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Dear all,
we have a customer designing and manufacturing Pulse Width Modulation power
controllers. These are used in the heating & ventilation industry , within
factories and hotels etc. due to the nature of the design switching full power
on and off between 2 and 30 times a minute it fails flicker EN61000-3-3.
Looking at the std and doing the maths on a 2kw load, it needs to be switching
only once a minute to meet flicker requirements. Problem with this is only
switching once a minute the control is lost !
My question is that PWM products obviously cannot meet the flicker std, but
what experience do other labs have of this. we found a micro from a co in
Sweden which sits in front of the mains input and affectively fools the
harmonics tester into, but this is both expensive and not really a solution.
What have other labs found, is there a solution, as flicker std only
addresses products up to 16A the high power controllers are ok, but they sell
many which run at 1.5kVA. Or do manf just 'ignore' the flicker requirements ?
any feedback would be much appreciated.
rgds,
Jules
Julian Jones Hursley EMC Services Brickfield Lane Chandlers Ford, EASTLEIGH Hampshire, SO53 4DP Tel: 023 8027 1111 Fax: 023 8027 1144 ju...@hursley-emc.co.uk www.hursley-emc.co.uk
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