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Other Vintage Household Electrical or Electromechanical Items For discussions about other vintage (over 25 years old) electrical and electromechanical household items. See the sticky thread for details. |
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31st Dec 2019, 11:15 pm | #1 |
Hexode
Join Date: Apr 2011
Location: Stirlingshire, UK.
Posts: 407
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Using lamp current limiter
Just made up a lamp current limiter. But could not buy 100W bulbs from anywhere.
All they have are LED bulbs 8.5W 10W and current they draw is about 90mA. I plugged one of the LED bulb into the limiter, and plugged in a soldering iron of 30W. The soldering iron got hot, but less hotter than usual. And LED lamp of 8.5W never come on. Could you explain what is happening here? Thanks. Last edited by ORAWA01; 31st Dec 2019 at 11:21 pm. |
31st Dec 2019, 11:21 pm | #2 |
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Re: Using lamp current limiter
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31st Dec 2019, 11:22 pm | #3 |
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Re: Using lamp current limiter
You cannot use LED lamps in a conventional lamp limiter circuit.
The Lamp limiter relies on the fact that a cold lamp has a low resistance which increases as the lamp gets hotter. LED lamps are constant power at best. Look for Incandesent lamps or rough service lamps. Cheers Mike T
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31st Dec 2019, 11:26 pm | #4 |
Hexode
Join Date: Apr 2011
Location: Stirlingshire, UK.
Posts: 407
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Re: Using lamp current limiter
They said that they don't sell normal 100W bulbs anymore because it is not energy efficient. Max Wattage bulb they had was 40W.
I have been to 3x different local supermarkets looking for the 100W normal bulbs. I shall just have to get 40W bulbs, and change the LCL to take 2x separate bulbs of 40W each. Ahh... mail order? Maybe that's where I must look into. Thanks for the link. |
31st Dec 2019, 11:29 pm | #5 |
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Re: Using lamp current limiter
You won't get rough service lamps from a supermarket or DIY outlet.
Try an electrical wholesaler or buy online.
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Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |
31st Dec 2019, 11:33 pm | #6 |
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Re: Using lamp current limiter
It is no longer possible to legally sell 100W incandescent lamps for general use. You will need to look for professional 'rough service' lamps, or build a limiter using several lower wattage lamps in parallel. 40W 'fireglow' lamps are still available from Poundland.
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31st Dec 2019, 11:33 pm | #7 |
Rest in Peace
Join Date: Jun 2006
Location: Chard, South Somerset, UK.
Posts: 7,457
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Re: Using lamp current limiter
My local Tesco's sell 100-watt B.C. halogens.
Al. |
1st Jan 2020, 1:04 am | #8 |
Nonode
Join Date: Dec 2012
Location: Stockport, Greater Manchester, UK.
Posts: 2,102
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Re: Using lamp current limiter
If anyone wants a few 60W BC incandescents I have a crate of large globe bulbs here waiting for service as limiters.
Not sure how well they would survive in the post though
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1st Jan 2020, 2:19 am | #9 |
Dekatron
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Re: Using lamp current limiter
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Kevin |
1st Jan 2020, 10:28 am | #10 |
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Re: Using lamp current limiter
Two posts moved to this thread:-
https://www.vintage-radio.net/forum/...d.php?t=162155 I'll close this thread as there's nothing more to be said.
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Graham. Forum Moderator Reach for your meter before you reach for your soldering iron. |