CEMP AAB30/AAC30 Aluminium Frame 56 Ex db Motors

Small aluminium frame 56 Ex db motors for fans and small pumps

The CEMP AAB30/AAC30 aluminium frame 56 motors are small three-phase, 60 W to 120 W flameproof motors used mainly for fixed and portable fan applications, and also for small pumps and other duties that call for ATEX and IECEx certification. Several mounting types are possible in the same enclosure, and the terminal box sits at the non-drive end, giving a slim shape for tight spaces. The brochure explains that aluminium offers high resistance to corrosion and atmospheric attack, except in some harsh environments such as sulfuric acid, and is about one third the weight of cast iron.

Technical specifications

Fit and application notes

At 60 to 120 W these motors serve special applications that need very low power or a small footprint. Because they are not ventilated (IC410), duty and ambient temperature must be checked against the temperature class. The dust marking and surface temperature depend on the Ex tb construction, and the gas group IIB or IIC limits the maximum ambient (60 C for IIC, 80 C for IIB). Mounting flexibility lets one motor type serve foot, flange or pad mounting. The brochure also highlights a stainless steel nameplate, a multi-voltage nameplate and PTC protection for inverter use, with certifications available on request. For larger power or other frame sizes, the E3A/E4A flameproof series in the same brochure starts at frame 80, so the frame and kW should be fixed first.

Ordering information

The brochure is a series summary, not an ordering code table, so the exact designation, mounting, voltage and certificate version must be confirmed with the manufacturer. State the rated power, poles, voltage, frequency, mounting, ambient, group and temperature class, and note that certifications are available on request.

Typical applications in hazardous areas

These frame 56 flameproof motors are intended for low-power drives inside classified areas. The brochure names fixed and portable fan applications and small pumps, and in practice this covers ventilation of analyser shelters and small enclosures, portable ventilation used during maintenance in hazardous zones, small transfer and dosing pumps, and other compact auxiliary equipment in refineries, gas plants, chemical facilities, fuel depots and dusty process areas covered by the dust markings in the table.

The slim shape with the terminal box at the non-drive end helps where a motor must fit inside equipment or close to other components, which is common on skid-mounted packages and portable units.

Selection for the hazardous area

Start from the area classification. Confirm whether the location is gas, dust or both, then select the group and temperature class required by the area classification drawing. Gas group IIC covers the most demanding gases but carries the lower maximum ambient stated in the table, while IIB allows a higher ambient. For dust areas, compare the maximum surface temperature of the motor with the ignition temperature of the dust present. Because the motor is not ventilated, check the duty cycle and the ambient together, especially where the motor runs continuously.

Where the motor will be fed from an inverter, the PTC option listed in the brochure should be part of the order discussion, and the inverter and motor combination should be reviewed against the certificate conditions.

Installation practice

Installation in hazardous areas must follow the certificate conditions and the applicable installation rules for the site. Make the electrical connection in line with the certificate and the protection concept, keep flameproof joints clean and undamaged, and do not modify the enclosure. Check that the nameplate marking matches the area requirements before installation. Choose the mounting type that matches the driven equipment so that the motor is supported correctly and alignment is maintained.

After installation, record the motor marking, area classification and inspection results in the hazardous-area register for the site. Periodic inspection should check the condition of the enclosure, the terminal box cover and the mounting, and any repair to a flameproof motor should be carried out in line with the certificate and the applicable repair rules rather than by improvised methods on site. Keeping the brochure and certificate details with the motor records helps maintenance staff confirm that a replacement motor carries the same marking, group, temperature class and mounting as the original.

Site conditions in Oman and the GCC

Oil, gas and petrochemical facilities in Oman often combine hazardous-area classification with high ambient temperatures, so the ambient limits in the table must be compared with the hottest expected conditions at the motor location, including direct sun. The brochure notes the good corrosion resistance of aluminium, but it also names harsh environments where this does not hold, so the actual chemical exposure at the site should be checked. Dust and sand favour the higher protection degree in the table for outdoor and desert installations.

Documents and quotation

Provide the fan or pump load, power, poles, voltage, mounting form, zone and temperature class. The brochure states that the values may change without prior notice and are reference values.

The manufacturer document is attached to this page and listed below. Seven Star LLC is an independent supplier in Muscat and can quote against the model code, quantity and delivery location. Browse more instruments in Electric Motors, or see the CEMP brand page.