ABB RH35M-4EK.2F.1R Overview

ABB RH35M-4EK.2F.1R refers to a ZIEHL-ABEGG RH35M series centrifugal fan used in industrial
drive and electrical cabinet cooling applications. ABB documentation identifies RH35M-4EK.2F.1R
as an additional fan for cabinet installations where controlled airflow is required to maintain
suitable cooling conditions for drive modules. The product is therefore closely associated with
the thermal management of industrial power electronics rather than with motor control or power
conversion itself.

The RH35M-4EK.2F.1R designation is important when identifying the correct fan configuration.
ZIEHL-ABEGG is the fan manufacturer, while ABB documentation references the model for specific
drive cooling applications. This distinction is useful when creating equipment records, checking
installed components, or identifying the cooling fan associated with an ABB industrial drive
system.

Centrifugal fans are commonly used where air must be moved through an enclosure, filter system,
duct, or other airflow path against a defined pressure difference. In an industrial drive cabinet,
the fan contributes to the controlled removal of heat generated by power semiconductor devices,
control electronics, electrical connections, and other heat-producing components.

RH35M-4EK.2F.1R Fan Design

The RH35M-4EK.2F.1R belongs to the RH series of ZIEHL-ABEGG centrifugal fans. Its centrifugal
operating principle allows the fan to generate airflow suitable for applications where the air
path includes resistance from cabinet structures, filters, heat-generating assemblies, or other
ventilation components.

Unlike an axial fan, which primarily moves air along the direction of the rotating shaft, a
centrifugal fan draws air into the impeller and redirects it radially outward. This operating
principle makes centrifugal construction suitable for applications requiring airflow against
system pressure. The actual airflow achieved in an installation depends on the complete fan
system, including the inlet, outlet, filters, enclosure geometry, and pressure drop.

The RH35M-4EK.2F.1R therefore forms part of a larger ventilation arrangement. Correct operation
depends not only on the fan itself but also on the design of the cabinet airflow path. When used
with an industrial drive, the fan should be evaluated together with the enclosure dimensions,
ventilation openings, filters, and heat load of the installed equipment.

Application in ABB Drive Cooling

ABB technical documentation references RH35M-4EK.2F.1R as an additional fan for industrial drive
cabinet applications. In ABB documentation for ACQ810 drive modules, the RH35M-4EK.2F.1R from
ZIEHL-ABEGG is listed as an example of an additional fan for an IP54 cabinet. The documentation
specifies that the additional fan is used to support sufficient cooling of the drive module.

This application is particularly relevant to high-power drive installations because power
electronics generate heat during operation. Semiconductor switching devices, DC-link components,
contactors, reactors, control electronics, and other electrical assemblies all contribute to the
thermal load inside a cabinet. A suitable ventilation system helps move this heat away from the
equipment and maintain the required operating environment.

ABB documentation also describes a cabinet pressure-drop condition for the additional fan
application. This illustrates why fan selection cannot be based only on physical dimensions.
The fan must provide appropriate airflow under the pressure conditions created by filters,
cabinet construction, and other ventilation components.

ACS800 and Industrial Drive Cooling

The RH35M-4EK.2F.1R is also associated with ABB ACS800 drive cooling applications. ABB documentation
for industrial drive systems identifies RH35M-series fans in cabinet ventilation arrangements.
In an ACS800 installation, the cooling fan can form part of the thermal management system surrounding
the drive power section.

The thermal environment of a drive cabinet is influenced by several factors, including drive power,
ambient temperature, enclosure protection rating, air-filter condition, cabinet dimensions, and
the pressure drop through the ventilation path. The cooling fan works within this overall system
rather than operating as an independent thermal-control device.

For this reason, identifying the exact RH35M fan reference is useful when documenting an existing
drive installation. The complete model number should be retained because ZIEHL-ABEGG offers
multiple RH-series configurations with different electrical and mechanical characteristics.

Electrical Configuration

The RH35M-4EK.2F.1R is an electrically driven centrifugal fan designed for industrial ventilation
applications. Available technical references associate this model with a single-phase electrical
supply and an operating voltage around 230 V. The exact electrical characteristics should always
be checked against the fan nameplate and the applicable technical documentation for the specific
unit.

Fan selection requires consideration of the supply voltage, frequency, current, power consumption,
motor characteristics, and starting requirements. These parameters determine whether the fan can be
correctly integrated into the auxiliary power circuit of an industrial drive cabinet.

ABB drive documentation may also specify an associated capacitor or auxiliary component depending
on the particular cabinet and fan arrangement. The electrical connection should therefore follow
the wiring and installation requirements applicable to the specific drive cabinet rather than
relying solely on the general fan model designation.

Airflow and Thermal Management

Effective cooling depends on maintaining an appropriate airflow path through the cabinet. The fan
draws air through the designated inlet and moves it through the ventilation system so that heat
generated by the drive equipment can be transferred away from the electrical assemblies.

Filters are an important part of this process. As filter resistance increases, the pressure
requirement imposed on the fan also changes. ABB cabinet documentation therefore considers pressure
drop when specifying additional fan arrangements. A fan that is suitable in one enclosure design
may not provide the same airflow in another installation with different filters or ventilation
geometry.

Maintaining the intended airflow path is consequently an important part of drive thermal management.
Cabinet openings, filters, fan orientation, exhaust paths, and internal obstructions should all be
considered when assessing the cooling arrangement around the drive.

Product Identification

The complete reference RH35M-4EK.2F.1R should be used when identifying this fan. The RH35M series
includes multiple configurations, and similar model numbers may have different electrical or
mechanical characteristics. Recording the complete designation helps distinguish the required fan
from other RH-series products.

ABB documentation and drive component records may also contain ABB-specific component or spare-part
numbers associated with RH35M fan assemblies. In certain ACS800 documentation, RH35M-4EK.2F.1R is
referenced directly as a fan component, while other ABB documentation may identify a corresponding
component through an ABB ordering code. The applicable drive documentation should therefore be used
when matching the fan to a specific installation.

Maintenance Considerations

A cabinet cooling fan is an important part of the thermal system of an industrial drive. Fan
condition can influence airflow, cabinet temperature, and the thermal environment of the drive
power section. Maintenance procedures should consider the fan assembly, airflow path, filters,
electrical connections, and mechanical mounting.

When replacing or identifying an RH35M-4EK.2F.1R fan, the complete model designation should be
compared with the installed fan and the applicable ABB drive documentation. Electrical supply,
mounting arrangement, airflow direction, cabinet pressure conditions, and associated auxiliary
components should correspond with the intended application.

The fan should also be considered together with the cabinet ventilation design. Installing a fan
with a similar physical appearance but different electrical characteristics or airflow performance
may alter the intended cooling conditions. Technical identification should therefore be based on
the complete part number and system requirements.

Industrial Applications

RH35M-4EK.2F.1R centrifugal fans are relevant to industrial electrical enclosures where forced
ventilation is required. In ABB drive environments, the model is associated with cabinet cooling
arrangements for drive modules. Similar centrifugal fan principles are also applicable to control
cabinets, power electronics enclosures, automation equipment, and other systems where heat must be
removed through a controlled airflow path.

The use of a centrifugal design is particularly useful when the ventilation system includes
resistance from filters, ducts, or enclosure components. The fan’s ability to generate pressure
supports airflow through such systems, provided that the operating point remains within the
applicable fan performance range.

Conclusion

ABB RH35M-4EK.2F.1R is a ZIEHL-ABEGG RH35M series centrifugal fan referenced by ABB for industrial
drive and cabinet cooling applications. ABB documentation identifies the model as an additional fan
used to support adequate cooling of drive modules, particularly in cabinet ventilation arrangements.

The fan’s role is to provide controlled forced-air movement through the cabinet thermal-management
system. Its application depends on the complete ventilation design, including pressure drop, filters,
enclosure structure, airflow path, electrical supply, and heat load. For ACS800 and related ABB drive
installations, the complete RH35M-4EK.2F.1R designation should be used when identifying the fan and
comparing it with the applicable drive documentation.