Technical Calculation of Power

Calculation for lifting unit drive

In the case of frequent start-stop operation, consider the load factor listed in a calalog.
Click here to refer the load factor listed in a catalog.

Summary of the machine

1.1 Specification of machine

① Gross weight of load side
W = kg
② Total weight of counter balance weight
C = kg
③ Total weight of wire rope or chain
Y = kg
④ Diameter of dram, or P.C.D of main sprocket wheel
D = mm

1.2. Connecting method with reducer (gearmotor)

 Using a sprocket wheel or a gear  Shaft direct connection

⑤ P.C.D of a sprocket wheel or a gear
P1 = mm
⑥ P.C.D of a sprocket wheel or a gear
P2 = mm

Decision of any condition for input & output

① Motor speed
N = r/min

Decision of conveyance speed and reduction ratio

 In the case that conveyance speed is decided  In the case that redcution ratio is decided

① Speed
V = m/min
② Reduction ratio (calculated value at ①)
Z =  
① Reduction ratio
Z =
② Speed(calculated value at ①)
V = m/min

Caluclation of lead torque

4.1 Input of efficiency

① Efficiency of reducer and gearmotor
ηc =  
② Efficiency of the sprocket wheel or the gear
ηg =  

4.2 Calculation result (load torque and motor power)

③ Caluclation of load torque
Tf = N･m
④ Conversion from load torque Tf to motor-power Pf
Pf = kW

Calculation of load moment of inertia

5.1 Calculation result (load moment of inertia)

① Moment of inertia of carrier and chain or belt (Converted in a motor shaft)
JW = kg･m2

5.2 Calculating the moment of inertia of total load

 Input mass of sprocket, drum, gear etc.  Weight of sprocket, drum, gear etc is unknown

② Total weight of sprocket wheel and gear (P1)
Wp1 = kg
③ Total weight of sprocket wheel and gear (P2)
Wp2 = kg
④ Moment of inertia of sprocket wheel or gear (Converted in a motor shaft)
 
 
Jp1 = kg･m2
 
Jp2 = kg･m2
② Moment of inertia of sprocket wheel or gear (Converted in a motor shaft)
Jp1+Jp2 = kg･m2
⑤ The moment of inertia of total load (Converted in a motor shaft)
Jf = kg･m2

Temporary selection of motor

6.1 Type of motor

 Standard type  For inverter drive

① Motor power
kW × P
② Brake
 
③ Pattern of operation
 
 

Pattern of operation

Commercial power supply
A = sec
 
B = sec
Inverter control
C = sec
 
D = sec
 
E = sec
 
B = sec