Range hood lights

Reply

  #1  
Old 03-01-15, 12:54 PM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
Range hood lights

I'm hoping someone here can explain what I'm doing wrong here. I've included a diagram of the circuit. I have a SPDT switch to control two lamps. "Low" should illuminate only one lamp while "High" should illuminate both lamps. A diode is in the circuit to allow power to move from left to right. The diode that was in the circuit is a 1N5404. This is a range hood that was in the house when we bought it. It has always illuminated both bulbs regardless of the switch position. I thought the diode was bad and replaced it, but, that didn't change anything. The switch position in the diagram should illuminate both bulbs. Flip the switch and only one bulb should illuminate. Name:  diode_diagram.jpg
Views: 636
Size:  12.3 KB
What am I doing wrong?
 
Sponsored Links
  #2  
Old 03-01-15, 01:22 PM
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,374
That circuit would only work as described IF you had a direct current (DC) supply.
 
  #3  
Old 03-01-15, 02:04 PM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
Thanks for your response. This is what appeared to be OEM on the range hood. Is therte a way to accomplish my objective using something other than a 1N5404 diode? What did OEM mean by this wiring (note: it didn't work)-- never mind!
 
  #4  
Old 03-01-15, 03:10 PM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
I'm a novice when it comes to this, but, when you suggest a DPDT switch, that makes sense to me. That does mean I need to try to locate switches (fan and lights) that will match up to the opening. I'm still concerned as to what OEM was doing with this circuit (Nutone NS6500). I really appreciate the input. I wish I knew more about this stuff.
 
  #5  
Old 03-01-15, 03:24 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: NJ - USA
Posts: 43,494
You don't have the diagram drawn correctly.... plus both lamps should always light..... just bright or dim. I'll be back in a few with a diagram.
 
  #6  
Old 03-01-15, 03:29 PM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
Thanks Ray! Got it! Need to get the micrometer out and take measurements. I think this switch will work. I'll make sure I let the wife knows, "Ray solved this problem." Thank you so much! You too Furd!

Mod note: My solution was wrong. See PJ's answer below.
 

Last edited by ray2047; 03-01-15 at 03:52 PM.
  #7  
Old 03-01-15, 03:31 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: NJ - USA
Posts: 43,494
This is how your lights should be wired. There is no polarity to the diode.

Name:  diode_diagram.jpg
Views: 279
Size:  16.5 KB

In high.... the 120vac is applied to both bulbs.
In low.... the diode is in series with both lamps. The diode blocks half the AC cycle and the lights are at half brightness. This circuit is used in hi/lo circuits everywhere.
 
  #8  
Old 03-01-15, 03:43 PM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
PJmax, what you diagram is probably what was there before the previous homeowner made changes. The bulbs are dimmable LED and am not seeing a difference in brightness. If I go to incandescence, I'll see a difference in brightness? I still need to think about the diode polarity you mention. Not sure what you mean.
 
  #9  
Old 03-01-15, 03:50 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 32,662
I have deleted my replies. Please follow PJ's instructions.
 
  #10  
Old 03-01-15, 04:02 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: NJ - USA
Posts: 43,494
The diode may have an effect on dimmable LED's but it will dim incandescent bulbs to half brightness.

If you try the circuit wired the way I illustrated with LED lamps.....diode polarity will affect the lamps.
 
  #11  
Old 03-01-15, 04:04 PM
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,374
Well, gee, if I had known that you were okay with both bulbs dimming I would have suggested the same as PJ.

I don't know that you will get the desired result with LED bulbs. The circuit works well with incandescents because with the diode in the circuit the bulbs get power (pulsing DC) on only one-half of the AC cycle.
 
  #12  
Old 03-01-15, 04:04 PM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
Thank you Ray, I appreciate your willingness to offer suggestions.
 
  #13  
Old 03-01-15, 04:08 PM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
I'm running out to get incandescence bulbs. I've struggled with this all weekend (and a closing Radio Shack!).
 
  #14  
Old 03-01-15, 04:29 PM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
With incandescence low has the right light brighter than the left, flip to high and the left light is brighter than the right. My wife and I think the output is the same, high or low. Matbe I should just give up! FYI, I'm still wired according to my original diagram, not what PJmax is suggesting. Too late to play with 120v. will consider following PJmax's recommendations tomorrow.
 
  #15  
Old 03-01-15, 04:51 PM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 32,662
It must be wired by PJ's diagram.
 
  #16  
Old 03-01-15, 05:02 PM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
I'll rewire tomorrow to PJmax's diagram. I really appreciate everyone's willingness to offer their knowledge.
 
  #17  
Old 03-06-15, 11:16 AM
Member
Thread Starter
Join Date: Mar 2015
Location: USA
Posts: 10
I finally found time to re-wire according to PJmax's diagram. It is now functioning correctly. Hi/Low is definitely noticeable with incandescent bulbs. I really can't see a difference with LED bulbs.
Thanks to everyone for advising me through this repair.
 
  #18  
Old 03-06-15, 11:55 AM
ray2047's Avatar
Group Moderator
Join Date: Mar 2006
Location: USA
Posts: 32,662
Thanks for letting us know the outcome.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
'