Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > sci.electronics.design > #518147 > unrolled thread

Abusing brick on the rope

Back to article view | Back to sci.electronics.design

Contents

  Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-02 12:55 -0700
    Re: Abusing brick on the rope tabbypurr@gmail.com - 2018-10-02 13:12 -0700
      Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-02 13:35 -0700
        Re: Abusing brick on the rope tabbypurr@gmail.com - 2018-10-02 16:13 -0700
          Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-02 17:04 -0700
            Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-02 17:19 -0700
              Re: Abusing brick on the rope tabbypurr@gmail.com - 2018-10-02 17:47 -0700
              Re: Abusing brick on the rope Lasse Langwadt Christensen <langwadt@fonz.dk> - 2018-10-02 18:16 -0700
              Re: Abusing brick on the rope Jon Elson <elson@pico-systems.com> - 2018-10-03 14:09 -0500
                Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 17:37 -0700
                Re: Abusing brick on the rope <698839253X6D445TD@nospam.org> - 2018-10-04 06:19 +0000
        Re: Abusing brick on the rope DLUNU <DecadentLinuxUserNumeroUno@DLU.org> - 2018-10-03 01:47 +0000
          Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 06:11 -0700
            Re: Abusing brick on the rope Steve Wilson <no@spam.com> - 2018-10-03 13:17 +0000
              Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 06:36 -0700
                Re: Abusing brick on the rope gnuarm.deletethisbit@gmail.com - 2018-10-03 10:02 -0700
                Re: Abusing brick on the rope krw@notreal.com - 2018-10-03 22:14 -0400
              Re: Abusing brick on the rope DLUNU <DecadentLinuxUserNumeroUno@DLU.org> - 2018-10-03 16:27 +0000
                Re: Abusing brick on the rope gnuarm.deletethisbit@gmail.com - 2018-10-03 10:04 -0700
            Re: Abusing brick on the rope DLUNU <DecadentLinuxUserNumeroUno@DLU.org> - 2018-10-03 16:25 +0000
    Re: Abusing brick on the rope piglet <erichpwagner@hotmail.com> - 2018-10-02 21:25 +0100
      Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-02 13:48 -0700
        Re: Abusing brick on the rope Jon Elson <elson@pico-systems.com> - 2018-10-03 14:15 -0500
          Re: Abusing brick on the rope Phil Allison <pallison49@gmail.com> - 2018-10-03 15:18 -0700
            Re: Abusing brick on the rope tabbypurr@gmail.com - 2018-10-03 17:26 -0700
              Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 17:52 -0700
            Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 17:45 -0700
            Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-11 12:22 -0700
    Re: Abusing brick on the rope John Robertson <spam@flippers.com> - 2018-10-02 15:32 -0700
    Re: Abusing brick on the rope Lasse Langwadt Christensen <langwadt@fonz.dk> - 2018-10-02 15:56 -0700
    Re: Abusing brick on the rope Jasen Betts <jasen@xnet.co.nz> - 2018-10-03 00:58 +0000
    Re: Abusing brick on the rope Phil Allison <pallison49@gmail.com> - 2018-10-02 23:23 -0700
      Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 06:16 -0700
    Re: Abusing brick on the rope Phil Allison <pallison49@gmail.com> - 2018-10-02 23:25 -0700
    Re: Abusing brick on the rope <698839253X6D445TD@nospam.org> - 2018-10-03 07:30 +0000
      Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 06:19 -0700
        Re: Abusing brick on the rope <698839253X6D445TD@nospam.org> - 2018-10-03 14:01 +0000
          Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 07:12 -0700
            Re: Abusing brick on the rope <698839253X6D445TD@nospam.org> - 2018-10-04 06:20 +0000
      Re: Abusing brick on the rope Jon Elson <elson@pico-systems.com> - 2018-10-03 14:20 -0500
        Re: Abusing brick on the rope Lasse Langwadt Christensen <langwadt@fonz.dk> - 2018-10-03 12:27 -0700
          Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 17:58 -0700
            Re: Abusing brick on the rope <698839253X6D445TD@nospam.org> - 2018-10-04 06:20 +0000
        Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 17:36 -0700
    Re: Abusing brick on the rope Mikko OH2HVJ <mikko.syrjalahti@nospam.fi> - 2018-10-03 12:39 +0300
      Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 06:22 -0700
    Re: Abusing brick on the rope Ingvald44 <noone@nowhere.com> - 2018-10-03 08:02 -0400
    Re: Abusing brick on the rope Jon Elson <elson@pico-systems.com> - 2018-10-03 14:07 -0500
      Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-03 17:24 -0700
        Re: Abusing brick on the rope Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-04 12:45 -0400
          Re: Abusing brick on the rope George Herold <gherold@teachspin.com> - 2018-10-04 10:01 -0700

Page 1 of 3  [1] 2 3  Next page →

#518147 — Abusing brick on the rope

Hi all, I just got done fixing a piece of apparatus that was returned to us.  The thing was trashed, (all sorts of blown components) and I've been trying to figure out what happened.  Perhaps what I found weirdest is a power monitor 
LED.  This sits across the +/-15 V rails, with a 12V zener and 5 k ohm 
resistor in series.  (the zener stops it from turning on if one of the rails 
fails.)  It just barley put out any light.... trashed.  
It can take 30 mA forward so >~150 V for too much current.  
And in reverse it doesn't break down till -80 V. 
(I just tested it... it shows a photo response too, 
but don't distract me.) 

So I was in contact with the school that was using this.. checking return 
address, and I asked if they wanted a new brick on the rope.  (Because they 
hadn't returned theirs with the unit.)  It was just then that I learned that 
the brick on the rope had failed!!  And they had purchased a new one from the 
vendor (astrodyne)  

So my current theory is that the brick on the rope failed (somehow) 
and blew 120 Vac through my circuit.. with devastating results.  
Any idea how I can test this theory.. how do I blow up a brick on a 
rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  

Thanks
George H. 
(maybe I should contact astrodyne.)       

[toc] | [next] | [standalone]

#518148

On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:
> Hi all, I just got done fixing a piece of apparatus that was returned to us.  The thing was trashed, (all sorts of blown components) and I've been trying to figure out what happened.  Perhaps what I found weirdest is a power monitor 
> LED.  This sits across the +/-15 V rails, with a 12V zener and 5 k ohm 
> resistor in series.  (the zener stops it from turning on if one of the rails 
> fails.)  It just barley put out any light.... trashed.  
> It can take 30 mA forward so >~150 V for too much current.  
> And in reverse it doesn't break down till -80 V. 
> (I just tested it... it shows a photo response too, 
> but don't distract me.) 
> 
> So I was in contact with the school that was using this.. checking return 
> address, and I asked if they wanted a new brick on the rope.  (Because they 
> hadn't returned theirs with the unit.)  It was just then that I learned that 
> the brick on the rope had failed!!  And they had purchased a new one from the 
> vendor (astrodyne)  
> 
> So my current theory is that the brick on the rope failed (somehow) 
> and blew 120 Vac through my circuit.. with devastating results.  
> Any idea how I can test this theory.. how do I blow up a brick on a 
> rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  
> 
> Thanks
> George H. 
> (maybe I should contact astrodyne.)

why would you want to blow it up when you can bypass it?


NT

[toc] | [prev] | [next] | [standalone]

#518151

On Tuesday, October 2, 2018 at 4:12:49 PM UTC-4, tabb...@gmail.com wrote:
> On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:
> > Hi all, I just got done fixing a piece of apparatus that was returned to us.  The thing was trashed, (all sorts of blown components) and I've been trying to figure out what happened.  Perhaps what I found weirdest is a power monitor 
> > LED.  This sits across the +/-15 V rails, with a 12V zener and 5 k ohm 
> > resistor in series.  (the zener stops it from turning on if one of the rails 
> > fails.)  It just barley put out any light.... trashed.  
> > It can take 30 mA forward so >~150 V for too much current.  
> > And in reverse it doesn't break down till -80 V. 
> > (I just tested it... it shows a photo response too, 
> > but don't distract me.) 
> > 
> > So I was in contact with the school that was using this.. checking return 
> > address, and I asked if they wanted a new brick on the rope.  (Because they 
> > hadn't returned theirs with the unit.)  It was just then that I learned that 
> > the brick on the rope had failed!!  And they had purchased a new one from the 
> > vendor (astrodyne)  
> > 
> > So my current theory is that the brick on the rope failed (somehow) 
> > and blew 120 Vac through my circuit.. with devastating results.  
> > Any idea how I can test this theory.. how do I blow up a brick on a 
> > rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  
> > 
> > Thanks
> > George H. 
> > (maybe I should contact astrodyne.)
> 
> why would you want to blow it up when you can bypass it?
> 
> 
> NT

Bypass how?  I've got ~100 of these out in the field (class rooms) if 
there is a way to fry the power supply that then fried the electronics 
I'd like to know.  

George H. 

[toc] | [prev] | [next] | [standalone]

#518158

On Tuesday, 2 October 2018 21:35:31 UTC+1, George Herold  wrote:
> On Tuesday, October 2, 2018 at 4:12:49 PM UTC-4, tabby wrote:
> > On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:

> > > So my current theory is that the brick on the rope failed (somehow) 
> > > and blew 120 Vac through my circuit.. with devastating results.  
> > > Any idea how I can test this theory.. how do I blow up a brick on a 
> > > rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  
> > > 
> > > Thanks
> > > George H. 
> > > (maybe I should contact astrodyne.)
> > 
> > why would you want to blow it up when you can bypass it?
> > 
> > 
> > NT
> 
> Bypass how?  I've got ~100 of these out in the field (class rooms) if 
> there is a way to fry the power supply that then fried the electronics 
> I'd like to know.  
> 
> George H.

There must be some miscommunication, as asking how to put 120v into a low voltage connector seems like a crazy question.


NT

[toc] | [prev] | [next] | [standalone]

#518162

On Tuesday, October 2, 2018 at 7:13:16 PM UTC-4, tabb...@gmail.com wrote:
> On Tuesday, 2 October 2018 21:35:31 UTC+1, George Herold  wrote:
> > On Tuesday, October 2, 2018 at 4:12:49 PM UTC-4, tabby wrote:
> > > On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:
> 
> > > > So my current theory is that the brick on the rope failed (somehow) 
> > > > and blew 120 Vac through my circuit.. with devastating results.  
> > > > Any idea how I can test this theory.. how do I blow up a brick on a 
> > > > rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  
> > > > 
> > > > Thanks
> > > > George H. 
> > > > (maybe I should contact astrodyne.)
> > > 
> > > why would you want to blow it up when you can bypass it?
> > > 
> > > 
> > > NT
> > 
> > Bypass how?  I've got ~100 of these out in the field (class rooms) if 
> > there is a way to fry the power supply that then fried the electronics 
> > I'd like to know.  
> > 
> > George H.
> 
> There must be some miscommunication, as asking how to put 120v into a low voltage connector seems like a crazy question.
> 
> 
> NT

Right sorry, I'm guessing some type of HV (>50V) out of the 
SMPS.  I'm not sure what.  So my first idea was to pound on the 
supply, somehow?  just a dead short?  There are no 'big' inductors
in this apparatus, loads are mostly resistive.  
The good news is all of the circuits had cap multipliers on the 
PS inputs, and mostly, whatever it was, just blew the unprotected 
input filter transistors.... next board spin I can add screw 
terminal blocks and call them input filter/ fuses. :^)  
to-93 pacs
2N4401/3.

The same apparatus is already using ~$2 opamps as amp/ fuses. 

George H.  

[toc] | [prev] | [next] | [standalone]

#518164

On Tuesday, October 2, 2018 at 8:04:26 PM UTC-4, George Herold wrote:
> On Tuesday, October 2, 2018 at 7:13:16 PM UTC-4, tabb...@gmail.com wrote:
> > On Tuesday, 2 October 2018 21:35:31 UTC+1, George Herold  wrote:
> > > On Tuesday, October 2, 2018 at 4:12:49 PM UTC-4, tabby wrote:
> > > > On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:
> > 
> > > > > So my current theory is that the brick on the rope failed (somehow) 
> > > > > and blew 120 Vac through my circuit.. with devastating results.  
> > > > > Any idea how I can test this theory.. how do I blow up a brick on a 
> > > > > rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  
> > > > > 
> > > > > Thanks
> > > > > George H. 
> > > > > (maybe I should contact astrodyne.)
> > > > 
> > > > why would you want to blow it up when you can bypass it?
> > > > 
> > > > 
> > > > NT
> > > 
> > > Bypass how?  I've got ~100 of these out in the field (class rooms) if 
> > > there is a way to fry the power supply that then fried the electronics 
> > > I'd like to know.  
> > > 
> > > George H.
> > 
> > There must be some miscommunication, as asking how to put 120v into a low voltage connector seems like a crazy question.
> > 
> > 
> > NT
> 
> Right sorry, I'm guessing some type of HV (>50V) out of the 
> SMPS.  I'm not sure what.  So my first idea was to pound on the 
> supply, somehow?  just a dead short?  There are no 'big' inductors
> in this apparatus, loads are mostly resistive.  
> The good news is all of the circuits had cap multipliers on the 
> PS inputs, and mostly, whatever it was, just blew the unprotected 
> input filter transistors.... next board spin I can add screw 
> terminal blocks and call them input filter/ fuses. :^)  
> to-93 pacs
> 2N4401/3.
> 
> The same apparatus is already using ~$2 opamps as amp/ fuses. 
> 
> George H.

Oh, and I need to add a bit of resistance in the power supply 
leads, where it was missing before.  
Should every low power, supply lead have 10 ohms in series? 
(low power, less than 100 mW)

George H. 

[toc] | [prev] | [next] | [standalone]

#518165

On Wednesday, 3 October 2018 01:20:00 UTC+1, George Herold  wrote:
> On Tuesday, October 2, 2018 at 8:04:26 PM UTC-4, George Herold wrote:
> > On Tuesday, October 2, 2018 at 7:13:16 PM UTC-4, tabby wrote:
> > > On Tuesday, 2 October 2018 21:35:31 UTC+1, George Herold  wrote:
> > > > On Tuesday, October 2, 2018 at 4:12:49 PM UTC-4, tabby wrote:
> > > > > On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:
> > > 
> > > > > > So my current theory is that the brick on the rope failed (somehow) 
> > > > > > and blew 120 Vac through my circuit.. with devastating results.  
> > > > > > Any idea how I can test this theory.. how do I blow up a brick on a 
> > > > > > rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  
> > > > > > 
> > > > > > Thanks
> > > > > > George H. 
> > > > > > (maybe I should contact astrodyne.)
> > > > > 
> > > > > why would you want to blow it up when you can bypass it?
> > > > > 
> > > > > 
> > > > > NT
> > > > 
> > > > Bypass how?  I've got ~100 of these out in the field (class rooms) if 
> > > > there is a way to fry the power supply that then fried the electronics 
> > > > I'd like to know.  
> > > > 
> > > > George H.
> > > 
> > > There must be some miscommunication, as asking how to put 120v into a low voltage connector seems like a crazy question.
> > > 
> > > 
> > > NT
> > 
> > Right sorry, I'm guessing some type of HV (>50V) out of the 
> > SMPS.  I'm not sure what.  So my first idea was to pound on the 
> > supply, somehow?  just a dead short?  There are no 'big' inductors
> > in this apparatus, loads are mostly resistive.  
> > The good news is all of the circuits had cap multipliers on the 
> > PS inputs, and mostly, whatever it was, just blew the unprotected 
> > input filter transistors.... next board spin I can add screw 
> > terminal blocks and call them input filter/ fuses. :^)  
> > to-93 pacs
> > 2N4401/3.
> > 
> > The same apparatus is already using ~$2 opamps as amp/ fuses. 
> > 
> > George H.
> 
> Oh, and I need to add a bit of resistance in the power supply 
> leads, where it was missing before.  
> Should every low power, supply lead have 10 ohms in series? 
> (low power, less than 100 mW)
> 
> George H.

The value that suits you depends on several things, only you can decide. How much R the thing tolerates staying within spec, how much P you want to diss, how much efficiency matters etc. A safety R can double as a fuse.


NT

[toc] | [prev] | [next] | [standalone]

#518169

onsdag den 3. oktober 2018 kl. 02.20.00 UTC+2 skrev George Herold:
> On Tuesday, October 2, 2018 at 8:04:26 PM UTC-4, George Herold wrote:
> > On Tuesday, October 2, 2018 at 7:13:16 PM UTC-4, tabb...@gmail.com wrote:
> > > On Tuesday, 2 October 2018 21:35:31 UTC+1, George Herold  wrote:
> > > > On Tuesday, October 2, 2018 at 4:12:49 PM UTC-4, tabby wrote:
> > > > > On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:
> > > 
> > > > > > So my current theory is that the brick on the rope failed (somehow) 
> > > > > > and blew 120 Vac through my circuit.. with devastating results.  
> > > > > > Any idea how I can test this theory.. how do I blow up a brick on a 
> > > > > > rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  
> > > > > > 
> > > > > > Thanks
> > > > > > George H. 
> > > > > > (maybe I should contact astrodyne.)
> > > > > 
> > > > > why would you want to blow it up when you can bypass it?
> > > > > 
> > > > > 
> > > > > NT
> > > > 
> > > > Bypass how?  I've got ~100 of these out in the field (class rooms) if 
> > > > there is a way to fry the power supply that then fried the electronics 
> > > > I'd like to know.  
> > > > 
> > > > George H.
> > > 
> > > There must be some miscommunication, as asking how to put 120v into a low voltage connector seems like a crazy question.
> > > 
> > > 
> > > NT
> > 
> > Right sorry, I'm guessing some type of HV (>50V) out of the 
> > SMPS.  I'm not sure what.  So my first idea was to pound on the 
> > supply, somehow?  just a dead short?  There are no 'big' inductors
> > in this apparatus, loads are mostly resistive.  
> > The good news is all of the circuits had cap multipliers on the 
> > PS inputs, and mostly, whatever it was, just blew the unprotected 
> > input filter transistors.... next board spin I can add screw 
> > terminal blocks and call them input filter/ fuses. :^)  
> > to-93 pacs
> > 2N4401/3.
> > 
> > The same apparatus is already using ~$2 opamps as amp/ fuses. 
> > 
> > George H.
> 
> Oh, and I need to add a bit of resistance in the power supply 
> leads, where it was missing before.  
> Should every low power, supply lead have 10 ohms in series? 
> (low power, less than 100 mW)
> 

transorb and polyfuse? over voltage disconnect with some high voltage transistors?

[toc] | [prev] | [next] | [standalone]

#518231

On Tue, 02 Oct 2018 17:19:54 -0700, George Herold wrote:


> Oh, and I need to add a bit of resistance in the power supply leads,
> where it was missing before.
> Should every low power, supply lead have 10 ohms in series?
> (low power, less than 100 mW)

Use a big resistor, they are less likely to flash over in a crazy event.

Jon

[toc] | [prev] | [next] | [standalone]

#518280

On Wednesday, October 3, 2018 at 3:09:28 PM UTC-4, Jon Elson wrote:
> On Tue, 02 Oct 2018 17:19:54 -0700, George Herold wrote:
> 
> 
> > Oh, and I need to add a bit of resistance in the power supply leads,
> > where it was missing before.
> > Should every low power, supply lead have 10 ohms in series?
> > (low power, less than 100 mW)
> 
> Use a big resistor, they are less likely to flash over in a crazy event.
> 
> Jon

Hmm maybe a smaller resistor turns into a fuse?
GH

[toc] | [prev] | [next] | [standalone]

#518302

Jon Elson wrote

>On Tue, 02 Oct 2018 17:19:54 -0700, George Herold wrote:
>
>
>> Oh, and I need to add a bit of resistance in the power supply leads,
>> where it was missing before.
>> Should every low power, supply lead have 10 ohms in series?
>> (low power, less than 100 mW)
>
>Use a big resistor, they are less likely to flash over in a crazy event.
>
>Jon

Hey! incandescent  low voltage light bulbs, car rear lights?
Those have a cold resistance of 1/10 of normal,
sort of PTC protection..
And visual indication things are wrong.
;-)

[toc] | [prev] | [next] | [standalone]

#518170

George Herold <gherold@teachspin.com> wrote in
news:69b19472-7334-4d87-9eb7-598e206a9036@googlegroups.com: 

> On Tuesday, October 2, 2018 at 4:12:49 PM UTC-4, tabb...@gmail.com
> wrote: 
>> On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:
>> > Hi all, I just got done fixing a piece of apparatus that was
>> > returned to us.  The thing was trashed, (all sorts of blown
>> > components) and I've been trying to figure out what happened. 
>> > Perhaps what I found weirdest is a power monitor LED.  This sits
>> > across the +/-15 V rails, with a 12V zener and 5 k ohm resistor in
>> > series.  (the zener stops it from turning on if one of the rails 
>> > fails.)  It just barley put out any light.... trashed.  
>> > It can take 30 mA forward so >~150 V for too much current.  
>> > And in reverse it doesn't break down till -80 V. 
>> > (I just tested it... it shows a photo response too, 
>> > but don't distract me.) 
>> > 
>> > So I was in contact with the school that was using this.. checking
>> > return address, and I asked if they wanted a new brick on the rope.
>> >  (Because they hadn't returned theirs with the unit.)  It was just
>> > then that I learned that the brick on the rope had failed!!  And
>> > they had purchased a new one from the vendor (astrodyne)  
>> > 
>> > So my current theory is that the brick on the rope failed (somehow)
>> > and blew 120 Vac through my circuit.. with devastating results.  
>> > Any idea how I can test this theory.. how do I blow up a brick on a
>> > rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  
>> > 
>> > Thanks
>> > George H. 
>> > (maybe I should contact astrodyne.)
>> 
>> why would you want to blow it up when you can bypass it?
>> 
>> 
>> NT
> 
> Bypass how?  I've got ~100 of these out in the field (class rooms) if 
> there is a way to fry the power supply that then fried the electronics
> I'd like to know.  
> 
> George H. 

  It sounds like the result of a severe transient (lightning strike) on 
the input line to the brick which then passed it through in a rare 
failure mode.

  Instead of trying to recreate the failure, diagnose the failed unit 
you already have and see if the isolated AC input side found a path 
through the PS to the output side.

  What device are you running that requires a dual output supply? That 
itself is an odd instance.

[toc] | [prev] | [next] | [standalone]

#518193

On Tuesday, October 2, 2018 at 9:47:28 PM UTC-4, DLUNU wrote:
> George Herold <gherold@teachspin.com> wrote in
> news:69b19472-7334-4d87-9eb7-598e206a9036@googlegroups.com: 
> 
> > On Tuesday, October 2, 2018 at 4:12:49 PM UTC-4, tabb...@gmail.com
> > wrote: 
> >> On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:
> >> > Hi all, I just got done fixing a piece of apparatus that was
> >> > returned to us.  The thing was trashed, (all sorts of blown
> >> > components) and I've been trying to figure out what happened. 
> >> > Perhaps what I found weirdest is a power monitor LED.  This sits
> >> > across the +/-15 V rails, with a 12V zener and 5 k ohm resistor in
> >> > series.  (the zener stops it from turning on if one of the rails 
> >> > fails.)  It just barley put out any light.... trashed.  
> >> > It can take 30 mA forward so >~150 V for too much current.  
> >> > And in reverse it doesn't break down till -80 V. 
> >> > (I just tested it... it shows a photo response too, 
> >> > but don't distract me.) 
> >> > 
> >> > So I was in contact with the school that was using this.. checking
> >> > return address, and I asked if they wanted a new brick on the rope.
> >> >  (Because they hadn't returned theirs with the unit.)  It was just
> >> > then that I learned that the brick on the rope had failed!!  And
> >> > they had purchased a new one from the vendor (astrodyne)  
> >> > 
> >> > So my current theory is that the brick on the rope failed (somehow)
> >> > and blew 120 Vac through my circuit.. with devastating results.  
> >> > Any idea how I can test this theory.. how do I blow up a brick on a
> >> > rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A / -15V @ -1A.  
> >> > 
> >> > Thanks
> >> > George H. 
> >> > (maybe I should contact astrodyne.)
> >> 
> >> why would you want to blow it up when you can bypass it?
> >> 
> >> 
> >> NT
> > 
> > Bypass how?  I've got ~100 of these out in the field (class rooms) if 
> > there is a way to fry the power supply that then fried the electronics
> > I'd like to know.  
> > 
> > George H. 
> 
>   It sounds like the result of a severe transient (lightning strike) on 
> the input line to the brick which then passed it through in a rare 
> failure mode.
> 
>   Instead of trying to recreate the failure, diagnose the failed unit 
> you already have and see if the isolated AC input side found a path 
> through the PS to the output side.
> 
>   What device are you running that requires a dual output supply? That 
> itself is an odd instance.

Right, I just don't know.  The professor seems adamant that the students did something wrong.  
I can't diagnose the failed supply, 'cause I ain't got it.  

Dual supply +/-15V is for opamps.  I know they are rare these days (split supplies), but at the time it was easier than splitting some single supply.

George H. 

[toc] | [prev] | [next] | [standalone]

#518195

George Herold <gherold@teachspin.com> wrote:

> Dual supply +/-15V is for opamps.  I know they are rare these days
> (split supplies), but at the time it was easier than splitting some
> single supply. 
 
> George H. 


What is brick on a rope? Where does the rope come from?

[toc] | [prev] | [next] | [standalone]

#518199

On Wednesday, October 3, 2018 at 9:17:25 AM UTC-4, Steve Wilson wrote:
> George Herold <gherold@teachspin.com> wrote:
> 
> > Dual supply +/-15V is for opamps.  I know they are rare these days
> > (split supplies), but at the time it was easier than splitting some
> > single supply. 
>  
> > George H. 
> 
> 
> What is brick on a rope? Where does the rope come from?

A brick on a rope is a desk top power supply, as opposed to a 
wall wart, which plugs right into the wall with no intermediate 
AC power line.  
Typically they have more power.  

George H. 

[toc] | [prev] | [next] | [standalone]

#518217

On Wednesday, October 3, 2018 at 9:36:33 AM UTC-4, George Herold wrote:
> On Wednesday, October 3, 2018 at 9:17:25 AM UTC-4, Steve Wilson wrote:
> > George Herold <gherold@teachspin.com> wrote:
> > 
> > > Dual supply +/-15V is for opamps.  I know they are rare these days
> > > (split supplies), but at the time it was easier than splitting some
> > > single supply. 
> >  
> > > George H. 
> > 
> > 
> > What is brick on a rope? Where does the rope come from?
> 
> A brick on a rope is a desk top power supply, as opposed to a 
> wall wart, which plugs right into the wall with no intermediate 
> AC power line.  
> Typically they have more power.  

Lol!  Have you done an internet search on "brick on a rope"? 

Rick C. 

[toc] | [prev] | [next] | [standalone]

#518290

On Wed, 3 Oct 2018 06:36:29 -0700 (PDT), George Herold
<gherold@teachspin.com> wrote:

>On Wednesday, October 3, 2018 at 9:17:25 AM UTC-4, Steve Wilson wrote:
>> George Herold <gherold@teachspin.com> wrote:
>> 
>> > Dual supply +/-15V is for opamps.  I know they are rare these days
>> > (split supplies), but at the time it was easier than splitting some
>> > single supply. 
>>  
>> > George H. 
>> 
>> 
>> What is brick on a rope? Where does the rope come from?
>
>A brick on a rope is a desk top power supply, as opposed to a 
>wall wart, which plugs right into the wall with no intermediate 
>AC power line.  
>Typically they have more power.  

We've always called that "lump in line".

[toc] | [prev] | [next] | [standalone]

#518214

Steve Wilson <no@spam.com> wrote in news:XnsA9705E7E0A0A7idtokenpost@
69.16.179.23:

> 
> What is brick on a rope? Where does the rope come from?
> 

You have never heard the term "wall wart"?  This is like that.

  A small "brick" type power supply (usually in a plastic case)
in an inline configuration. ergo:  "a brick on a rope".

[toc] | [prev] | [next] | [standalone]

#518218

On Wednesday, October 3, 2018 at 12:27:26 PM UTC-4, DLUNU wrote:
> Steve Wilson <no@spam.com> wrote in news:XnsA9705E7E0A0A7idtokenpost@
> 69.16.179.23:
> 
> > 
> > What is brick on a rope? Where does the rope come from?
> > 
> 
> You have never heard the term "wall wart"?  This is like that.
> 
>   A small "brick" type power supply (usually in a plastic case)
> in an inline configuration. ergo:  "a brick on a rope".

Usually simply called a power supply brick.  Lots of things come in brick form. 

Rick C. 

[toc] | [prev] | [next] | [standalone]

#518213

George Herold <gherold@teachspin.com> wrote in
news:855d16d5-db6d-4d97-ad6f-63761c955eea@googlegroups.com: 

> On Tuesday, October 2, 2018 at 9:47:28 PM UTC-4, DLUNU wrote:
>> George Herold <gherold@teachspin.com> wrote in
>> news:69b19472-7334-4d87-9eb7-598e206a9036@googlegroups.com: 
>> 
>> > On Tuesday, October 2, 2018 at 4:12:49 PM UTC-4, tabb...@gmail.com
>> > wrote: 
>> >> On Tuesday, 2 October 2018 20:56:03 UTC+1, George Herold  wrote:
>> >> > Hi all, I just got done fixing a piece of apparatus that was
>> >> > returned to us.  The thing was trashed, (all sorts of blown
>> >> > components) and I've been trying to figure out what happened. 
>> >> > Perhaps what I found weirdest is a power monitor LED.  This sits
>> >> > across the +/-15 V rails, with a 12V zener and 5 k ohm resistor
>> >> > in series.  (the zener stops it from turning on if one of the
>> >> > rails fails.)  It just barley put out any light.... trashed.  
>> >> > It can take 30 mA forward so >~150 V for too much current.  
>> >> > And in reverse it doesn't break down till -80 V. 
>> >> > (I just tested it... it shows a photo response too, 
>> >> > but don't distract me.) 
>> >> > 
>> >> > So I was in contact with the school that was using this..
>> >> > checking return address, and I asked if they wanted a new brick
>> >> > on the rope. 
>> >> >  (Because they hadn't returned theirs with the unit.)  It was
>> >> >  just 
>> >> > then that I learned that the brick on the rope had failed!!  And
>> >> > they had purchased a new one from the vendor (astrodyne)  
>> >> > 
>> >> > So my current theory is that the brick on the rope failed
>> >> > (somehow) and blew 120 Vac through my circuit.. with devastating
>> >> > results.  Any idea how I can test this theory.. how do I blow up
>> >> > a brick on a rope?  (Astrodyne Mod num. SPU45-210) +15 V @ +2A /
>> >> > -15V @ -1A.  
>> >> > 
>> >> > Thanks
>> >> > George H. 
>> >> > (maybe I should contact astrodyne.)
>> >> 
>> >> why would you want to blow it up when you can bypass it?
>> >> 
>> >> 
>> >> NT
>> > 
>> > Bypass how?  I've got ~100 of these out in the field (class rooms)
>> > if there is a way to fry the power supply that then fried the
>> > electronics I'd like to know.  
>> > 
>> > George H. 
>> 
>>   It sounds like the result of a severe transient (lightning strike)
>>   on 
>> the input line to the brick which then passed it through in a rare 
>> failure mode.
>> 
>>   Instead of trying to recreate the failure, diagnose the failed unit
>> you already have and see if the isolated AC input side found a path 
>> through the PS to the output side.
>> 
>>   What device are you running that requires a dual output supply?
>>   That 
>> itself is an odd instance.
> 
> Right, I just don't know.  The professor seems adamant that the
> students did something wrong.  I can't diagnose the failed supply,
> 'cause I ain't got it.  
> 
> Dual supply +/-15V is for opamps.  I know they are rare these days
> (split supplies), but at the time it was easier than splitting some
> single supply. 
> 
> George H. 
> 

You could build an inline "minibrick" -15V supply to hang on the end of 
a standard well made supply, and have a pass thru output cable pair that 
gives you both.  I know that sounds odd, but I would put more faith into 
a more common off the shelf robust single output supply and your in-
house made add on than apparently what you chose.  They sound like they 
may be the problem.

[toc] | [prev] | [next] | [standalone]

Page 1 of 3  [1] 2 3  Next page →

Back to top | Article view | sci.electronics.design

csiph-web