MOTOVARIO
Information
Helical bevel geared motors
7
Information
The table below lists the nominal thermal power values expressed in kW, in the following reference conditions:
• mounting position B3
•
continuous operation at input speed <= 1800 rpm
• ambient temperature 77°F
• sea level altitude
•
air speed near the gear reducer >= 38ips
•
absence of external radial and/or axial loads
Applying a power level not exceeding Pth
- at the above-mentioned reference conditions - guarantees the correct lubrication and efficient operation of the gear reducer.
NOTE: For the BA series it is not necessary to check the thermal power.
Application check
Except for continuous operating times below two (2) hours and successive pauses capable of bringing the gear reducer back to ambient temperature, for each application it is advisable to
verify the gear reducer’s thermal limit according to the following formula:
Pm < Pth * Fc * Fv*Fa
.
where:
Pm = input power to the gear reducer at 1.400 rpm (4-pole motors)
Pth = thermal power at the reference conditions (see above table)
Fc = ambient and operating temperature correction factor
Fv = ventilation correction factor
Fa = altitude correction factor
The correction factors refer to different operating conditions compared to the reference conditions, and are provided by the following ISO14179 tables:
Thermal power Pth [HP]
Thermal power values at 1750 rpm
Gear reducer
Pth [HP]
B063
9
B083
10
B103
13
B123
20.5
B143
26
B153
41
B163
52