Then you can rig up an experiment and prove what you said.
LPL 4500 blowing bulbs
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Those regulating electronics were expensive and I assume the standard power supply for an enlarger with halogen lamp, or any lamp deviating from the mains voltage was a plain coil transformer.
I remember that in the 80's small, plug-in transformers/rectifiers wth low output (1A) came out that were stabilized. Maybe someone with more knowledge can chime in.
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Concerning bulbs and current, I linked to graphs, even including the bulbs issue. But anyone can look for current vs. voltage graphs and see how these two behave at an resistor.
Concernung bulbs and bad connectors such will not make a incandescant lamp fail for change in current offered to it.
But there is indeed an issue. Bad connectors can lead to heating up of the socket pins of a halogen bulb and may lead to harming the pin/glass tightness. But as this pairing already is designed for gross temperature differences, substantial temperatures must be established at the pins. I wonder if this has practical effect.
Concernung bulbs and bad connectors such will not make a incandescant lamp fail for change in current offered to it.
But there is indeed an issue. Bad connectors can lead to heating up of the socket pins of a halogen bulb and may lead to harming the pin/glass tightness. But as this pairing already is designed for gross temperature differences, substantial temperatures must be established at the pins. I wonder if this has practical effect.
My experience is that no sensible conversation is possible with someone who doesn't understand something and tries to engage in a pissing contest in order to try and prove their point.
Also, as a hobby I engineer and build electronics devices including enlarger light sources and their drive and control electronics + firmware, audio devices (solid state & vacuum), which comprises the entire design chain from requirements and conceptual design through circuit design and simulation up to PCB manufacturing assembly and of course the necessary firmware development. It's a lot of fun, I'd recommend it if you're into this kind of thing. In doing so you'll also learn why the things you've said before about power, voltage and current relationships in light bulbs as well as wire gauges and cutting strands of wire are plain wrong or dangerously oversimplified.
I ran into many people in the electrical field from electrician to electrical engineer who think like ShutterFinger that if you reduce the voltage to something you increase the current. This I found came from the fact that many devices have settings for use with different voltages. If you set if for high voltage the current draw is less. If you set if for low voltage the current draw is more. But of course it's not like a light bulb. In these devices often the transformer taps are changed.
There was a story circulating of a photo of a bike 10 feet up a tree which had grown around the bike -- the story was that a young man, called away to war, chained it to the bottom of a tree and never returned.
Trees don't grow like that and when I said so, even a Botany grad argue about it with me -- she finally came around.
Trees don't grow like that and when I said so, even a Botany grad argue about it with me -- she finally came around.
https://www.allaboutcircuits.com/textbook/direct-current/chpt-2/calculating-electric-power/
the power source has to be capable of supplying the current to see the increase when lowering the voltage.
Likely an enlarger power supply does not but that doesn't change the generic formula.
Is the power on you ask. To find out take a shoe and sock off, put your foot in a bucket of water then touch the bare wire. If you light up then the power is on.
the power source has to be capable of supplying the current to see the increase when lowering the voltage.
Likely an enlarger power supply does not but that doesn't change the generic formula.
Is the power on you ask. To find out take a shoe and sock off, put your foot in a bucket of water then touch the bare wire. If you light up then the power is on.
The textbook article you link to though has it about the current increase when increasing the voltage.
Power in can exceed power draw out but if power draw out exceeds power input something in the input or output burns out oft times quickly.
And the load magically needs to drop its impedance...that's the part that keeps going over your head.
No it don't. Thanks for the bashing.
*sigh*
Whatever mate. As long as you'll never do any electrical work a where near me it's all fine.
PS: couldn't resist. Evidence of the bleeding obvious...
12V rated bulb (5W nominal) at 11.75V & 360mA = 4.23W
Same 12V rated bulb, now at 5.21V draws 250mA, so 1.3W
Oh, in case you're wondering, the power supply used is rated at 10A at 12V and 16A at 5V. Not quite sure what other kinds of smoke & mirrors you're about to diss up, but from my perspective this would be a good point for you to throw in the towel. Yes?
Oh, and this gem...
Whatever mate. As long as you'll never do any electrical work a where near me it's all fine.
PS: couldn't resist. Evidence of the bleeding obvious...
12V rated bulb (5W nominal) at 11.75V & 360mA = 4.23W
Same 12V rated bulb, now at 5.21V draws 250mA, so 1.3W
Oh, in case you're wondering, the power supply used is rated at 10A at 12V and 16A at 5V. Not quite sure what other kinds of smoke & mirrors you're about to diss up, but from my perspective this would be a good point for you to throw in the towel. Yes?
Oh, and this gem...
Please do explain how the output power of a system can exceed the input power. I'm all ears. I'm sure the people at CERN and ITER would be very interested as well. Free energy for the people!
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Bad connection won't burn out bulb except when it's bad enough to turn the light off and on quickly then it can burn out a filament just by turning on/off quickly. If a bad connection only increases resistance then the current draw will be less, the light will be dimmed, the bad connection with it higher resistance would get hot and it is the connection that eventually burned out not the light bulb.
Yes, a lamp pin can erode at a bad contact up to the point that current breaks down. The lamp thus would be still usable once new contacrt at the harmed pin is established. But as I pointed at above, leaking of the bulb due to an overheated pin is at least imaginable. And this would lead to a burn out of the filament. Such leakage at a pin is the major fault at flash bulbs. But to be fair, these are designed for different operating circumstances.
Excellent demonstration, thanks for going to the effort of setting that up to show us. Good to see Ohm's law is still working well after a couple of hundred years, well maybe not that long!
It's amazing what someone like me can learn from a poster like "shutterfinger." My electrical engineering degree and 48 years of experience, including several as an electronics bench tech, pale in comparison to the physics wisdom obtainable on the Internet. 
Now if only "shutterfinger" is willing to share its secrets enabling perpetual motion with the rest of us. Or perhaps rescue Pons and Fleishmann from ridicule by demonstrating they were right about cold fusion.
Now if only "shutterfinger" is willing to share its secrets enabling perpetual motion with the rest of us. Or perhaps rescue Pons and Fleishmann from ridicule by demonstrating they were right about cold fusion.
Actually many people who are in the electrical field made the same mistake as shutterfinger. I know the reason why also.It's amazing what someone like me can learn from a poster like "shutterfinger." My electrical engineering degree and 48 years of experience, including several as an electronics bench tech, pale in comparison to the physics wisdom obtainable on the Internet.
Now if only "shutterfinger" is willing to share its secrets enabling perpetual motion with the rest of us. Or perhaps rescue Pons and Fleishmann from ridicule by demonstrating they were right about cold fusion.
An enlarger lamphouse is a specialized lamp. I have repaired many lamps of various types, household, industrial, that frequently burned out bulbs by replacing the socket.
No special science or theory.
No special science or theory.
Ok, so effectively you did repairs, bad sockets had something to do with it but you don't exactly know why.
(My illustrative experiment of course also doesn't qualify as special science or theory; it's the kind of physics you'd typically teach 13-year olds).
(My illustrative experiment of course also doesn't qualify as special science or theory; it's the kind of physics you'd typically teach 13-year olds).
MattKing
Moderator
Folks - we have a disagreement about electricity. Let's lower the temperature a bit, to keep this thread useful.
It would be nice to know the OPs power supply type.
For the curious, the Omega D5500 power supply uses a voltage divider circuit formed by a large 2 ohm resistor and the lamp filament which goes to a true-RMS voltage sensor chip. With a poor connection at the lamp socket, the low voltage at the voltage sensor increases the triac-On time to 100% which is just like connecting the 80v lamp to the 120v mains. If, then the socket starts to conduct, the lamp blows before the PWM regulating circuit can ramp down the triac-On time. Pretty fascinating, but just for the curious.
Curative lamp socket replacement outlined here:
https://www.photrio.com/forum/threads/omega-d5500-lamp-socket-replacement.85653/
For the curious, the Omega D5500 power supply uses a voltage divider circuit formed by a large 2 ohm resistor and the lamp filament which goes to a true-RMS voltage sensor chip. With a poor connection at the lamp socket, the low voltage at the voltage sensor increases the triac-On time to 100% which is just like connecting the 80v lamp to the 120v mains. If, then the socket starts to conduct, the lamp blows before the PWM regulating circuit can ramp down the triac-On time. Pretty fascinating, but just for the curious.
Curative lamp socket replacement outlined here:
https://www.photrio.com/forum/threads/omega-d5500-lamp-socket-replacement.85653/
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