Help me out here guys... I thought that conventional power supplies (transformer-bridge-filter) were relatively clean on reflected harmonics? Thanks, Matt KM5VI I found these fairly simple guidance n
Help me out here guys... I thought that conventional power supplies (transformer-bridge-filter) were relatively clean on reflected harmonics? No, the transformer is all inductive and the diodes cond
Nope! Power line harmonics are the result of current flowing in relatively short pulses at the positive and negative peaks of the 60 Hz cycle to charge the input filter capacitor, which is used in bo
NO! Only the "imperfections" in a transformer are inductive (and capacitive, and resistive). The relatively inductance that we see in the circuit is "leakage inductance" -- and is due to the relative
Good point of clarification here Jim! Leigh VK5KLT NO! Only the "imperfections" in a transformer are inductive (and capacitive, and resistive). The relatively inductance that we see in the circuit is
On 3/7/2013 3:07 PM, KM5VI wrote: I thought that conventional power supplies (transformer-bridge-filter) were relatively clean on reflected harmonics? Nope! Power line harmonics are the result of cu
REPLY: Jim is right. Transformers are deceptively simple as taught in first semester electronics. In fact, they are among the most complex of all basic electronic devices. Time spent hitting the tran
No, I said exactly the opposite. If it's a capacitor input filter, the current is drawn in pulses and thus has high harmonic content. A choke input filter would reduce that effect. 73, Jim K9YC _____
But yet a choke input filter will show nasty leading spikes on a scope when used in a pulsed mode such as CW and SSB. It is especially harsh with SS rectifiers and is somewhat muted with 866A/3B28's.
Until recently, past 20 or 30 years transformers have been either treated as devices in signal level circuits or in simple power circuits that did not include rectifiers. Most power electronics only
Thinking about your question and my reply, it occurred to me that you might not be aware of how Power Factor has been redefined to include both Phase Angle (the original definition) AND harmonic curr
No, the transformer is all inductive and the diodes conduct for most of the sine wave, but not all, at that transition the current changes abruptly causing distortion. (The capacitors are polar and n
Adding in the harmonics makes sense for power factor. Not in the traditional way but in the same way that Sine wave current and Cosine wave voltage produces zero Watts. Orthogonal functions, when mul
That ISO program also made companies get rid of lots of perfectly good test equipment. My shack and test benches are full of Tektronix, HP, EIP and other such gems. When I retired to Arizona, I gave
Strictly, ISO 9000 registartion means that you have the paperwork and the parts should meet the spec. Once you put self -certification to a published Harmonised Standard in the loop, it should, in th
That is an indication that the people trying for certification didn't really understand the ISO requirements. It is purely about documentation, nothing more and nothing less. I found that most compan
Strictly, ISO 9000 registartion means that you have the paperwork and the parts should meet the spec. Once you put self -certification to a published Harmonised Standard in the loop, it should, in th
REPLY: Exactly why it's a waste of time. Nobody cares about the "work process". They care about the product. A company can be in full compliance and still turn out junk. Carefully documented junk. IS
Roger, as ISO9001 goes, if you write it, you follow it! I remember going through the certification process and questioning the legitimacy of a policy that allows for non-conforming product to be ship
On 3/9/2013 8:01 PM, George wrote: Roger, as ISO9001 goes, if you write it, you follow it! I remember going through the certification process and questioning the legitimacy of a policy that allows fo