A Short Guide to Vintage Traynor Amps | Circuit Breaker Parts

Pedantic FWIW: Afghanistan and North Korea and some banana nations use 110V. USA uses 120V/240V. Japan is the oddball, using 100V. Annoying because you can’t draw more than 1 kilowatt from a socket there (kettle, hair dryer, space heater…). And having lived with the three voltages (100V, 120V, 240V) on four continents, I’ll happily take the 120V supply instead of the 240V.

Yup. Isolation is important as other commenters have noted. I’d compare electric heating pad design too, and probably require a door interlock to cut power to the bed when the door is open (enclosed only). A simpler way may be to simply put a transformer or “dirty” switcher under the bed and not put the higher voltage into the build plate in the first place. Use either a digital on/off for the switcher or a ZVS SSR for the transformer high side control. Would a 1/100 or 1/120 of a second minimum duty cycle and lsb affect the temperature that much, given the thermal mass of the system?

All of this, if you suppose that you are taking a full hand of cable. Got shocked a few times with AC (and DC as well) and since I was just thouching, not handling, I had no trouble to get away with it (just swearing A LOT and throwing my screwdriver through the room).

Sources: licensed mechanic-level electrician Joe Amato; licensed master electrician Johnny Goudie, owner of John Goudie Electric in White Plains, Maryland; master electrician and electrical contractor Al Hildenbrand, owner of Al’s Electric works in Minneapolis, Minnesota; Dmitri Kara, senior executive of London-based Fantastic Handyman

Quite often, when I was in the Air Force as a Cable Dawg, I would get zapped while doing copper cable cut splices for mission critical systems. Meaning they were left powered and came back on one by one as they were spliced. -48v DC is very tingly when it runs through a crimper and into your arm…

One of the most important rules ever: “Never underestimate your own stupidity.” Knowing perfectly well how to safely power down a circuit / appliance / machine is sadly not sufficient to actually do it, especially so if it has become a repetitive task and there are elements of distraction. If ones life is at stake, there should be check-lists written in stone, just like in aviation.

All of these ratings can be found in NEC (NFPA 70) Table 310.15(B)(16) in detail, but as an example, according to this NEC chart, a 6-gauge copper circuit rated at 90°C (194°F) has an ampacity of 75 amps while a 6-gauge aluminum conductor rated at 60°C (140°F) has an ampacity of 40 amps. Of course, there are other considerations in addition to this, but it is clear the rules of thumb we often use can get us in trouble if we aren’t aware that exceptions exist and what those exceptions are.

厦门仲鑫达自动化设备有限公司是一家专业从事全球知名品牌（DCS系统）（机器人系统）（大型伺服控制系统）模块 备件销售,公司产品内容为分布式控制系统(DCS) 、可编程序控制器(PLC)、 MOTOROLA MVME工业用模组 、工业控制通訊转换器(Anybus) 、远端输出/输入模块(RTU) 、工业电脑(IPC)、 工业用低頻萤幕(IPC) 、人机界面SCSI(50、68、80Pin) AnyBus(Gateway)现已成一家全球性的工业自动化备件及零部件的销售企业。

So far we have discussed your bench and associated equipment. We are not however quite done though, because there is one final component in keeping your bench safe: you. If you have a piece of equipment in front of you and you are about to open it up, the most significant part of your safety routine doesn’t lie with your equipment, but in how you approach it.

However there is a snag. In recent years there has been a flood of cheaper instruments arriving on the market, and some of the manufacturers of these devices have been found to put IEC 61010 ratings fraudulently on items which do not in any way meet those standards. We have covered tales of dodgy cheap multimeters and test failures more than once here at Hackaday, unfortunately this is a widespread problem. So please bear this in mind when buying a multimeter or other instrument for use with mains voltages: the cheapest may not be good enough. We have all used £5/$10 bargain meters with our low-voltage analogue or microcontroller work because a flashing LED on a breadboard is hardly hazardous, however for higher voltages those IEC class markings have to come with a believable provenance. Buy the most expensive instrument you can afford from a decent and reputable manufacturer, it’ll keep you safer and you’ll get a top-quality meter that will last you a lifetime.

I haven’t seen you around the traps here before and you have put in a good effort so welcome aboard.

https://www.ul.com/newsroom/publicnotices/ul-warns-of-solid-state-relay-with-counterfeit-ul-recognition-mark-release-13pn-52/