The last discussion on electricity we had was 6th grade. Field trips to ford, the Guthrie theater, General Mills were important but wish i would have had cooking.
2 Likes
That’s debatable 
I know lots of men that would have benefited greatly from cooking class versus literature. It doesn’t help to recite Shakespeare while munching on McDonalds. Of course, back then you probably would have gotten beat up when other kids found out 
2 Likes
We were fortunate to have many industrial arts opportunities including “electricity”. Unfortunately, many of the kids in that class knew more than the instructor. We spent a lot of time getting into trouble once the established curriculum was completed. Plus, everything was analog back then. That’s a sideways eight, not a zero!
i would not have been one of those kids.
I was clueless back then, and know nothing about anything. I tried to watch NFL with my Dad way back when, and didn’t understand why only one team had a quarterback on the field at a time.
My grade school years were spent in defensive mode, wondering when the next slap would come, and from who. My hearing was worse then than it is now.
My prime money-earning years, twenties through forties, were wasted, with no career direction, hopping from job to job to job, low-paying ones at that.
Now, at 55, I want to go back and avenge all that, by going into fields that, while I have no experience, I have better awareness and have since burst out of my social bubble.
Lots of options out there. Had to call the pest control guy for a bat problem. Amazing guy. Said he had a reading disability but has his clerk read everything for him. Part time stunt man but his pest business runs all the way to Ohio from Minnesota. Found his nitche.
Gotta try to crank up my pressure washer. Reading diections. Looks like last used in 2021.
Allow me to put this in perspective. If you have a container that is open to the atmosphere, it has 14.7 psi of air pressure in it. That is because the atmosphere at sea level is 14.7 psi. If you capped it off and drew a perfect vacuum, the absolute pressure in the container would be 0 psi. Now you add air until the absolute air pressure is 29.4 psi, you twice the atmospheric pressure in the container compared to what is on the outside. The inside is 29.4, but a typical tire gauge which uses atmospheric pressure as a reference only measures 14.7 psi. So you added the air to the container, you went from -14.7 psi to + 14.7 psi.
Now let’s look at the container. The container may have a working pressure of 100 psi, that is the highest pressure expected for the tank during its normal and intended use. It will also have a max pressure that should not be exceeded at any time, it may be 200 psi. So 200 psi would be it’s class, well above the expected max. In addition, to attain this max pressure, samples, or in some cases, all the containers must be tested to burst pressure, in this case might be 1200 psi to insure the tanks safety for its expected life span. If it passes this test, it is good to go.
So split phase 240v means that there are two AC voltages of 120 volts, one on each hot wire that when one goes +, the other is going -. The difference is +120 minus -120 + 240V. The wire are tested to various voltages using various tests that gives the insulation on the wires a rating of 600 VAC (voltage alternating current).
Wasn’t Home Economics available as an elective for your age group? In my age group Mpls Schools had wood shop, metal shop, print shop, and electrical as mandatory classes for 7&8th grade boys. Advanced classes became electives 9-12th grade. Girls had Home Ec. A coworker’s husband broke the gender barrier and got into Home Ec, but he did it to meet girls. Unfortunately my HS did not have auto shop, so my training was OJT, the other guys at the Mobil Station went to North High which did have auto shop.
BTW, the Guthrie Theater was usually enjoyable, for my age group, always Shakespeare, though Romeo and Juliet set in Antibellum America, Shakespearean English with southern accents did not quite work for me.
Mentioning auto shop got “Car Talk” subject credit😀
That sure beat “symbolic interpretation of Shakescrap” as part of highschool English…!
As far as OJT (on the job training?) is concerned? That’s anathema to most employers nowadays. They want folks coming into a field with 5 years experience, and you’ve got the proverbial dog chasing its tail of job > experience > job experience infinite loop.
H e c k I’d be willing to work two weeks, for free, to prove to some employers I know my stuff enough to do the job.
Yeah accents are interesting. A German with an English accent. But that’s show biz provided by a particular segment of the population.
We had wood, metal shop, and drafting in jr high. Home ec was just for girls. Once you hit 9th grade, there was no more time for shop if you were on a college prep course. I got my shop training from summer jobs an$ electronic in th3 army. Not to discount friends.
I forgot drafting! We may have still called it “mechanical drawing”.
This was the 60s, my main job was pumping gas. Work was gender oriented, McDonalds only hired males! Girls in my class worked as waitresses or cashiers. The evening shift at our local “malt shop” was almost entirely composed of girls from our class. The boys worked at gas stations, McDonalds, or the car wash. As soon as I turned 18, got a factory job laying up fiberglass boats in spite of holding a 1-A draft card, jobs were so plentiful I went through three different employers in unrelated jobs during my year before I dodged the draft by enlisting.
I still remember the guy criticizing the way I wrote my “G”. I always put a line in it like the German 7, to distinguish it from a six. Still do.
My father did that during WWII. He got a draft notice from the Army and enlisted in the Navy instead.
My draft status was 4A and I wasn’t going until DoD recalled veterans. I figured we’d all be cinders from nuclear blasts before I was called up and felt safe. Kinda. I turned 18 in the summer of 1970 and I doubt that I would have gone to Vietnam since troops were coming home. It would have been 1971 before my deployment after training. Anyway, despite a lottery number of 96 during a year when they called up men with lottery numbers up to 108, I wasn’t going anywhere.
It still is. After 20 years of job-hopping, the only place that would hire me was donated goods retail. While working there, I interviewed for the type of office work I did for temp agencies after graduating college - office/clerical.
I interviewed and interviewed and interviewed. Did everything right - suit and tie, neat resume, no chewing gum, eye contact. Got that letter in the mail but never the job.
When I checked later on to see who the jobs went to, it was always a woman.
Technically it should briefly show 170V, and -170V but it can’t react quickly enough for that. The average DC voltage of an AC supply is 0, so the meter will show some numbers that are jumping around that are close to 0. If you rectified the AC supply to DC with diodes and measured that it would show 170.
Yes, the “average responding sine wave calibrated” RMS AC meter. It measures the average rectified AC Voltage, which is different from the true RMS Voltage. Then the reading for the average AC Voltage is multiplied by a correction coefficient to show you the RMS Voltage, for a sine wave. This correction coefficient assumes that the AC wave form is a pure sine wave. So the meter will not measure accurately on anything other than a pure sine wave, unless you divide away the correction coefficient and use it as an average AC Voltage meter.
We have True RMS meters that do provide an accurate, true RMS value. They are expensive and not of interest to the casual user.
Since you understand this concept, here’s a story you may find interesting. At work, we provide equipment used in semiconductor manufacturing. A scan amplifier is used to control the ion implantation beam that is scanning the wafer and inserting single ions at a time into specific locations on the wafer- doping the wells. The beam control voltages swing +/- 50kV at a slew rate of up to 800V/usec. As you can imagine, the waveform is not a linear progression or symmetrical as throughput is everything in this business and so getting to the next implant location as fast as possible is paramount. The customer insisted we provide an RMS value for a feedback signal on the controlling waveform. No amount of “discussion” could dissuade them from this requirement. So we developed the (expensive) hardware solution to produce this output for them. Later, we found out they didn’t even use it- it was a useless feedback. Gee, who would have thought?
Back to cars, a $15 meter will suffice for car repair unless you want to start diagnosing issues with the CAN bus signals or something more esoteric…
1 Like
Yes, that’s true, but also remember it’s more and more common to find close to 400 volts in the HV system of hybrids and EV’s.
And remember a meter is only as good as the leads being used. Test leads are a wear item, especially in automotive. They get slammed in doors, run across hot engines, tangled in knots. My pet peeve is tightly wrapping leads around a meter like you’re winding a coil. No wonder they go open circuit. When I’m done with my leads they get loosely coiled into one loop and put in the cart drawer for next time.
1 Like
What’s your point? Even the cheapest DVMs can go higher than that. First one that showed up on Autozone web site-
The leads are rated for the voltage range specified on the meter. If you want to exceed the meter native range, you need a HV probe accessory.
Do auto techs routinely mistreat their other tools? Do they throw their expensive impact on the floor? Every tool has certain limitations regarding the level of abuse it can sustain without breaking.
Used professionally, you probably have a more expensive meter. They typically come with silicone jacketed leads that are extremely tolerant of abuse and hot/cold weather use. I probably have 6 or 7 high quality meters. I still have my very first analog meter from Radio Shack and it works properly, original leads!
Sounds like you are very careful with your meter- something I would expect based on your postings here. It’s true, many people are not so diligent and then they pay the price later having to buy replacement parts or equipment. I tend to watch carefully to see if people exercise care before I will lend them my tools. I have a small cadre of friends that have carte blanche for borrowing and others that are verboten 
I can understand 400VDC seems like a lot if you’ve never been exposed to working on those kind of voltages. I started my career as an Electrical Engineer designing and building industrial mains powered equipment- 480VAC 3 phase. Been shocked by it too. These days, our low voltage lab has similar inputs, 500VDC bus cap supply and outputs below 10kV. The high voltage lab can go up to 750kV so the car stuff is no big deal for me. Sometimes I forget that this could be intimidating for others not accustomed to it…
Where I live in NC there’s a guy who is very good at starting up restaurants/bars. One of his places is located at a golf course. All of his waitresses and bartenders are female.
But another place is a sports bar and he has both female and male servers. For him it’s just the type of place it is. When guys come off of the golf course they want a female taking their order. Sorry if that sounds sexist.
The sports bar is a large place, it was originally built as a “■■■■■■■”. Remember when a male tried to get hired as a waitress there? It was national news.The guy sued ■■■■■■■ and lost! Can you imagine a bunch of guys going to ■■■■■■■ and a guy shows up at their table? I think the Judge agreed!
Edit: Oh geeze! H-o-o-t-e-r-s. Can you believe that word is censored?
What systems require up to 750kV power, and at what amperage?