Bonfiglioli BN-BE-BX Series Motor Selection Guide

3. Independent forced air cooling (U1/U2)

When the motor operates in the low-frequency range below 30Hz for a long time, the cooling effect of the built-in fan (IC411) drops sharply. At this point, it is necessary to select a forced air cooling system with independent power supply (U1 or U2 options). On page 47 of the manual, it is stated that U1 separates the fan junction box from the motor main junction box, while U2 introduces the fan power cord into the main junction box. For motors with brakes, after selecting U1, the default orientation AA of the brake release lever will not be available (this limitation is clearly stated on page 48 of the manual).

Quick Search for Global Market Certification Options

The BN-BE-BX series covers compliance certifications for major global markets (pages 22-27 of the manual), which is of great significance for export equipment manufacturers in terms of selection:

CUS (North America): UL/CSA certification, applicable to the United States and Canada. Please note that certain specifications of BX 100 are only available in the US market and are not applicable to Canada (page 24 of the manual).

CCC (China): Compulsory certification in China, applicable to specific power ranges of BN/M series.

CEL (China Energy Efficiency Label): For BX motors with a power output of ≥ 0.75kW, they must comply with the GB18613-2012 standard.

BIS (India): Certified by the Bureau of Indian Standards, covering BE/BX series ≤ 7.5kW.

EECA (Australia/New Zealand): Registration is required in the Energyrating database.

When selecting, the corresponding certification code must be clearly specified in the model based on the final export destination of the equipment.

Selection and Avoidance Guide

Neglecting the engineering margin of "locked rotor current and starting torque":

The BX-IE3 60Hz data sheet on page 62 of the manual shows the locked rotor current of BX90S 4P（Is/In）8.2, starting torque（Ms/Mn）For 4.1. If the capacity of the power transformer is insufficient (with a large voltage drop) or the static friction coefficient of the load is high, it may lead to startup failure. When selecting, it is necessary to verify the wiring capacity and rated current of the contactor.

Brake selection only depends on torque:

As mentioned earlier, braking power (Wmax) and response time (t ₂) are equally lethal. If the distance of the crane hook slip exceeds the standard, it is often not due to insufficient braking torque, but due to improper selection of rectifiers causing delayed braking response. At this point, an SBR rectifier must be selected and equipped with an independent DC power supply (SD option).

Misunderstanding the power mapping between "S1 working system" and "S3 working system":

The power amplification factors for S2 (short-term operation) and S3 (intermittent periodic operation) are provided on page 28 of the manual（fm）. If the equipment is actually operated under S3-40% intermittent working mode, but selected according to S1 continuous working mode, it will result in overly conservative motor selection and cost waste. Should utilize S3

fm=one point one five

f m=Reasonable selection of amplification factor of 1.15.

Vertical installation without considering bearing lubrication:

When installed vertically, the lubricating oil of standard bearings may not be effectively distributed. In the bearing table on page 19 of the manual, some large machine bases (such as BX 200K and above) have been marked with "Reguassable bearings with M6x1 Greasing Device", which need to be included in the regular grease injection maintenance plan after selection.