Fuji Electric FRENIC-Ace series - Appendix E Conversion from si Units

Appendix E Conversion from SI Units
Appendix-22
Appendix E Conversion from SI Units
All expressions given in Chapter 10 “SELECTING OPTIMAL MOTOR AND INVERTER CAPACITIES” are based
on SI units (The International System of Units). This section explains how to convert expressions to other units.
E.1 Conversion of units
(1) Force
• 1 [kgf] ≈ 9.8 [N]
• 1 [N] ≈ 0.102 [kgf]
(2) Torque
• 1 [kgf•m] ≈ 9.8 [N•m]
• 1 [N•m] ≈ 0.102 [kgf•m]
(3) Power (energy)
• 1 [kgf•m] ≈ 9.8 [N•m] = 9.8 [J] = 9.8 [W•s]
(4) Power
• 1 [kgf•m/s] ≈ 9.8 [N•m/s] = 9.8 [J/s] = 9.8 [W]
• 1 [N•m/s] ≈ 1 [J/s] = 1 [W] ≈ 0.102 [kgf•m/s]
(5) Rotation speed
•
]s/rad[1047.0]s/rad[
60
2
][min1
1-
≈
π
=
•
][min549.9][min
2
60
]s/rad[1
11 −−
≈
π
=
(6) Inertia constant
J [kg•m
2
] : moment of inertia
GD2 [kg•m
2
] : flywheel effect
• GD
2
= 4J
•
4
GD
J
2
=
(7) Pressure, stress
• 1 [mmAq] ≈ 9.8 [Pa] ≈9.8 [N/m
2
]
• 1 [Pa] ≈ 1 [N/m2] ≈ 0.102 [mmAq]
• 1 [bar] ≈ 100000 [Pa] ≈ 1.02 [kg•cm2]
• 1 [kg•cm
2
] ≈ 98000 [Pa] ≈ 980 [mbar]
• 1 barometric pressure
= 1013 [mbar] = 760 [mmHg]
= 101300 [Pa] ≈ 1.033 [kg/cm
2
]