DC input jack has 3 terminals ?

johnviera · 18th August 2011, 01:49 AM

Why do DC input jacks have 3 terminals? Positive (+) Negative (-) and (?)?

Ground ??? Isn't Ground the same as negative ?

Like these: http://img.alibaba.com/wsphoto/v0/48...pg_200x200.jpg

JV

Jim McPherson · 18th August 2011, 02:35 AM

Ground != negative on many amplifiers. For instance: Many Tripath amps require -45v, +45v and "ground".

-Jim

theAnonymous1 · 18th August 2011, 02:44 AM

Two of the terminals are touching when there isn't a plug inserted. When you insert a plug they disconnect, leaving only one in contact with the plug.

You could use this to charge a battery powered device. Inserting a plug would disconnect the load from the battery so only the battery is connnected to the charger.

I'm sure there are other uses as well.

CONN 2.1MM JACK W/HARD PNL MNT - PJ-005A

johnviera · 18th August 2011, 03:35 AM

Thanks. I see the short when disconnected and no short when plug is inserted. Thanks.

zerokelvin99 · 18th August 2011, 10:24 PM

little voltage, big voltage and HUGEEEE VOLTAGE

..

sorry

18th August 2011, 01:49 AM	#1
johnviera diyAudio Member Join Date: Aug 2011	DC input jack has 3 terminals ? Why do DC input jacks have 3 terminals? Positive (+) Negative (-) and (?)? Ground ??? Isn't Ground the same as negative ? Like these: http://img.alibaba.com/wsphoto/v0/48...pg_200x200.jpg JV

18th August 2011, 02:44 AM	#3
theAnonymous1 diyAudio Member Join Date: Feb 2004 Location: Anonymityville	Two of the terminals are touching when there isn't a plug inserted. When you insert a plug they disconnect, leaving only one in contact with the plug. You could use this to charge a battery powered device. Inserting a plug would disconnect the load from the battery so only the battery is connnected to the charger. I'm sure there are other uses as well. CONN 2.1MM JACK W/HARD PNL MNT - PJ-005A __________________ "If you don't like funerals don't kick sand in Ninja's face." - Ninja

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Isolating RCA input/terminals from enclosure	bobsagat666	Chip Amps	5	12th July 2011 07:06 PM
DC panel mount jack orientation	gychang	Construction Tips	0	20th May 2011 01:21 AM
What is acceptable DC offset on speaker terminals?	valterdaw	Car Audio	3	3rd December 2007 09:01 PM
Terminals for 12V DC/DC input	Pierre	Power Supplies	4	8th May 2007 07:11 AM
Problem with high DC on speaker terminals	Phear	Chip Amps	5	13th February 2004 02:18 PM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read


	Please consider donating to help us continue to serve you. Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving

18th August 2011, 02:35 AM	#2
Jim McPherson diyAudio Member Join Date: Jun 2004 Location: Maryland, USA	Ground != negative on many amplifiers. For instance: Many Tripath amps require -45v, +45v and "ground". -Jim

18th August 2011, 03:35 AM	#4
johnviera diyAudio Member Join Date: Aug 2011	Thanks. I see the short when disconnected and no short when plug is inserted. Thanks.

18th August 2011, 10:24 PM	#5
zerokelvin99 diyAudio Member Join Date: Apr 2010 Location: uk	little voltage, big voltage and HUGEEEE VOLTAGE .. sorry

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)