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Aaron Cake
Administrator
Canada
5722 Posts |
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tim
Mad Scientist
196 Posts |
 Posted - Feb 01 2007 : 4:47:33 PM
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| hey guys, ok i had asked if anyone had known how to locate a transistor number which was KSP44-013 well it turns out that the transistor is in fact ksp44, dont show the 013 but it must have meant something , again it turns out that there is 2 of these transistors both are 012 and 013 so the replacement is ksp 44 and ksp 45. so the differences is the voltages, 45 is lower and the 44 is higher just the opposit. and its a hi voltage npn epitaxial mosfet driver transistor. |
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Binary 1011001101
Nobel Prize Winner
United Kingdom
564 Posts |
Posted - Feb 01 2007 : 5:19:02 PM
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| Yeh thought so, the -013 wasn't part of the part number, im not sure why the -013 is there. |
Just craziness: http://munkey.hopto.org |
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cmdinh
Apprentece
9 Posts |
Posted - Feb 02 2007 : 2:08:27 PM
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after reading through 27 pages of this topic looking for a quick answer to my question... i came upon this conclusion...
if i want to step up my voltage from 12 to 120... i will need 12V transformer or also called 6-0-6 right? And depending on the power I want, i will have to select a transformer with necessary current as well.
Am i correct?? |
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CurrentOverflow
Mad Scientist
Canada
311 Posts |
Posted - Feb 02 2007 : 5:04:32 PM
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| I believe that when its a step down transformer it will turn 120Vac into 6Vac-0-6Vac, which isnt what you want. You want 12V which is a transformer that steps down to 12-0-12. Now if you consider this, putting 12V backwards onto a 12-0-12 will give you the 120VAC you want, not 6-0-6 (look at your other post :) ) |
~Mike~
Theres 10 kinds of people, those who understand binary and those who don't |
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audioguru
Nobel Prize Winner
Canada
3761 Posts |
Posted - Feb 02 2007 : 6:49:36 PM
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The transformer's center-tapped winding has the +12V battery at its center-tap, and when one end is grounded by one of the output transistors then the other end is pushed up to +24V due to transformer action.
So the 24VAC center-tapped transformer produces a 120VAC square-wave. But it needs a proper circuit to drive it with enpugh current. A 300W inverter needs to have the output transistor on each side conduct 25A.
Three paralleled 2N3055 transistors can be used on each side but their base current will be about 10A so they will need another 2N3055 transistor used as a driver. It would need to have a medium power transistor to drive it. All these old transistors can be replaced by a pair of modern Mosfets. |
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tim
Mad Scientist
196 Posts |
Posted - Feb 02 2007 : 6:58:13 PM
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| but would mosfets be good to use rather then transistors, meaning will mosfets supply enough voltage to the transformer? |
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audioguru
Nobel Prize Winner
Canada
3761 Posts |
Posted - Feb 02 2007 : 8:05:52 PM
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Choose what you want:
1) A 2N3055 transistor that has a 3V loss when it has a collector current of only 10A and is driven with a whopping 3.3A base current.
2) A modern Mosfet that has a 0.5V loss when it conducts 50A and doesn't use any gate current.
The 10A 2N3055 transistor is in a 100W inverter and its 120VAC output is actually only 90V.
The 50A Mosfet is in a 500W inverter and its 120VAC output is actually 115V.
The transistor applies only 9V to the transformer. The Mosfet applies 11.5V to the transformer. |
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essien
New Member
Nigeria
1 Posts |
Posted - Feb 03 2007 : 02:19:08 AM
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| pls i want a circuit diagram for a 2000 W inverter |
juju |
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Aaron Cake
Administrator
Canada
5722 Posts |
Posted - Feb 03 2007 : 10:28:41 AM
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quote:
Originally posted by essien
pls i want a circuit diagram for a 2000 W inverter
You didn't read this topic, did you? Inverters of that size are not practical for you to build. We've also covered this in many other topics. |
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audioguru
Nobel Prize Winner
Canada
3761 Posts |
Posted - Feb 03 2007 : 12:00:14 PM
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A 2000W inverter will draw about 200A from a 12V battery. A big car battery would explode. A bus-load of car batteries would power it for only a few hours and would take a few days to charge.
The circuit would be very expensive.
Here is a schematic of a 3000W modified sine-wave inverter. It draws 250A from a 12V (actually 13.8V) battery. It uses 16 expensive Mosfets and hundreds of other parts. Its custom-made transformer will be nearly as big and as expensive as a small car.
Download Attachment:  3000w_12.gif
54.25 KB
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cyclopsitis
Nobel Prize Winner
Canada
729 Posts |
Posted - Feb 03 2007 : 10:00:10 PM
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Where the do you get this stuff from man? haha!
Nice schematic though!
Ken |
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strike519
New Member
1 Posts |
Posted - Feb 06 2007 : 04:27:12 AM
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quote:
Originally posted by Aaron Cake
quote:
Originally posted by VOLTAGE
Are there substitutes for the HEP154 sillicon diode?
The circuit as posted on the circuits page does not work very well. But if you want to make it anyway, see the following topics regarding the diode. I just searched for "HEP154". It took less then 10 seconds to find the answer:
http://www.aaroncake.net/forum/topic.asp?TOPIC_ID=5480
http://www.aaroncake.net/forum/topic.asp?TOPIC_ID=2452
http://www.aaroncake.net/forum/topic.asp?TOPIC_ID=383
Can I use a Vrrm=600v Io=5A fast recovery diode or higher one to
raplace the HEP154 diode? because I can't find HEP154 in Taiwan.
Another question is the C1&C2. Can I use a 100uf tantalum capacitor
to replace 68uf tantalum capacitor?
Thank you for share this circuit. |
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Aaron Cake
Administrator
Canada
5722 Posts |
Posted - Feb 06 2007 : 09:37:35 AM
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quote:
Can I use a Vrrm=600v Io=5A fast recovery diode or higher one to
raplace the HEP154 diode? because I can't find HEP154 in Taiwan.
Another question is the C1&C2. Can I use a 100uf tantalum capacitor
to replace 68uf tantalum capacitor?
Sure, why not. The circuit doesn't work very well anyway. |
Edited by - Aaron Cake on Feb 08 2007 09:15:28 AM |
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cmdinh
Apprentece
9 Posts |
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Topic |
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12/120V inverter again
