RODIX Inc.
CE restrictions for harmonic current emissions
Revised 5/3/2006
For vibratory feeder controls that have the CE mark, one of the many standards that the control needs to conform to
is “Limits for harmonic current emission”. The machine configuration will determine when to apply this standard.
International Standard IEC 61000-3-2
Effective
1/1/2001
Limits – Limits for harmonic current emissions (equipment input current < 16A per phase)
This part of IEC 61000 deals with the limitation of harmonic currents injected into the public low-voltage
distribution system (electric utility). If the equipment input current exceeds 16A per phase, please refer to IEC
61000-3-4.
Harmonic currents can cause stress to the utility distribution system. It can stress the neutral of older wiring that
doesn’t conform to today’s standards, and it can stress the utility transformers that are operating at their rated load.
When the standard does not apply:
This standard doesn’t apply if the 230V machine is powered by a step down transformer.
The scope of the standard states:
IEC 61000-3-2 is applicable to electrical and electronic equipment having an input current up to and including 16A
per phase, and intended to be connected to public low-voltage distribution systems.
Public low-voltage distribution systems are power supply systems allowing the direct connection of equipment with
rated voltages between 200 and 260V (single phase) or between 340 and 450V (phase to phase). Higher voltage
distribution systems, which are connected to power substations, are not considered to be public low-voltage systems.
A 230V machine with a vibratory feeder is typically powered by a step down transformer that is installed in a
factory. Thus the machine is powered by a higher voltage distribution system that is not directly connected to the
230V public low-voltage system. Because of this, the machine is outside the scope of the standard
1
.
When the standard does apply:
When a 230V machine is not powered by a step down transformer, there should not be a problem meeting this
standard if all the vibratory feeders on one machine operate in the 100 Pulse (full wave) mode, and the combined
total amperage for the vibratory feeders is 15 Amps or less. However it is harder to meet this standard in the 50
Pulse (half wave) mode. The combined total amperage for the vibratory feeders is limited to 3.5 Amps in the 50
Pulse mode when the machine is powered directly from the 230V public low voltage distribution system.
The vendor that supplies the finished machine is responsible for compliance to the applicable CE standards, not the
end user. This vendor is responsible for performing the compliance testing on the finished machine.
Please note that EN61000-3-2 applies to 230V equipment. There are no limits for 120V equipment since these
limits have not yet been defined; however, in Europe the 120V equipment will be connected to a step down
transformer that might connect to the public 230V power mains. This means that 120V equipment that does not
meet the harmonic current standard may cause a step down transformer that connects to the public 230V to fail to
meet the harmonics standard.
50/100 Pulse – Alternate names:
The frequency of the utility power is 50Hz in Europe and 60Hz in the United States. Because of this, 50 Pulse mode
in Europe is related to 60 pulse mode in the United States. 100 Pulse mode in Europe is related to 120 pulse mode
in the United States. To change the pulse mode on the control, change the 60/120 switch. Listed below are some of
the alternate names used to describe 60 pulse and 120 pulse:
60 Pulses Per Sec.
120 Pulses Per Sec.
R.C. or D.C.
A.C.
Rectified
Full Wave AC
Direct Current
Alternating Current
Half Wave
Full Wave
3600 Vibrations Per Min.
7200 Vibrations Per Min.
1
From TUV Rheinland, FAQ
http://www.jpn.tuv.com/en/services/product_testing/all_types_of_products/electromagnetic_compatibility_services_emc_/emc_faq.php
© RODIX Inc. 2006
E:\Eng\CE\CE restrictions for harmonic current emissions 060501.doc
