	3.590 170	E+03
minute (min)	second (s)	6.0	E+01
minute (sidereal)	second (s)	5.983 617	E+01
second (sidereal)	second (s)	9.972 696	E-01
shake	second (s)	1.0	E-08
shake	nanosecond (ns)	1.0	E+01
year (365 days)	second (s)	3.1536	E+07
year (sidereal)	second (s)	3.155 815	E+07
year (tropical)	second (s)	3.155 693	E+07
TORQUE (see MOMENT OF FORCE)

VELOCITY (includes SPEED)
To convert from	to	Multiply by
foot per hour (ft/h)	meter per second (m/s)	8.466 667	E-05
foot per minute (ft/min)	meter per second (m/s)	5.08	E-03
foot per second (ft/s)	meter per second (m/s)	3.048	E-01
inch per second (in/s)	meter per second (m/s)	2.54	E-02
kilometer per hour (km/h)	meter per second (m/s)	2.777 778	E-01
knot (nautical mile per hour)	meter per second (m/s)	5.144 444	E-01
mile per hour (mi/h)	meter per second (m/s)	4.4704	E-01
mile per hour (mi/h)	kilometer per hour (km/h)	1.609 344	E+00
mile per minute (mi/min)	meter per second (m/s)	2.682 24	E+01
mile per second (mi/s)	meter per second (m/s)	1.609 344	E+03
revolution per minute (rpm) (r/min)	radian per second (rad/s)	1.047 198	E-01
rpm (revolution per minute) (r/min)	radian per second (rad/s)	1.047 198	E-01

VISCOSITY, DYNAMIC
To convert from	to	Multiply by
centipoise (cP)	pascal second (Pa · s)	1.0	E-03
poise (P)	pascal second (Pa · s)	1.0	E-01
poundal second per square foot	pascal second (Pa · s)	1.488 164	E+00
pound-force second per square foot (lbf · s/ft2)	pascal second (Pa · s)	4.788 026	E+01
pound-force second per square inch (lbf · s/in2)	pascal second (Pa · s)	6.894 757	E+03
pound per foot hour [lb/(ft · h)]	pascal second (Pa · s)	4.133 789	E-04
pound per foot second [lb/(ft · s)]	pascal second (Pa · s)	1.488 164	E+00
rhe	reciprocal pascal second [(Pa · s)-1]	1.0	E+01
slug per foot second [slug/(ft · s)]	pascal second (Pa · s)	4.788 026	E+01

VISCOSITY, KINEMATIC
To convert from	to	Multiply by
centistokes (cSt)	meter squared per second (m2/s)	1.0	E-06
square foot per second (ft2/s)	meter squared per second (m2/s)	9.290 304	E-02
stokes (St)	meter squared per second (m2/s)	1.0	E-04

VOLUME (includes CAPACITY)
To convert from	to	Multiply by
acre-foot (based on U.S. survey foot) 9	cubic meter (m3)	1.233 489	E+03
barrel [for petroleum, 42 gallons (U.S.)](bbl)	cubic meter (m3)	1.589 873	E-01
barrel [for petroleum, 42 gallons (U.S.)](bbl)	liter (L)	1.589 873	E+02
bushel (U.S.) (bu)	cubic meter (m3)	3.523 907	E-02
bushel (U.S.) (bu)	liter (L)	3.523 907	E+01
cord (128 ft3)	cubic meter (m3)	3.624 556	E+00
cubic foot (ft3)	cubic meter (m3)	2.831 685	E-02
cubic inch (in3) 14	cubic meter (m3)	1.638 706	E-05
cubic mile (mi3)	cubic meter (m3)	4.168 182	E+09
cubic yard (yd3)	cubic meter (m3)	7.645 549	E-01
cup (U.S.)	cubic meter (m3)	2.365 882	E-04
cup (U.S.)	liter (L)	2.365 882	E-01
cup (U.S.)	milliliter (mL)	2.365 882	E+02
fluid ounce (U.S.) (fl oz)	cubic meter (m3)	2.957 353	E-05
fluid ounce (U.S.) (fl oz)	milliliter (mL)	2.957 353	E+01
gallon [Canadian and U.K. (Imperial)] (gal)	cubic meter (m3)	4.546 09	E-03
gallon [Canadian and U.K. (Imperial)] (gal)	liter (L)	4.546 09	E+00
gallon (U.S.) (gal)	cubic meter (m3)	3.785 412	E-03
gallon (U.S.) (gal)	liter (L)	3.785 412	E+00
gill [Canadian and U.K. (Imperial)] (gi)	cubic meter (m3)	1.420 653	E-04
gill [Canadian and U.K. (Imperial)] (gi)	liter (L)	1.420 653	E-01
gill (U.S.) (gi)	cubic meter (m3)	1.182 941	E-04
gill (U.S.) (gi)	liter (L)	1.182 941	E-01
liter (L) 20	cubic meter (m3)	1.0	E-03
ounce [Canadian and U.K. fluid (Imperial)] (fl oz)	cubic meter (m3)	2.841 306	E-05
ounce [Canadian and U.K. fluid (Imperial)] (fl oz)	milliliter (mL)	2.841 306	E+01
ounce (U.S. fluid) (fl oz)	cubic meter (m3)	2.957 353	E-05
ounce (U.S. fluid) (fl oz)	milliliter (mL)	2.957 353	E+01
peck (U.S.) (pk)	cubic meter (m3)	8.809 768	E-03
peck (U.S.) (pk)	liter (L)	8.809 768	E+00
pint (U.S. dry) (dry pt)	cubic meter (m3)	5.506 105	E-04
pint (U.S. dry) (dry pt)	liter (L)	5.506 105	E-01
pint (U.S. liquid) (liq pt)	cubic meter (m3)	4.731 765	E-04
pint (U.S. liquid) (liq pt)	liter (L)	4.731 765	E-01
quart (U.S. dry) (dry qt)	cubic meter (m3)	1.101 221	E-03
quart (U.S. dry) (dry qt)	liter (L)	1.101 221	E+00
quart (U.S. liquid) (liq qt)	cubic meter (m3)	9.463 529	E-04
quart (U.S. liquid) (liq qt)	liter (L)	9.463 529	E-01
stere (st)	cubic meter (m3)	1.0	E+00
tablespoon	cubic meter (m3)	1.478 676	E-05
tablespoon	milliliter (mL)	1.478 676	E+01
teaspoon	cubic meter (m3)	4.928 922	E-06
teaspoon	milliliter (mL)	4.928 922	E+00
ton, register	cubic meter (m3)	2.831 685	E+00

VOLUME DIVIDED BY TIME (includes FLOW)
To convert from	to	Multiply by
cubic foot per minute (ft3/min)	cubic meter per second (m3/s)	4.719 474	E-04
cubic foot per minute (ft3/min)	liter per second (L/s)	4.719 474	E-01
cubic foot per second (ft3/s)	cubic meter per second (m3/s)	2.831 685	E-02
cubic inch per minute (in3/min)	cubic meter per second (m3/s)	2.731 177	E-07
cubic yard per minute (yd3/min)	cubic meter per second (m3/s)	1.274 258	E-02
gallon (U.S.) per day (gal/d)	cubic meter per second (m3/s)	4.381 264	E-08
gallon (U.S.) per day (gal/d)	liter per second (L/s)	4.381 264	E-05
gallon (U.S.) per minute (gpm) (gal/min)	cubic meter per second (m3/s)	6.309 020	E-05
gallon (U.S.) per minute (gpm) (gal/min)	liter per second (L/s)	6.309 020	E-02
WORK (see ENERGY)

---