Fuji Electric Frenic-Mini - App. E Conversion from SI Units

App.E Conversion from SI Units
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App.
App. E Conversion from SI Units
All expressions given in Chapter 7, "SELECTING OPTIMAL MOTOR AND INVERTER
CAPACITIES" are based on SI units (International Metric System of Units). This section explains
how to convert expressions to other units.
[ 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) Work and 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
•
(rad/s)0.1047)s/rad(
60
2
(r/min)1 ≈
π
=
•
(r/min)9.549(r/min)
2
60
)s/rad(1 ≈
π
=
(6) Inertia constant
J (kg·m
2
) :moment of inertia
GD
2
(kg·m
2
) :flywheel effect
• GD
2
= 4 J
•
4
GD
J
2
=
(7) Pressure and stress
• 1 (mmAq) ≈ 9.8 (Pa) ≈ 9.8 (N/m
2
)
• 1(Pa) ≈ 1(N/m
2
) ≈ 0.102 (mmAq)
• 1 (bar) ≈ 100000 (Pa) ≈ 1.02 (kg·cm
2
)
• 1 (kg·cm
2
) ≈ 98000 (Pa) ≈ 980 (mbar)
• 1 atmospheric pressure = 1013 (mbar)
= 760 (mmHg) = 101300 (Pa)
≈ 1.033 (kg/cm
2
)
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