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Hmm. That's strange.	by Longfist	2014-12-31 07:35:09
Okay, we're in CRUNCH TIME now!	by Longfist	2015-01-08 19:48:48
I just dove the web for things that do almost what	by wwill	2015-01-08 20:45:09
If it weren't for lack of a hole in the middle,	by LongFist	2015-01-09 04:59:35
2N3055s are 15A power transistors. What if we	by LongFist	2015-01-09 06:56:23
You WANT the parallel!	by ideur	2015-01-10 10:12:37
And mounted on a heat-sink! Input voltage -- 48Volt Output voltage --36Volt max current -- 22.5Amp Voltage different --> 12Volt Power "used"/dissipated in the regulator 12V x 22.5A = 270Watts!!!! --> That makes for a lot of HOT transistors. Make that 5 to 10 transistors in parallel on a HUGE heat-sink with a fan! This way the individual transistors will not get that hot and live longer. :-) You may look up the "723" voltage regulator chip. This chip has a built in over-current function (If used correctly) Have a look at "http://www.eleccircuit.com/regulator-0-30v-5a-by-ic-723-2n3055-2part/ " for a sample circuit with a 723 and some 3055's. Remember that the 723 has a maximum input voltage of about 40 volts! OR: What about a switching regulator? You still have some heat to dissipate, need to parallel a few transistors and use some HEAVY DUTY inductors ... but it might be simpler and less wasting of energy. Over-voltage protection? Have a fuse or circuit breaker and a "crowbar circuit" to short the output if you have suddenly to much voltage on the output. Feel free to ask for sample drawings or more technical info (preferable by e-mail for faster answer)
[ Reply ]
A hint:	by ideur	2015-01-11 02:49:40
Buck converter will do, switching regulator at	by wwill	2015-01-11 10:46:56
Battery overcharge isn't so much a problem.	by LongFist	2015-01-12 13:11:51
The VR chip or Zener holds the voltage and causes	by wwill	2015-01-13 09:18:11
In re the three links. Number one looks good,	by wwill	2015-01-13 09:26:51
Working on it.	by LongFist	2015-01-14 13:08:08

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