Search found 8 matches

by peterlonz
Wed Feb 17, 2010 11:17 pm
Forum: General Discussion
Topic: LED as power on indicator with AC Mains Supply
Replies: 34
Views: 5173

Re: LED as power on indicator with AC Mains Supply

Sofaspud, Thanks for your comment throughout the thread posts. Actually I never intended my comments should be interpreted to mean that I am happy to trip protection circuits about which I feel as you do. I merely said (words to the effect) that this sort of thing happens with some frequency in home...
by peterlonz
Wed Feb 17, 2010 3:08 pm
Forum: General Discussion
Topic: LED as power on indicator with AC Mains Supply
Replies: 34
Views: 5173

Re: LED as power on indicator with AC Mains Supply

OK Guys, Transformers are yesterdays solution to this specific problem. AFAIK no power strip manufacturer employs that approach. Why? Mainly cost, but also bulk, & difficulty in mounting. Am I pushing things in terms of current demand? In the judgment of a conservative technician, perhaps. In my jud...
by peterlonz
Tue Feb 16, 2010 9:59 pm
Forum: General Discussion
Topic: LED as power on indicator with AC Mains Supply
Replies: 34
Views: 5173

Re: LED as power on indicator with AC Mains Supply

The combined coincidental load on this power strip may be quite high. The rotary clothes drier would almost certainly be the biggest draw. The freezer is the smallest of the chest type. I simply have not bothered to check max demand here because: If the mains feed circuit is overloaded the main swit...
by peterlonz
Mon Feb 15, 2010 3:46 pm
Forum: General Discussion
Topic: LED as power on indicator with AC Mains Supply
Replies: 34
Views: 5173

Re: LED as power on indicator with AC Mains Supply

I don't wish to drag out indefinitely this power strip design issue but I think some points raised are worth a reply. First re safety: Most early power strip designs had no mcb, no indication & generally no switch. Later models introduced either single switches or individual socket switching & in so...
by peterlonz
Sun Feb 14, 2010 3:32 pm
Forum: General Discussion
Topic: LED as power on indicator with AC Mains Supply
Replies: 34
Views: 5173

Re: LED as power on indicator with AC Mains Supply

Jimmy, I thought along exactly the same lines. But then realised until the issue of spike management is understood there is little point in building an indicator only module. I can't see the need for providing an LED with a longer life than you'd expect from a de-rated standard 20,000 hr unit. Also ...
by peterlonz
Sat Feb 13, 2010 5:17 pm
Forum: General Discussion
Topic: LED as power on indicator with AC Mains Supply
Replies: 34
Views: 5173

Re: LED as power on indicator with AC Mains Supply

Thanks guys, I see some of the errors of assumption I made, & also how I came to calculate incorrectly the power dissipated by the 1M resistor. The author of the circuit found by Externet stated: "The resistor value was chosen to limit the worst case inrush current to about 150 mA which will drop to...
by peterlonz
Fri Feb 12, 2010 4:19 pm
Forum: General Discussion
Topic: LED as power on indicator with AC Mains Supply
Replies: 34
Views: 5173

Re: LED as power on indicator with AC Mains Supply

Thanks everyone for your suggestions. Can I make a few observations that to me are highly relevant: 1) It's no longer "usual" to use neons in this application mainly because they are not nearly bright enough & they deteriorate. 2) The link posted by Externet http://www.turbokeu.com/myprojects/acled....
by peterlonz
Thu Feb 11, 2010 11:03 pm
Forum: General Discussion
Topic: LED as power on indicator with AC Mains Supply
Replies: 34
Views: 5173

LED as power on indicator with AC Mains Supply

Hi, I'm new here & hope this question is posted in the right place. I am interested in a simple but reliable circuit that will allow an LED to indicate "power on" in a 230VAC mains circuit. I have Googled & found two circuits but neither are well explained & they differ markedly. Neither appears to ...