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Which is the working voltage range of an RCD? According to the product standards for RCDs, these devices have to be equipped with a test device to simulate the passing through the detecting device of a residual current in order to allow a periodic testing of the ability of the residual current device to operate. The operating voltage of the test button identifies the working voltage of the RCD: Ut range is the real operating range of an RCD because the device has to be installed in way it&rsqu …

Main contactor Q: Is there any requirement to put a main contactor in series before the softstarter? A: The softstarter does not require any main contactor but we recommend the use of one for emergency stop and/or trip of the overload relay. In some applications an MCCB can be used instead of the main contactor. Ambient temperature Q: Can I use a softstarter if the ambient temperature is higher than the recommended value during operation? A: The softstarter can normally be operated at a …

Q: What technical changes were done on Manual Motor Starters (MMS) and contactors to fulfil IE3 standards? A: To be able to start premium efficiency motors (IE3-motors) we have increased the magnetic tripping level for some MMS to secure a start without tripping. The implementation became effective in August 2014. The modern AF contactors from ABB have already from the beginning been designed to handle high efficiency motors. When designing contactors to match the new efficient motors it is a …

Q: Can a GFCI circuit breaker be installed on the AC power feeding a drive, or will the drive cause it to trip? A: The AC Drive most likely will cause the GFCI protection device to trip. The reason the AC Drive will cause this tripping of the GFCI is the Common Mode Current or Common Mode Noise (CM Noise) that the VFD is producing. The high rate that the IGBT is switched on and off is around (1 - 16 kHz). This switching creates Common Mode Electrical Noise. The Common Mode Noise is the current …

Q: What is the temperature rating on the EMAX circuit  breaker? A: The base rating on all EMAX circuit breakers is 40 degrees Celsius. However, they can  operate at higher temperatures in certain installation conditions, breaker types and frame sizes. For example, the EMAX E1, 800 A frame breaker can operate under full load up to 70 degrees Celsius. The EMAX E3, 1600 A frame breaker can also operate under full load up to 70 degrees Celsius. Charts are available for selecting the right …