ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
Potseal 11
Recent Posts
Dimmable LED 2x4 lay in fixtures
by HotLine1. 04/24/17 05:43 PM
Old decora style outlets
by Lostazhell. 04/22/17 07:59 PM
Permit Snafus...AHJs and Contractors Jump in
by gfretwell. 04/22/17 01:11 PM
How do you find a good employee?
by HotLine1. 04/22/17 10:44 AM
Electrode boilers question
by SteveFehr. 04/21/17 08:32 AM
New in the Gallery:
SE cable question
Popular Topics(Views)
234,657 Are you busy
169,363 Re: Forum
162,693 Need opinion
Who's Online Now
0 registered members (), 49 guests, and 9 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
Page 1 of 2 1 2
#67665 - 07/11/06 10:44 PM Mind bender  
Bill39  Offline
Member
Joined: Nov 2001
Posts: 75
Indianapolis, IN, USA
Here's one my son brought home from school and so far he's got me stumped:

Create a circuit in which initially, four lamps are ON while the fifth lamp is OFF. Also, you must be able to unscrew one of the four burning lamps in order to turn on the fifth lamp. You are not allowed to change any of the wiring to get this to work.

Darn College-boy!!


Work Gear for Electricians and the Trades

#67666 - 07/11/06 11:24 PM Re: Mind bender  
gfretwell  Offline


Member
Joined: Jul 2004
Posts: 9,069
Estero,Fl,usa
What kind of parts can I use?


Greg Fretwell

#67667 - 07/11/06 11:29 PM Re: Mind bender  
Bill39  Offline
Member
Joined: Nov 2001
Posts: 75
Indianapolis, IN, USA
A battery, the lamps, (& holders) & any # of wires you need.

That's it, no switches, etc. A simple circuit connected in any combination of series or parallel.


#67668 - 07/11/06 11:31 PM Re: Mind bender  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Thyristor, zenor diode and SCR to control a relay? Multiples of each could do it arranged correctly, oh a few resistors too. Also what is the voltage and current?

You posted while I was pondering...

[This message has been edited by e57 (edited 07-11-2006).]


Mark Heller
"Well - I oughta....." -Jackie Gleason

#67669 - 07/11/06 11:32 PM Re: Mind bender  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Hmmm, not legal to install? But operational?

[This message has been edited by e57 (edited 07-11-2006).]


Mark Heller
"Well - I oughta....." -Jackie Gleason

#67670 - 07/11/06 11:37 PM Re: Mind bender  
gfretwell  Offline


Member
Joined: Jul 2004
Posts: 9,069
Estero,Fl,usa
Are all of the light bulbs the same wattage?
If the 5th one was a small fraction of the others and in parallel with the one you unscrew it would work.
It sounds like one of those "all american five" radio filiment deals.


Greg Fretwell

#67671 - 07/11/06 11:39 PM Re: Mind bender  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Voltage and lamp wattage?

You guys got me again in the two minute delay of my slow typing...

[This message has been edited by e57 (edited 07-11-2006).]


Mark Heller
"Well - I oughta....." -Jackie Gleason

#67672 - 07/11/06 11:42 PM Re: Mind bender  
e57  Offline
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Thats what I was thinking too.


Mark Heller
"Well - I oughta....." -Jackie Gleason

#67673 - 07/11/06 11:46 PM Re: Mind bender  
Bill39  Offline
Member
Joined: Nov 2001
Posts: 75
Indianapolis, IN, USA
Guys,
This is a college physics lab question.
No NEC code or inspectors to worry about.

Wattage of lamps was not given. The info in my original post is all the info the prof gave them.


#67674 - 07/12/06 12:16 AM Re: Mind bender  
LarryC  Offline
Member
Joined: Jul 2004
Posts: 783
Winchester, NH, US
Hint: Brooklyn

LarryC


Page 1 of 2 1 2

Member Spotlight
sparky66wv
sparky66wv
West Virginia
Posts: 2,236
Joined: November 2000
Show All Member Profiles 
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.016s Queries: 15 (0.003s) Memory: 0.8157 MB (Peak: 0.9907 MB) Zlib enabled. Server Time: 2017-04-25 00:51:38 UTC