Frequency inverters, even from the same manufacturer, can be constructed and/or configured very differently. Using Icontrol and Fcontrol frequency inverters from the ZIEHL-ABEGG product range for example, shows why it´s essential to select the correct frequency inverter for the application under consideration.
Icontrol frequency inverter:
Icontrol is particularly designed for air conditioning applications. In most cases they control fans with IEC-Standard-Motors, connected one inverter to one motor using screened power cables. The integrated interference suppression filtration is in accordance with limit class B.
Special solutions have always been a strength of Ziehl-Abegg; Icontrol inverters are available with either IP20 and IP54 protection, as well as with special designs and enclosures. For extremely compact air handling units Icontrol is also available as a “flat” version which can be mounted in the interior of the air handling unit next to the fan with minimum space requirements. Icontrol flat is also IP54 rated.
Further benefits of Icontrol:
- integrated process control e.g. using differential pressure or air flow in ventilation technology
- simplified start-up using preset selectable operating modes
- integrated or external multifunction display with selectable languages
- a single source solution when used in combination with ZIEHL-ABEGG fans
- reasonably priced
Fcontrol frequency inverter: Fcontrol inverters are frequency inverters with integrated all-pole effective sinusoidal filtration, enabling “gentle” motor operation. This means that even motors which are not approved for operation with frequency inverters can be controlled by Fcontrol, and are protected from bearing currents and premature bearing wear. Also there is no danger to motor windings or insulation. For further and more detailed information we recommend European Standard DIN IEC/TS 60037-17, which is dedicated to the potential hazards exhibited by standard frequency inverters without sine filters.
Due to the sinusoidal shape of the Fcontrol´s output voltage and current, unlimited parallel operation of multiple motors is feasible without problems.
Further benefits of Fcontrol:
- integrated process control e.g. using temperature or pressure in refrigeration systems, differential pressure, airflow or air velocity in ventilation systems
- simplified start-up using preset selectable operating modes
- multifunction display with selectable languages
- no limitation on the motor cable length
- shielded motor cables are not necessary, therefore ideal for retrofits using existing power cables
- absence of electro-magnetic noise, therefore appropriate for noise-sensitive environments (clock frequencies 16kHz without performance reduction)
- interference suppression in accordance with limit class B even without shielded motor cables
- available in IP20 or IP54
Aside from fan speed control, frequency inverters are used increasingly for pump speed control. Another benefit of frequency inverters is the possibility of continuously variable, demand-dependent speed control. Generally speaking, frequency inverters are gaining in popularity, not least because of their superior energy efficiency compared with, for example, voltage-based motor speed control. Further information relating to energy savings by speed controllable drives can be found on VDI guideline 6014.
