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pebe
Nobel Prize Winner
United Kingdom
1078 Posts |
 Posted - May 21 2008 : 10:59:45 AM
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The V+ is a label for a common connection. It saved having connecting lines across the drawing. Just connect all the V+ points together - not to anything else.
Yes. Connect 47R resistors if that's what the original design called for.
The rest of your points I covered in the description:
1. The period of the oscillator for 60Hz is 4.17ms. So using the formula I gave time= 0.693 x 47nF x R. So R = 4.17ms/0.693/47nF = 128K. You can use a 220K preset pot if you want.
2. All diodes are small signal diodes such as iN4148. You can use 1N4001 if you like but that's 'overkill'. |
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pebe
Nobel Prize Winner
United Kingdom
1078 Posts |
Posted - May 22 2008 : 01:25:13 AM
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| You can use any op-amp provided it has FET inputs. My favorite is a CA3140 but there are many others. |
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wasssup1990
Nobel Prize Winner
A Land Down Under
2261 Posts |
Posted - May 22 2008 : 05:04:56 AM
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Hee hee.  He even puts "Supervised by: Mr. Pebe & Mr. Audioguru". Nice one JUAN! 
What are you going to do with this schematic once it's done?
Your getting me back into the mood of building another inverter.
The last one I made was a few years ago and the Audioguru helped me out of course. |
When one person suffers from a delusion it is called insanity.
When many people suffer from a delusion it is called religion. |
Edited by - wasssup1990 on May 22 2008 05:16:41 AM |
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wasssup1990
Nobel Prize Winner
A Land Down Under
2261 Posts |
Posted - May 22 2008 : 09:54:57 AM
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Very cool. Have you thought of an inverter that, for example:
Boosts the battery voltage up to +240VDC/+120VDC & -240VDC/-120VDC and then modulates a 50/60Hz sinewave onto the PWM carrier with power being sourced from those two voltage rails? That would be very efficient wouldn't it?
Are you making this project for fun? |
When one person suffers from a delusion it is called insanity.
When many people suffer from a delusion it is called religion. |
Edited by - wasssup1990 on May 22 2008 09:56:04 AM |
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pebe
Nobel Prize Winner
United Kingdom
1078 Posts |
Posted - May 22 2008 : 10:07:49 AM
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| I'm just drawing up the low voltage cut off. It's simple! |
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pebe
Nobel Prize Winner
United Kingdom
1078 Posts |
Posted - May 22 2008 : 11:37:43 AM
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Here is the undervoltage cut-out. It uses another op-amp.
Under normal conditions, the output of the op-amp is low, so P2 and R10 form a potential divider between the 6V zener at ‘B’ and 0V. P2 slider is set to give just over 5.3V.
Modified half battery voltage comes in from P1 slider. Normally this is higher than 5.3V. The –ve input is higher than the +ve input so the op-amp’s output is low. D2 is reverse biased.
When the battery volts drop to 10V, point ‘A’ will be at 5.3V. The +ve input will then be higher than the -ve input so the op-amp output will go high. R10 now pulls up the +ve input to give positive feedback to assist the action.
D2 now conducts pulling up the reset pin of the 4017 and stops it counting. Its count is now at ‘0’ and the FETS have no drive.
C7 keeps the +ve input low at start-up and keeps the circuit off. The reset button over rides the cut-out.
Edit Note: Circuit has been edited.
Download Attachment:  Modified Sine Wave 3.GIF
4.29 KB
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Edited by - pebe on May 22 2008 12:44:05 PM |
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JUAN DELA CRUZ
Mad Scientist
Philippines
476 Posts |
Posted - May 22 2008 : 9:22:58 PM
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quote:
Originally posted by wasssup1990
Very cool. Have you thought of an inverter that, for example:
Boosts the battery voltage up to +240VDC/+120VDC & -240VDC/-120VDC and then modulates a 50/60Hz sinewave onto the PWM carrier with power being sourced from those two voltage rails? That would be very efficient wouldn't it?
Are you making this project for fun?
WASSSUP.......Johnny
The inverter that you are talking about is much "EXPENSIVE & complicated high frequency Pulse-Width-Modulation circuit to make a pure sine-wave W/ voltage feedback to regulate the level of their output voltage. I wouldn't build that kind of inverter.I would buy instead (but I don't have enough budget to buy expensive inverter, hence I build an inverter from Scratch( old components from junkshop yet it is still functioning very well)
My modified sine inverter is "CHEAPER TO BUILD" (w/ huge Xformer from microwave oven) w/ "STABLE VOLTAGE OUTPUT".
I'am just using it when their is a power cut-off.
CHEAPER BUT EFFECTIVE |
juan dela cruz
Penniless INVENTOR |
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pebe
Nobel Prize Winner
United Kingdom
1078 Posts |
Posted - May 23 2008 : 12:38:17 AM
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Hi Juan,
This circuit delays the cut-out better when the inverter is switched on.
Download Attachment: Modified Sine Wave 4.GIF
4.55 KB
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Edited by - pebe on May 23 2008 12:47:25 AM |
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pebe
Nobel Prize Winner
United Kingdom
1078 Posts |
Posted - May 24 2008 : 08:54:30 AM
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Hi Juan,
You already have a 100ohm series resistor R11 for decoupling, so you can leave out R3.
For more reliable operation, increase C4 to 1µF.
Using the revised circuit, P2 should be set to 5V, not 5.34V
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audioguru
Nobel Prize Winner
Canada
4218 Posts |
Posted - May 28 2008 : 12:02:38 AM
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Hi Juan,
Your schematic was saved as a fuzzy JPG file type which has losses. if you saved it as a GIF or PNG file type then it would be much clearer. |
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JUAN DELA CRUZ
Mad Scientist
Philippines
476 Posts |
Posted - May 28 2008 : 12:20:17 AM
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quote:
Originally posted by audioguru
Hi Juan,
Your schematic was saved as a fuzzy JPG file type which has losses. if you saved it as a GIF or PNG file type then it would be much clearer.
Hi Audioguru
I'am sorry about that fuzzy JPG File for the reason that I can't attached PNG file & GIF file has more color losses (I didn't use any special software) in making this schematic diagram just the ordinary 'Paint' in my PC.
Do you know any software that can be download from the internet for free so that I can make schematic diagram more effectively????Thanks.. |
juan dela cruz
Penniless INVENTOR |
Edited by - JUAN DELA CRUZ on May 28 2008 01:37:29 AM |
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wasssup1990
Nobel Prize Winner
A Land Down Under
2261 Posts |
Posted - May 28 2008 : 02:58:25 AM
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This one's pretty good, and it's free. I think mrgone is familure with its interface, so if you can get a hold of him he might help you.
http://www.cadsoft.de/ |
When one person suffers from a delusion it is called insanity.
When many people suffer from a delusion it is called religion. |
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pebe
Nobel Prize Winner
United Kingdom
1078 Posts |
Posted - May 28 2008 : 04:02:42 AM
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quote:
Hi Audioguru
I'am sorry about that fuzzy JPG File for the reason that I can't attached PNG file & GIF file has more color losses (I didn't use any special software) in making this schematic diagram just the ordinary 'Paint' in my PC.
Do you know any software that can be download from the internet for free so that I can make schematic diagram more effectively????Thanks..
I use the ordinary 'Paint' prog. Although when saving as a .GIF file it warns you about loss of colours, there is no loss of basic colours. I think you only lose pastel shades. |
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JUAN DELA CRUZ
Mad Scientist
Philippines
476 Posts |
Posted - May 28 2008 : 05:42:01 AM
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quote:
Originally posted by JUAN DELA CRUZ
quote:
Originally posted by wasssup1990
This one's pretty good, and it's free. I think mrgone is familure with its interface, so if you can get a hold of him he might help you.
http://www.cadsoft.de/
Thanks FOR YOUR REPLY
I'LL TRY THIS ONE http://www.cadsoft.de/
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juan dela cruz
Penniless INVENTOR |
Edited by - JUAN DELA CRUZ on May 28 2008 05:46:59 AM |
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mrgone
Nobel Prize Winner
USA
1176 Posts |
Posted - Jun 10 2008 : 09:13:21 AM
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It's pretty good! Here is a small example:
Download Attachment: Dual-SW.GIF
5.81 KB
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Edited by - mrgone on Jun 10 2008 09:18:09 AM |
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*Simple Modified-sinewave Inverter
