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    protecting 24vac motor controller - zener, MOV or both?

    Thanks for the info.  I've been searching for a 33v mov, but there doesn't seem to be any.  Here's one that is close, a 30vac mov.  Open circuit voltage on the transformer is 26 vac. V47ZA3 Max applied voltage:    30 V Acrms,  38 V DC Max energy, 2ms:        4.5 J Clamping voltage:      93 V...
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    protecting 24vac motor controller - zener, MOV or both?

    I can't put it on the AC side of the transformer, because it is in the attic somewhere.  Exactly where, I'm not sure.  Anyway, I read somewhere that protection components are best placed on the board, right where the power enters.  The idea is that inductive surges from lightning, etc. are also...
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    protecting 24vac motor controller - zener, MOV or both?

    I had a recent power failure that blew out routers, hard wired smoke detectors, etc.  The most painful was a pic-based motor controller that runs off of 24vac. Now that I've replaced everything, I would like to protect the motor controller.  From what I've read, I could use opposing Zeners on...
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    Need help saturating a transistor for 2 amps

    By the way, most people seem to refer to a transistor in switching mode as "saturated", is there a more correct term for that?
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    Need help saturating a transistor for 2 amps

    You're right, the datasheets for NTE semiconductors aren't like others I've seen.  Anyway, I found out that NTE2343 cross references to TIP102.  Luckily, fairchild has plots for the tip102.  I hope that has the necessary info  ;D   http://www.fairchildsemi.com/ds/TI/TIP102.pdf
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    Need help saturating a transistor for 2 amps

    indulis:  I'm a newbie.  Newbie + static sensitive parts = poof ;) audioguru:  I could not get a tip120, I ended up with an NTE2343. Also a darlington npn, supposed to similar and handles more power.   http://www.nteinc.com/specs/2300to2399/NTE2343.html Any difference in the calcs?  Is there...
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    Need help saturating a transistor for 2 amps

    Thanks the info, audioguru. I plan on using a readily available led, which means Radio Shack  :o   http://www.radioshack.com/product/index.jsp?productId=2062553 This led does need a current limiting resistor.  It is Vf 2.25, 90mA.  If the darlington turns on at 1mA, will 50mA thru the base...
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    Need help saturating a transistor for 2 amps

    Hi, I need to blink an array of 78 white leds.  I figure that I need to switch about 4.0 volts at 1.6 amps. I want to take a $1.00 blinky led as a signal source and drive a TIP120 with it.  When using a TIP120 as a switch, can I just wire it in series with the LED array ground connection? ...
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