1N540X series are *not* stud diodes. No metal can. No screw thread. In fact I'd have positively recommended them.
Mouser is clearly berserk.
See....
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Graham
A Bridge Replacement A Good Idea?
Sep 17, 2005
55 Replies
culpa.
beefier part if
burning.
No, you're right. I haven't had to deal with that kind of gear. Just look on in awe! Everything to date I've designed will run off a wall socket although it may be pushing it with a standard 20A US Edison outlet.
Your point understood. Not relevant to lighter duty stuff IMHO though. I don't think I've ever met an FF fuse IRL.
Graham
Maybe Ron doesn't understand what a real stud diode is ? Been a long long time since I last saw one.
Graham
How do you do a parametric search at Mouser?
Best regards, Spehro Pefhany
"it\'s the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
back I had a small
metal film R as combined R
sub-contractor couldn't find
'blowing', so it's back to a
Why didn't you spec a fusible cement-type WW?
Best regards, Spehro Pefhany
"it\'s the network..." "The Journey is the reward"
speff@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com
I have a Jewish friend who owns a cheese store named "Cheeses of
Nazareth."
"Ron Hubbard"
** What the heck makes you think that a 2.5 amp diode is a "stud" type ??Go check the 1N5408 out.
........... Phil
** Correct - the fuse ( assumed to be slo-blo) will open at a current a little over 1 amp rms.
The diodes heat according to the average rectified current value (a significantly smaller number than the rms one) and each diode only sees half the current pulses that the fuse does.
Long as the fuse is a genuine 1 amp - it will pop first.
.......... Phil
"Pooh Bear"
** A max 34 amp surge into say, a 100uF electro, will only happen by sheer chance at a switch on. So the worst case, initial rate of rise of voltage is I / C = 340,000 volts per second or 340 volts per mS. The surge event is very brief, 3.R.C at most - so all over in 2 or 3 mS.The electro will not be fully discharged by the zenon lamp flash but drop to about 40% of the initial voltage - further lessoning surges.
A slo-blo fuse rated at 1 amp will survive 10 amps for half cycles, non repetitive, but open if the current pulse goes much above that.
.......... Phil
while back I had a small
metal film R as combined R
sub-contractor couldn't find
'blowing', so it's back to a
Actually I haven't seen such a part before.
Do you have a link ?
Graham
time
If I try " 3A 1000V diode " I get the 1N5408 as first hit but it doesn't say stud diode at all. Rather....
Diodes Inc. Rectifier - Standard DO-201AD Vr/1000V
Graham
Why worry about big diodes. I would worry about blowing the MOC3020 or trying to turn the darn thing off. Looks like a lot of smoke to me. Hey poo, electronics 101 would of caught that! Harry
I read in sci.electronics.design that Pooh Bear wrote (in ) about 'A Bridge Replacement A Good Idea?', on Sun, 18 Sep 2005:
Maybe some catalogue, somewhere, says 'Std DO-201AD'.
Regards, John Woodgate, OOO - Own Opinions Only.
If everything has been designed, a god designed evolution by natural selection.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk
"John Popelish"
** Change your supplier.Mine are all 100 milliohms, tops.
........... Phil
** I am not - real all the points before sticking foot in mouth. ** That is on the BASIC schematic only - the text discusses using capacitances of over 100uF. ** Insanity - ordinary fuses do exactly that, day in day out, in millions of pieces of gear.
.......... Phil
** Try learning to read with context - Pooh.
............ Phil
Isn't there a 'holding value' of If for SCRs ? Been ages since I looked at one. Can't see much smoke happening with that 100k R4 in the way though.
Graham
"John Popelish"
** See:
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The voltage drop at 1 amp (for a 1 amp rated fuse) is 150 mV max ( so 150 milliohms hot) - this appears to be the IEC 127 standard.
and:
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A 1 amp sample is speced at 55 milliohms when cold !!!!
It just depends exactly what metal the fuse wire is made from.
If tinned copper, the melting temp is high - so the resistance needs to be higher to supply the needed heat energy.
If pure tin, the melting temp is way lower - so the resistance can be too.
Simple.
............ Phil
** No - he was alluding to his own earlier post and NOT my words -
ie " ... those stud diodes I previously mentioned ... "
** A "stud" refers to a " mounting stud " or short thread - AFAIK.Then there are the "press fit " types that go inside automotive alternators.
Mostly, I see chunky bridge rectifiers rated at 40 or 50 amps in large amplifiers - sometimes two of 'em. .
......... Phil
"Spehro Pefhany"
** Errr - enter the names of all your favourite cheeses ???....... Phil
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