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| why is the US not Metric |
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| Rerouter:
More marketing departments seem terrified of decimal points, leading to them using what ever unit gets there point across, e.g. if they want it to sound really big, or really small, either way you end up needing roughly 3 significant digits to actually know what to expect. That and really stupid research that shows certain regions are biased towards lower economy numbers "Because that means less fuel is used" until they spend a few seconds actively thinking about it Personally prefer L/100km for the work I do, because I have seen the above effect first hand far too many times, They want there trucks to burn less fuel, not travel further, Yes I know what I said, and I have given up hope of winning that argument. |
| vad:
--- Quote from: james_s on October 26, 2019, 04:56:16 pm ---Have you looked into the cost of 10AWG wire or calculated the losses you'd end up with? --- End quote --- Yes, I did few messages above. I’ll spare you from searching. 1.5V voltage drop (11% power loss at 12V at receptacle, 6% power loss with 24V at receptacle). And that’s at maximum load at furthest distance. I doubt AC-DC converter in a typical A19 LED bulb has near that efficiency. 250ft roll of 10/2 Romex is $130 at the nearest Home Depot. 12/2 is $60, 14/2 is $40. You need 3 rolls to wire 10 branches in a typical single family house. --- Quote from: james_s on October 26, 2019, 04:56:16 pm ---Voltage conversion is cheap and efficient now so it can be done at the point of use when needed. Less copper, lower losses, lower cost, there are lots of advantages. But not really enough to change it at this point, 120V works fine. --- End quote --- More electronic waste. |
| vad:
--- Quote from: Simon on October 26, 2019, 08:44:46 pm ---litres per 100km alwoys confused me. I mean why? --- End quote --- I am more confused by MPG-e ratings of EVs that don’t have petrol tank. |
| Monkeh:
--- Quote from: vad on October 26, 2019, 10:01:26 pm --- --- Quote from: james_s on October 26, 2019, 04:56:16 pm ---Have you looked into the cost of 10AWG wire or calculated the losses you'd end up with? --- End quote --- Yes, I did few messages above. I’ll spare you from searching. 1.5V voltage drop (11% power loss at 12V at receptacle, 6% power loss with 24V at receptacle). And that’s at maximum load at furthest distance. I doubt AC-DC converter in a typical A19 LED bulb has near that efficiency. 250ft roll of 10/2 Romex is $130 at the nearest Home Depot. 12/2 is $60, 14/2 is $40. You need 3 rolls to wire 10 branches in a typical single family house. --- End quote --- Or you could use a tiny fraction of the copper, existing hardware, and have greater flexibility and no single point of failure for all your lighting, and probably still come out on top on efficiency.. Even if you do fall slightly behind, substantially less copper used, no single point of failure, no DC rated switching arrangements, no separation of ELV and LV wiring needed. Oh, and you won't need terminations suited to ludicrously large wiring either. |
| vad:
--- Quote from: Monkeh on October 26, 2019, 10:16:14 pm --- --- Quote from: vad on October 26, 2019, 10:01:26 pm --- --- Quote from: james_s on October 26, 2019, 04:56:16 pm ---Have you looked into the cost of 10AWG wire or calculated the losses you'd end up with? --- End quote --- Yes, I did few messages above. I’ll spare you from searching. 1.5V voltage drop (11% power loss at 12V at receptacle, 6% power loss with 24V at receptacle). And that’s at maximum load at furthest distance. I doubt AC-DC converter in a typical A19 LED bulb has near that efficiency. 250ft roll of 10/2 Romex is $130 at the nearest Home Depot. 12/2 is $60, 14/2 is $40. You need 3 rolls to wire 10 branches in a typical single family house. --- End quote --- Or you could use a tiny fraction of the copper, existing hardware, and have greater flexibility and no single point of failure for all your lighting, and probably still come out on top on efficiency.. --- End quote --- Unfortunately, I still have to come across AC-powered A19 LED bulb that can work reliably in fully-enclosed or semi-enclosed luminaries (up to promised 25,000+ hours MTBF, without intermittent thermal shutdowns or bricking itself). And I still have to come across AC-powered A19 LED bulb that can dim properly. |
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