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Ivan Vegvary <ivanvegvary@gmail.com>: Nov 03 10:38AM -0700 Thank you everybody. Great help! Will always use the isolation xformer

Cursitor Doom <curd@notformail.com>: Nov 03 06:38PM On Sat, 03 Nov 2018 10:38:54 -0700, Ivan Vegvary wrote:   > Thank you everybody. Great help! Will always use the isolation xformer   One last thing: don't ever get into the habit of using that variac of yours as a convenient substitute for an extension lead. Enjoy!         -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

tabbypurr@gmail.com: Nov 03 11:56AM -0700 On Saturday, 3 November 2018 15:05:48 UTC, Fox's Mercantile wrote: > difference.   > Primarily, it was done from a "Is this the cheapest and easyist (also > cheapest) way to do it this way?"   It makes a huge difference. Fuse in live blown: faulty equipment is now dead. Fuse in neutral blown: faulty equipment looks dead but is live. One can electrocute you after a live to case fault, the other won't. This is why UK banned dual pole mains fusing in 1955.     NT

Phil Allison <pallison49@gmail.com>: Nov 03 08:13PM -0700 Ivan Vegvary wrote:   > Thank you everybody. > Great help! Will always use the isolation xformer   ** Who here said to do that ???   Good safety practice is to use an isolation ONLY when you need to - as with old live chassis radios or off-line SMPUs.   Never disconnect your scope from safety earth and if equipment on test has the safety ground connected to the chassis - leave it that way.       .... Phil

Ralph Mowery <rmowery28146@earthlink.net>: Nov 03 11:58PM -0400 In article <839ff2eb-6ef5-4f76-aae9-18bf09ede457@googlegroups.com>, tabbypurr@gmail.com says... > Fuse in neutral blown: faulty equipment looks dead but is live. > One can electrocute you after a live to case fault, the other won't. > This is why UK banned dual pole mains fusing in 1955.   Ideas and codes change from one country to the next and sometimes even in the same country.   In my opinion one of the worst things was some equipment where aI worked. The standard in the US was that on electrical equipment boxes red was off and green was on. We got in some equipment from Europe and they used Green for off and Red for on. The reason being that Green was safe to open the door and red ment power was on and danger.     I know that in a series circuit that electrically it does not matter in which order things are for them to work. I was just courious that much of the older two wire 120 volt stuff that has a transformer , the power comes in, then a switch, transformer primary , fuse and back out to the power. I would have thought it would be the power, fuse, switch, transformer and back out to power.

tabbypurr@gmail.com: Nov 04 01:29AM -0700 On Sunday, 4 November 2018 03:58:17 UTC, Ralph Mowery wrote: > comes in, then a switch, transformer primary , fuse and back out to the > power. I would have thought it would be the power, fuse, switch, > transformer and back out to power.   The only justification I can think of for the old practice of putting the switch & fuse in different leads for unpolarised kit is the idea that the switch is a relative weakpoint, so would likely act as a higher current fuse if there were a short from live to some good earth - not good but better than nothing. I suppose it's also marginally easier for production to have 2 things to solder the mains wires to.     NT

Cursitor Doom <curd@notformail.com>: Nov 04 10:41AM On Sat, 03 Nov 2018 23:58:08 -0400, Ralph Mowery wrote:   > red was off and green was on. We got in some equipment from Europe and > they used Green for off and Red for on. The reason being that Green was > safe to open the door and red ment power was on and danger.   And just to further complicate matters, in domestic consumer units nowadays, the spur is live when the switch is in the 'up' position and 'off' is down. This is arse-about-face to what I - at least - was brought up with in the UK. :(         -- This message may be freely reproduced without limit or charge only via the Usenet protocol. Reproduction in whole or part through other protocols, whether for profit or not, is conditional upon a charge of GBP10.00 per reproduction. Publication in this manner via non-Usenet protocols constitutes acceptance of this condition.

Ralph Mowery <rmowery28146@earthlink.net>: Nov 04 10:53AM -0500 In article <prmice$bk8$3@dont-email.me>, curd@notformail.com says... > nowadays, the spur is live when the switch is in the 'up' position and > 'off' is down. This is arse-about-face to what I - at least - was brought > up with in the UK. :(   I live in the US. I don't know if it the code or not, but just about all the light switches and many other types that work up and down, the up is on and the down is off.   From what I have heard in the UK up is off and down is on for house light switches.   I only have a couple of things around the house that have vertical switches. The ones from China are up for on, but one from Japan is down for on. Most everything else is push button and that is push in for on if the switch stays in. On some the pushbutton just returns to the out position.

RION <caedfaa9ed1216d60ef78a6f660f5f85_13638@example.com>: Nov 03 11:14PM replying to Ryan, RION wrote: Well, here it is 2018, and I am having a similar problem with an 8,000 BTU window ac. I guess I should feel luck that mine does go down to 65.7 F. The problem here is that I bought this to cool a wine cellar. The ac unit is in a fake window between two parts of my basement. The wine cellar part is well insulated, but you can't get 60 F (the temperature I really desire) if the calibration on the thermistor is wrong. I am getting ready to use a fixed resistor along with a pot, and hope I get lucky.   -- for full context, visit https://www.homeownershub.com/maintenance/re-adjustiing-mod-ing-digital-thermostat-on-lg-window-air-c-1144161-.htm

bilou <padepub@free.fr>: Nov 03 07:32PM +0100 Tim R avait soumis l'idée : > seconds, I haven't tried measuring yet.   > We've been discussing this on another forum. Why would there be a delay? > It's not unique to mine, either, others have noticed similar results.   To start the switching control IC needs a 12V supply. The only low cost way to get it is by slowly charging a capacitor from rectified mains through a rather big dropping resistor. After start a special transformer winding takes care of the 12V. If the LED lamp can be used on both 120/240 VAC start must be much slower with 120V. Here in France I never really noticed the problem. On the other hand,normally off lamps, sometimes blink slowly in the dark because of capacitive coupling of the wiring around the switch.

Look165 <look165@numericable.fr>: Nov 03 09:13PM +0100 the cap is useless.   Just make sure you have a rectifyer bridge instead than a simple diode as rectifyer.   think od half sine and double sine feed.       Tim R a écrit :

John-Del <ohger1s@gmail.com>: Nov 03 09:58AM -0700 > I've used 2 lots of cinema equipment from the 1930s. The small setup was reasonably safe, the full size one was another matter. Safety was not high on the list of concerns of whoever designed it, and it was top quality equipment (Kalee). If you opened the side of the thing and caught a glimpse of the carbon arc you wouldn't be seeing anything for a while. There was no latch, let alone a lock or interlock. Needless to say one needed to open the thing regularly to do the job.   > There was also no easy way to check if the extractor fan was removing the arc combustion products, and of course no monitoring or interlock and no other vents etc. There were also zero precautions available for nitrate film. And lots of mercury in the rectifiers. The projection booth was all fireproofed though - but the fire extinguishing equipment totalled a single 1kg chemical extinguisher. A cap that might have killed someone that messed with it without knowing what they were doing would not have raised any concerns.   > NT   Wow. Hopefully, only those trained to service that equipment would have worked on it.

tabbypurr@gmail.com: Nov 03 11:53AM -0700 On Saturday, 3 November 2018 16:58:17 UTC, John-Del wrote:   > > There was also no easy way to check if the extractor fan was removing the arc combustion products, and of course no monitoring or interlock and no other vents etc. There were also zero precautions available for nitrate film. And lots of mercury in the rectifiers. The projection booth was all fireproofed though - but the fire extinguishing equipment totalled a single 1kg chemical extinguisher. A cap that might have killed someone that messed with it without knowing what they were doing would not have raised any concerns.   > > NT   > Wow. Hopefully, only those trained to service that equipment would have worked on it.     No-one got any training, and there was no paperwork relating to the equipment/installation. No-one checked what we did. We did all have an electronics background though, so weren't stupid with it. I used to check the extractor fan was running, but it wasn't easy to tell if it was. One other chap never bothered to, and the 3rd guy checked it very occasionally. It was once found to be jammed but they still showed the film, so I guess arcs aren't too bad with CO. There was no CO2, CO or smoke detector, no fire drill etc. Times change.   The kit was so old I don't know if they'd have found anyone else to service it. Kalee projectors live in museums now. https://www.google.com/search?q=kalee+projector     NT

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