I studied the schematic diagrams of some SMPS designs.
There I found circuits called 'Dynamic load'.
What does it mean by that??
Regards
Abut 35 years ago I was a very junior tech wire wrapping "logic boards" for
a hug security console that contained a drum printer, clock and annauciator
panel consisting of hundreds of lights denouncing what the various portals in
plant were open or closed. There was more to it but I don' remember. The
project went smoothly and was delivered on time and within the budget. We
invited the chief of security to the command post and briefed him on various
operations. In the midst of getting familiar with various functions he asked
"And what is this button marked LT do?" "Oh that is the Lamp Test button. It
turns on all of the annauciator lamps on at once so that you can easily spot
if any are burned out. Go ahead, try it I urged him wit confidence." So he
pushes the button and there is a groan from underneath the console as the SCR
regulated power supply struggles to keep up with the load. Every light (
there were hundreds of them) light up and he satisfyingly lets go of the
button. There was tick sound followed by snap crackle and pop as every
circuit board self destructed. Lots of smoke too. Although we tested the
lamp test function we did not test it under the full load. Back in the lab
we discovered that when the full load of 20 or so amps was suddenly reduced
to 1Amp, the 5 volt "regulated" output shot up to 20 volts. That is when I
learned the importance of verifying the dynamic load.
Regards,
Boris Mohar
Got Knock? - see:
Viatrack Printed Circuit Designs (among other things)
http://www.viatrack.ca
void _-void-_ in the obvious place
