All About Circuits Forum  

Go Back   All About Circuits Forum > Electronics Forums > The Projects Forum

Notices

The Projects Forum Working on an electronics project and would like some suggestions, help or critiques? If you would like to comment or assist others with their projects, this is the place to do it.

Closed Thread   Post New Thread
 
Thread Tools Display Modes
  #1  
Old 10-28-2011, 08:09 PM
BrainFog BrainFog is offline
Senior Member
 
Join Date: Jan 2011
Location: England
Posts: 122
Default Optimising/Modifying Desulfator Design

Sorry about the topic being so long, I simply wish to be thorough. So many people put up topics with a lack of information making diagnosis difficult. I suspect I may not be one of them. Hopefully I haven't missed anything out.


I know a few people on here have made these and I thought this forum would benefit from a discussion about desulfators and how to modify them. This topic is also about my experiment to better understand them and how is has not turned out as expected.


It must be almost a year since I got into electronics through a project on here with the idea of making a 36v desulfator. At the time I didn't have the knowledge (in fact almost almost no electronics understanding) to build a 36v one so had to settle for making a 12v one from a thoroughly tested design which has proven to be quite effective. Recently I made another desulfator with the objective of understanding how to optimise the timing of the pulses to gain the understanding I need in order to design a 36v desulfator. Design wise it seems ok and all evidence shows it is working as it should apart from its ability to desulfate being very poor. I hope to find out where I have gone wrong and how to improve the design for my future project. I will also note that due to me using AGM's not flooded cells an equalisation charge would be damaging.


http://alton-moore.net/graphics/desulfator.pdf



It is somewhat based on the above design. I used slightly different parts but most are equivalents. The only notable differences are to L1 which I changed to self wound 70uH for experimental purposes (explained later) and used variable resistors and a 1nF capacitor to get the needed timing from the 555. The cables from the circuit to the battery are 1.5mm^2 mains cables that have been doubled up and some thin cables to a charger that are attached across C4. I have attempted to keep everything low resistance. The timing is set to 2kHz with an inductor charge time of 0.000003465 seconds, less than 1/10 of the original design, which is what I found to be the absolute maximum I could set it to without excessive heat from saturation.


Methods I used to test device (I have not yet gotten hold of an oscilloscope) are: Testing the voltage drop across a resistor in my homemade power supply in order to know exactly how much current is being consumed. This has proven to be very accurate. Using a diode and low value capacitor to test the desulfator's peak voltage output. And the old fashioned method of feeling if any of the components are hot.


The design itself seems to work, more or less. The output voltage spikes are measured at 61volts and the desulfator consumes about 55mA when the battery is fully saturated and nothing gets any more than warm. I can hear a constant hum coming from the circuit too which I know to be normal from the first one I built which works very well.


This is what the desulfator looks like. I made quite a mess of the layout in my attempt to be compact and to get short connections:



I gave my design a home wound 70uH inductor, for L1, the idea was to make it work with an inductor that will saturate after an unknown period of time. I also wanted to test if lower inductance and resistance can give more power due to more rapidly charging and discharging the inductor. I have read about the success someone had with a design that used a 22uH inductor for L1. Since I built this I have read into it some more and quite a lot of what I have read conflicts. Could anyone clear this up for me as this has most likely contributed to my desulfator being ineffective?




Even though L1 is quite small physically and in Henerys it should work more effectively than it does. I read somewhere (can't remember where now) that someone as an experiment put a capacitor across D1 to simulate high diode capacitance and found that it boosted output current but nullified the effects of the desulfator and theorised that it somehow lessened the impact of the pulse on the battery. Could the combination of diode capacitance,130pF according to the datasheet, and relatively high voltage and not massive current be my problem?


I have two main theories of what the problem may be, remember this circuit is for experimental purposes for a design that will contain unknowns. Any input and ways of improving the design will be appreciated.


A few more notes and questions:


I noticed that the mosfet heats up suddenly if I set the pulse width faster than 2 kHz, Why would this be?


How helpful are fuses in desulfators? When I first plugged it in the mosfet reached well over 100 degrees C ,to touch, within a few seconds and the fuse did not blow. I am concerned that if something goes wrong with the mosfet or timer I could end up with a house fire.


I decided to test to see if it is really worth using such thick wire with these things and the results were that if I use 1.5mm^2 wire to the battery the pulse output is 48v and with 3mm^2 it was 61v. So it does make a difference. It also explains why most commercial desulfators have such a bad reputation as they often use meters of very thin wire in which the resistance would drown out the current pulses. Although with my success I shouldn't be judging.


Thank you
  #2  
Old 10-29-2011, 12:45 AM
SgtWookie's Avatar
SgtWookie SgtWookie is offline
Expert Member
 
Join Date: Jul 2007
Location: In the vast midwest of the USA; CST
Posts: 22,032
Default

Quote:
Originally Posted by BrainFog View Post
It must be almost a year since I got into electronics through a project on here with the idea of making a 36v desulfator.
I remember that thread.

Quote:
At the time I didn't have the knowledge (in fact almost almost no electronics understanding) to build a 36v one so had to settle for making a 12v one from a thoroughly tested design which has proven to be quite effective.
Which one did you build? The original Alastair version?
You should post a schematic and parts list, or at least a link to it.

Quote:
Recently I made another desulfator with the objective of understanding how to optimise the timing of the pulses to gain the understanding I need in order to design a 36v desulfator.
Trying to go across three 12v batteries in series would be less effective than desulfating them individually. You could connect one individual desulfator across each battery.

Quote:
Design wise it seems ok
How did you come to that conclusion?

Quote:
and all evidence shows it is working as it should apart from its ability to desulfate being very poor.
That would seem to indicate that the design needs more work.

Quote:
I hope to find out where I have gone wrong and how to improve the design for my future project. I will also note that due to me using AGM's not flooded cells an equalisation charge would be damaging.
A number of AGMs can be charged at a much higher rate than standard lead-acid construction cells. You need to refer to the manufacturers' datasheet for your specific make and model, as specifications can vary even among similar product lines for a given manufacturer.

The schematic image is the original Alastair Couper design.
One caveat with Alastairs' design is that C4 is too small. If the shown timing resistor & cap are used, the small value of C4 will allow the polarity across it to reverse, which will destroy an electrolytic cap pretty rapidly. It should be at least 200uF, but larger is better. I used multiple 100uF caps rather than one large cap; this results in a much lower ESR than a single large cap.

Quote:
It is somewhat based on the above design. I used slightly different parts but most are equivalents.
One trouble with just posting the original Couper schematic is that the specifications for a number of components are rather generic; you really need to post the parts list as well.

You should also post your exact parts list.

Quote:
The only notable differences are to L1 which I changed to self wound 70uH for experimental purposes (explained later) and used variable resistors and a 1nF capacitor to get the needed timing from the 555.
How did you calculate that 70uH would substitute for 220nH, and substituting 1nF for the 22nF timing cap would compensate?

Quote:
The cables from the circuit to the battery are 1.5mm^2 mains cables that have been doubled up and some thin cables to a charger that are attached across C4. I have attempted to keep everything low resistance. The timing is set to 2kHz with an inductor charge time of 0.000003465 seconds, less than 1/10 of the original design, which is what I found to be the absolute maximum I could set it to without excessive heat from saturation.
How did you calculate this amount of ON-time, and the inductor charge time?
You're saying 3.465uS. With the standard timing resistors and your 1nF timing cap, you would get about 15.3uS ON-time.
What are you using for the values of R1 (the 470k) and R2 (the 22k) resistors?

Quote:
Methods I used to test device (I have not yet gotten hold of an oscilloscope) are: Testing the voltage drop across a resistor in my homemade power supply in order to know exactly how much current is being consumed. This has proven to be very accurate.
Just measuring across the resistor will leave something to be desired, as your meter will be getting hammered with ~60v peaks that it will have a hard time averaging.

You need to use an RC lowpass filter to remove the HV spikes.
Quote:
Using a diode and low value capacitor to test the desulfator's peak voltage output.
A 1N4148 diode works well for this. Don't forget to add the ~0.7v for the diodes' Vf to your reading.

Quote:
And the old fashioned method of feeling if any of the components are hot.
That works.

Quote:
The design itself seems to work, more or less. The output voltage spikes are measured at 61volts and the desulfator consumes about 55mA when the battery is fully saturated and nothing gets any more than warm.
55mA? Are you certain you don't mean 5.5mA? 55mA is quite high. The versions I built used around 8mA.

Quote:
I can hear a constant hum coming from the circuit too which I know to be normal from the first one I built which works very well.
It's hard to avoid the hum.


Quote:
This is what the desulfator looks like. I made quite a mess of the layout in my attempt to be compact and to get short connections:
That looks OK.
Quote:
I gave my design a home wound 70uH inductor, for L1, the idea was to make it work with an inductor that will saturate after an unknown period of time.
You want to avoid saturation, as that will quickly lead to a burned-up MOSFET. Current through an inductor increases in quite a linear fashion, until the core saturates. At that point, the winding practically becomes a straight piece of wire, and current skyrockets.

If the inductor has an air core, it won't saturate. However, you would need a LOT more wire to get the same inductance.

Core manufacturers like Micrometals have plenty of data available for you to peruse to select cores that are adequate for the task at hand.

Quote:
I also wanted to test if lower inductance and resistance can give more power due to more rapidly charging and discharging the inductor.
Well, you're kind of shooting yourself in the proverbial foot if you use small-gauge wire for winding the core.

Setting the ratio of ON to OFF time will get more critical at higher PRF's.

Quote:
I have read about the success someone had with a design that used a 22uH inductor for L1. Since I built this I have read into it some more and quite a lot of what I have read conflicts. Could anyone clear this up for me as this has most likely contributed to my desulfator being ineffective?
Small core; small gauge wire used; you are saturating the inductor.

Quote:
Even though L1 is quite small physically and in Henerys it should work more effectively than it does.
Since you don't have an O'scope, it'll be difficult to tell exactly when your inductor is entering saturation.

Quote:
I read somewhere (can't remember where now) that someone as an experiment put a capacitor across D1 to simulate high diode capacitance and found that it boosted output current but nullified the effects of the desulfator and theorised that it somehow lessened the impact of the pulse on the battery. Could the combination of diode capacitance,130pF according to the datasheet, and relatively high voltage and not massive current be my problem?
Capacitance across the diode won't help things.

But you haven't told us WHAT you're using, so it's difficult to speculate.


Quote:
I have two main theories of what the problem may be, remember this circuit is for experimental purposes for a design that will contain unknowns. Any input and ways of improving the design will be appreciated.
How about some documentation? Like, exactly what parts are you using?

Quote:
I noticed that the mosfet heats up suddenly if I set the pulse width faster than 2 kHz, Why would this be?
Pulse width is measured in time. So, 1/2kHz is 500uS, or 0.5mS. Since you have not shown us exactly how you have things wired up, all I can do is speculate that when you turn a pot to decrease the PRT, you increase the MOSFET ON-time.

Quote:
How helpful are fuses in desulfators? When I first plugged it in the mosfet reached well over 100 degrees C ,to touch, within a few seconds and the fuse did not blow. I am concerned that if something goes wrong with the mosfet or timer I could end up with a house fire.
You should use a 1A or 2A slow-blow fuse to guard against a short in the MOSFET. If you are not using a charger across C4, then you could use a somewhat smaller slow-blow fuse.

Quote:
I decided to test to see if it is really worth using such thick wire with these things and the results were that if I use 1.5mm^2 wire to the battery the pulse output is 48v and with 3mm^2 it was 61v. So it does make a difference. It also explains why most commercial desulfators have such a bad reputation as they often use meters of very thin wire in which the resistance would drown out the current pulses. Although with my success I shouldn't be judging.
The problem is the length AND diameter of the wires; even straight wires have inductance. The longer the wires, the more inductance they will have; and the parasitic inductance will decrease the effectiveness of the desulfator. If you want the best connection, use some flat, wide copper stock to connect the circuit to the battery terminals. An infinite plane has virtually no inductance; so the wider your conductors are, the less inductance they will have.
__________________
General info:
If you have a question, please start a thread/topic. I do not provide gratis assistance via PM nor E-mail, as that would violate the intent of this Board, which is sharing knowledge ... and deprives you of other knowledgeable input.
  #3  
Old 10-29-2011, 09:08 AM
BrainFog BrainFog is offline
Senior Member
 
Join Date: Jan 2011
Location: England
Posts: 122
Default

Sorry, I appear to have not given enough information after all. *tries to recover from shooting self in foot*

The parts list:
http://uk.farnell.com/multicomp/her6...00v/dp/1625098
http://uk.farnell.com/sanyo/2sj655/m...220/dp/1713433
http://uk.farnell.com/panasonic/eeef...in_merch=true&

The 555 is an NE555 if I remember correctly. Also C1 is a standard 100uF capacitor, I used a 100uF instead of a 30uF as they are easier and cheaper to obtain.
The inductors are self wound and both measured using a multimeter which measures inductance. The small one is exactly 1mH (20 turns 2500 AL) and the larger one is 70uH (about 215 AL with 18 turns).

As for the timing of the 555 I used a 555 calculator http://freespace.virgin.net/matt.wai...y/pinouts/555/
R1 is a 100k variable resistor which is now set to 5k
R2 is a 1000k variable resistor of which is set to 660k
C is 1nF for the 555
I got the resistor values by first measuring the total resistor value then measuring the resistance across the centre and unused pin to obtain the value being used by the 555.

As a power supply, I am using an L200 as a current and voltage regulator and am using a 1ohm resistor as the current sense which it uses to limit current of which all the output current passes through. I measure the voltage drop across this resistor to inform me of the output current. I assumed that the extra output capacitors on the output of the L200 would be enough to counter any fluctuations in voltage. I used 2 470uF capacitors. I remember being informed that if I place the charger across C4 it would not be subjected to the 60v current spikes. It did indeed measure 55mA not 5.5mA If this is too high the need for a filter may explain it.

I would not have called it small gauge wire. What gauge of wire would you consider appropriate? Anything thicker and physically winding it becomes very difficult. What about using parallel wires?

The goal of the 36v desulfator is to maintain already healthy batteries on a regular basis so the 36v desulfator does not need to be that effective compared to the 12v ones which I use to repair sulphated ones. Still currently this is about gaining a better understanding of them.

This is the closest I have to how a 36v desulfator might be designed (mostly states what I should try): http://home.comcast.net/%7Eddenhardt...r/highvolt.htm

Just a few concerns bout the 36v version. What would the safety risks be with a 36v desulfator? I am thinking about the high output voltage here. And what should I do to minimise risk? Also I would like to add an off switch to shut down the desulfator until I have connected everything up and am happy that I will not get shocked or create sparks. Where across the 555 would be best to add a switch in order to keep the transistor in its high resistance state without causing problems to the 555 or any other parts?

The reason I can not use an equalisation charge on AGM's is due to gaussing which is not a problem for flooded cells but with AGM batteries it would irreparably lower their total capacity. It is todo with hydrogen bubbles covering the surface of the plates lowering their usable surface area if I remember correctly.

Thank you
  #4  
Old 10-29-2011, 04:31 PM
SgtWookie's Avatar
SgtWookie SgtWookie is offline
Expert Member
 
Join Date: Jul 2007
Location: In the vast midwest of the USA; CST
Posts: 22,032
Default

Quote:
Originally Posted by BrainFog View Post
Sorry, I appear to have not given enough information after all. *tries to recover from shooting self in foot*
It happens. Particularly when one is dealing with circuits like this, that are somewhat dodgy to begin with.

The capacitor is a problem.
"AC Ripple Current: 350mA, impedance: 0.34 Ohms"
Not good. A quick simulation shows you're placing 700mA ripple current on it, and the impedance is limiting the peak current through L1.

Quote:
The 555 is an NE555 if I remember correctly. Also C1 is a standard 100uF capacitor, I used a 100uF instead of a 30uF as they are easier and cheaper to obtain.
That's fine for the 555. It should actually have another 0.1uF cap across the power/ground pins.
Quote:
The inductors are self wound and both measured using a multimeter which measures inductance. The small one is exactly 1mH (20 turns 2500 AL) and the larger one is 70uH (about 215 AL with 18 turns).
Ahh, I see. I thought the smaller toroid was your L1. I wouldn't be too surprised if L2 was starting to saturate somewhat.

Quote:
As for the timing of the 555 I used a 555 calculator http://freespace.virgin.net/matt.wai...y/pinouts/555/
R1 is a 100k variable resistor which is now set to 5k
R2 is a 1000k variable resistor of which is set to 660k
C is 1nF for the 555
I got the resistor values by first measuring the total resistor value then measuring the resistance across the centre and unused pin to obtain the value being used by the 555.
Using your values for R1 ,R2 and C1 (you have R1 & R2 reversed) in the simulation, I get exactly 2kHz for the PRF (500uS), and approximately 4uS for the pulsewidth for an 0.8% duty cycle.

Quote:
As a power supply, I am using an L200 as a current and voltage regulator and am using a 1ohm resistor as the current sense which it uses to limit current of which all the output current passes through. I measure the voltage drop across this resistor to inform me of the output current. I assumed that the extra output capacitors on the output of the L200 would be enough to counter any fluctuations in voltage. I used 2 470uF capacitors.
Again, without a complete schematic of this part of the circuit, it is difficult-to-impossible for me to tell you whether you are doing it right or not.

Quote:
I remember being informed that if I place the charger across C4 it would not be subjected to the 60v current spikes. It did indeed measure 55mA not 5.5mA If this is too high the need for a filter may explain it.
I did mention that placing a trickle charger across C4 would be OK. I also mentioned at some length about using multiple caps for C4 to lower the ESR.

Quote:
I would not have called it small gauge wire. What gauge of wire would you consider appropriate? Anything thicker and physically winding it becomes very difficult. What about using parallel wires?
As I already mentioned, you didn't state which toroid was L1, and which was L2. I'd assumed the smaller toroid was L1.

You can certainly use multiple strands of smaller gauge wire; circular mils are circular mils.

The goal of the 36v desulfator is to maintain already healthy batteries on a regular basis so the 36v desulfator does not need to be that effective compared to the 12v ones which I use to repair sulphated ones. Still currently this is about gaining a better understanding of them.

This is the closest I have to how a 36v desulfator might be designed (mostly states what I should try): http://home.comcast.net/%7Eddenhardt...r/highvolt.htm

Just a few concerns bout the 36v version. What would the safety risks be with a 36v desulfator? I am thinking about the high output voltage here. And what should I do to minimise risk? Also I would like to add an off switch to shut down the desulfator until I have connected everything up and am happy that I will not get shocked or create sparks. Where across the 555 would be best to add a switch in order to keep the transistor in its high resistance state without causing problems to the 555 or any other parts?

The reason I can not use an equalisation charge on AGM's is due to gassing which is not a problem for flooded cells but with AGM batteries it would irreparably lower their total capacity. It is todo with hydrogen bubbles covering the surface of the plates lowering their usable surface area if I remember correctly.[/QUOTE]

If you simply use three individual desulfator circuits, you avoid the overhead of having to use a regulator (the regulator draws a minimum of 5mA static current by itself) along with the regulator's power dissipation.

You also avoid the problem of having to generate a very high voltage spike, and the problems that such a high voltage spike may cause with your existing charging system and other connected circuitry.

I am not interested in designing a 36v desulfator.
__________________
General info:
If you have a question, please start a thread/topic. I do not provide gratis assistance via PM nor E-mail, as that would violate the intent of this Board, which is sharing knowledge ... and deprives you of other knowledgeable input.
  #5  
Old 10-29-2011, 06:48 PM
BrainFog BrainFog is offline
Senior Member
 
Join Date: Jan 2011
Location: England
Posts: 122
Default

Do not worry, it is me who will be designing it. This is all about improving my understanding. The purpose of the website is learning after all.

I must say I am surprised that it is the capacitor, I may never have thought of it as I chose a low ESR one. Thank you. Luckily I bought several of them and will add a couple more to lower impedance.

Just so I fully understand as I am still a bit unclear. The capacitor issue is due to the rapid discharge of the inductor at which point the circuit is completed through C4 to L1 to D1 discharging the pulse into the battery?
  #6  
Old 10-30-2011, 12:09 PM
BrainFog BrainFog is offline
Senior Member
 
Join Date: Jan 2011
Location: England
Posts: 122
Default

I have just updated my circuit by adding 2 additional 100uF low ESR capacitors in parallel with C4. Hopefully it will be enough. I also added a few aditional ceramic capacitors for the 555 and in parallel with C4.

I have also done some calculations for the RC lowpass filter. Does a resistor of 1ohm and a capacitor of 100uF sound right?

In about a week I will do a heavy drain test on my test battery to see if the desulfator is now working as it should.

Thank you for your help.
  #7  
Old 10-30-2011, 02:56 PM
SgtWookie's Avatar
SgtWookie SgtWookie is offline
Expert Member
 
Join Date: Jul 2007
Location: In the vast midwest of the USA; CST
Posts: 22,032
Default

Quote:
Originally Posted by BrainFog View Post
I have just updated my circuit by adding 2 additional 100uF low ESR capacitors in parallel with C4. Hopefully it will be enough.
There are caps available which have reasonably low ESR without paying a fortune for them. You just need to look at the specifications. For example, a Nichicon UPH1J101MRH is a 100uF 63v cap with a 0.1 Ohm ESR and an RMS current rating of 900mA. If you place three of those in parallel, you effectively wind up with 300uF, 33.3m Ohms ESR, 2.7A RMS rating; whereas before with that single 100uF cap you had more than 10x that ESR, and less than 13% the RMS current rating. See how that works?

Quote:
I also added a few aditional ceramic capacitors for the 555 and in parallel with C4.
Well, the 555 needs a 0.1uF ceramic or poly metal film AND a 1.0uF or larger alum. electrolytic nearby. You can add ceramics in parallel with C4 (etcet.) if you like, but they're probably not necessary.

Quote:
I have also done some calculations for the RC lowpass filter. Does a resistor of 1ohm and a capacitor of 100uF sound right?
It occurred to me later that you probably were not taking into account the battery charge current. So, it's likely that your 55mA current flow consisted of ~47mA charge current and ~8mA used by the desulfator circuit.

Have a look at the attached; it's basically the same circuit with just a few mods. Note R8, C8, R9; R8 provides a voltage drop for the current flow into the timer circuit, C8/R9 are the RC filter. You measure the voltage across C8 (TP2+/TP2-) to get the current flow into the timer portion of the circuit. As you can see on the plot, it's ~7.4mA after C1 charges.

Same thing with TP1+/TP1-.
If you subtract the reading across TP2 from TP1, you'll get the battery charge current. If L1 starts getting saturated, you'll see an increase across TP1+/TP1-.


Quote:
In about a week I will do a heavy drain test on my test battery to see if the desulfator is now working as it should.
You should notice the peak voltage decreasing as the sulfation gets removed.
Attached Images
File Type: png Desulfator - Brainfog's Alastair mod.png (129.3 KB, 56 views)
__________________
General info:
If you have a question, please start a thread/topic. I do not provide gratis assistance via PM nor E-mail, as that would violate the intent of this Board, which is sharing knowledge ... and deprives you of other knowledgeable input.
  #8  
Old 10-30-2011, 06:09 PM
BrainFog BrainFog is offline
Senior Member
 
Join Date: Jan 2011
Location: England
Posts: 122
Default

For some odd reason the importance of ESR during discharge did not twig until you mentioned it was most likely the capacitor. It seems to obvious now. I was only thinking about charging the inductor.

When fully saturated and only plugged into the charger the batteries only draw about 5-10ma each. It seems more likely to me that it is due to inconsistent drain as the charger is powering the desulfator. It may be a combination however, time to experiment! I will test out a few variations of RC lowpass filters and see what the results are.

I was looking for just such a schematic as that on the LTSpice yahoo group earlier today. I would really appreciate it if you could send me the .asc file or put it up on the LTSpice yahoo group.

Thanks
  #9  
Old 11-01-2011, 01:54 AM
SgtWookie's Avatar
SgtWookie SgtWookie is offline
Expert Member
 
Join Date: Jul 2007
Location: In the vast midwest of the USA; CST
Posts: 22,032
Default

Here you go.

You'll need to un-zip the zipped files and put the contents into the appropriate folders.

Make sure you rename your standard.mos to standardmos.bak before you un-zip standard.mos.zip into the cmp folder.

.asy files go in c:\Program Files\LTC\LTSpice\lib\sym\misc
.mos file goes in c:\Program Files\LTC\LTSpice\lib\cmp
.sub files goes in c:\Program Files\LTC\LTSpice\lib\sub
Attached Files
File Type: asc Desulfator - Brainfog's Alastair mod.asc (5.1 KB, 70 views)
File Type: zip LM555.zip (1.3 KB, 47 views)
File Type: zip standard.mos.zip (27.9 KB, 45 views)
File Type: zip batt_SLA.zip (3.0 KB, 41 views)
__________________
General info:
If you have a question, please start a thread/topic. I do not provide gratis assistance via PM nor E-mail, as that would violate the intent of this Board, which is sharing knowledge ... and deprives you of other knowledgeable input.
  #10  
Old 11-01-2011, 09:02 AM
BrainFog BrainFog is offline
Senior Member
 
Join Date: Jan 2011
Location: England
Posts: 122
Default

Thank you for the upload, unfortunately there appears to be a slight problem. I have double checked and all files are in the correct places. When I open up the .asc I get a popup saying "Couldn't find symbol(s): LM555dip". I have also attempted to replace the empty space on the schematic where the 555 goes with an NE555, I got the message "Singular matrix: check node m1#gate Iteration No.1"

There is an LM555 in the parts library however its pins are differently arranged.

Google did not give any usable results for the search LM555dip. What has gone wrong?
Closed Thread   Post New Thread

Tags
, ,


Related Site Pages
Section Title
Worksheet Performance-based assessments for AC circuit competencies
Worksheet Time constant circuits
Worksheet Inductors
Worksheet Capacitors
Textbook Resonance in series-parallel circuits : Resonance
Textbook CMOS 555 LONG DURATION FLYBACK LED FLASHER : 555 Timer Circuits
Textbook 555 ramp generator : Analog Integrated Circuits
Textbook Inductor transient response : Rc And L/r Time Constants
Textbook Inductors and calculus : Inductors
Textbook Magnetic fields and inductance : Inductors


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 06:31 AM.


User-posted content, unless source quoted, is licensed under a Creative Commons Public Domain License.
Powered by vBulletin
Copyright ©2000 - 2014, vBulletin Solutions, Inc.