0-7 SI UNITS Meaning of SI This manual uses SI units. SI represents the International System of Units, which was established to unify the various systems of units used in the past for smoother international technical communication. New Units Adopted in SI * 1: X represents the value in SI units as converted from 1 [in conventional units], which can be used as the rate for conversion between conventional and SI units. * 2: In the past, kilogram [kg] representing mass was often used in place of weight kilogram [kgf], which should be used as the unit of force.
Conversion between Conventional and SI Units Equation for conversion When converting, change the unit of the value in conventional or SI units to the one in the conversion rate column in the table above before calculation. For example, when converting 100 W to the value in conventional unit PS, first change it to 0.1 kW and divide by the conversion rate 0.735499.
Item New unit Conventional unit Conversion rate*1 (1 [conventional unit] = X [SI unit]) Force*2 N (newton) kgf 1 kgf = 9.80665 N Torque*2 (Moment) N·m kgf·cm 1 kgf·cm = 9.80665 N·m Pressure*2 Pa (pascal) kgf/cm2 1 kgf/cm2 = 98.0665 kPa = 0.0980665 MPa ↑ ↑ mmHg 1 mmHg = 0.133322 kPa Revolving speed rpm rpm 1 rpm = 1 r/min Spring constant*2 N/mm kgf/mm 1 kgf/mm = 9.80665 N/mm Volume l cc 1 cc = 1 ml Power W PS system 1 PS = 0.735499 kW Heat quantity W·h cal 1 kcal = 1.16279 W·h Specific fuel consumption g/W·h g/PS·h 1 g/PS·h = 1.3596 g/kW·h Value in SI unit = Conversion rate × Value in conventional unit Conversion rate:
Figure corresponding to X in the conversion rate column in the table above Value in conventional unit = Value in SI unit ÷ Conversion rate