DC Voltage Output

[Hammermechanicman]

When something with a battery comes in the shop i use an internal resistance type tester to find the health of the battery. Then i clean battery connections and start the equipment and run it up to about 3000 rpm and check voltage at battery to see if it is charging and then turn on any accessories like cluth and lights and measure voltage at batter for charging voltage. If it has about 13.5v or better i call it good and move on to other maintenance. I am sure the internet will tell me i am wrong but i try to not over think a lawn mower charging system. Don't really care if it is peak to peak, RMS or average volts. My meter is a true RMS meter but doesn't matter all that much.

 

[StarTech]

When something with a battery comes in the shop i use an internal resistance type tester to find the health of the battery. Then i clean battery connections and start the equipment and run it up to about 3000 rpm and check voltage at battery to see if it is charging and then turn on any accessories like cluth and lights and measure voltage at batter for charging voltage. If it has about 13.5v or better i call it good and move on to other maintenance. I am sure the internet will tell me i am wrong but i try to not over think a lawn mower charging system. Don't really care if it is peak to peak, RMS or average volts. My meter is a true RMS meter but doesn't matter all that much.

That basically all we need to; unless, we designing a new system. It nice to know how they got there but normally all we to know is a system is operating within the design specs which in this case the 2-4 amps regulated spec. Now the output ampere can boosted a little by installing a regulator but not worth the expense of regulator; unless, you install the higher amperage stator in the first place. Otherwords beef up the charging system.

Besides over thinking things can give you headaches and I don't need to add to my normal weekly headaches.

 

[Telesis]

I couldn't agree with you guys more! The simpler the better which is what I described(as you and others have) in post 14! However, the engineer in me finds it hard to ignore posts that contain untruths and/or misunderstandings. I treat these forums not only as a way to solve an individual's specific problem, but also to help others understand.

As I was taught in engineering school 40+ years ago... "Facts Are Our Friends!"

Enjoy!

 

[Hammermechanicman]

As I was taught in engineering school 40+ years ago... "Facts Are Our Friends!"

Enjoy!

I always thought it was "don't cloud the issue with facts"
Always fun watching a newb tech using a meter.

 

[Telesis]

Just like some folks with calculators..... 3.141592654 has to be the answer...'cuz the calculator says so'. I tutor high school kids in math and can't tell you how often this occurs these days!

We had a Senior Vice President at the automation company I worked for stand up in front of a large group of employees and open his presentation with "I want to start my presentation by saying I am unencumbered by the facts!" Funniest darn thing I'd heard from a SVP my entire career! LOL!

 

[bertsmobile1]

Yes there is a sharp cut off between the log tables / slide rule students , the calculator students & the computer students.
We had a physics professor who would put up an equation then promptly round every number up or down to the nearest 10 so we could do the maths in out heads
When some of the students complained about his technique his reply was
"I am trying, with very limited success to show you the how & why , the actual numbers are not important right now.
When you are sending a rocket to Pluto you can worry about the decimal places "

Then there was an engineering tutor who would fail any student who used too many decimal places in an answer .
Most of his problems would have a coarse dimension like 2' so any answer with a greater implied precision of 1/2 foot would be marked as a fail .

I was have a chat about this a while back with a friend.
I have noticed that for some reason all of the mower specs for torque are now in in.lbs which of course implies a precision of +/- 0.5 in.lbs
But the actual tollerances have not changed since they were noted in ft.lbs
I presume this is because of the advent of digital torque wrenches as very few mechanical ones are marked in in.lbs except some micrometer scale spring loaded ones which of course are the least accurate wrenches in the first place.

 

[txmowman]

Well trying to explain this is going to be well over the heads of most. Plus it take several days of reading on my part to fully familiarize myself with the formulas (heck it been 40+ yrs since I knew these by heart.) But I do have my ARRL manuals on the shelf for reference

But txmowman your understanding of rectified DC circuits is lacking. Even your theory is off several volts. You got RMS voltages being converted to pulsing DC voltage ((0V to peak (RMS - rectifier voltage drop). First you must consider peak AC voltage, voltage drop the rectifier, the capacitance in the load, along with other factors.

Here is an example of what is actually at your 120 vac wall plug. It varies from zero to about 170v peak (or about 340 volts peak to peak) 60 times a second or 50 times a second outside the US. This why it can easily kill you along the amp capacity.

The reason Briggs don't give a voltage rating is that an unregulated DC circuit voltage is quite varied depending a which factors are present at the time of the voltage measurement.

Whatever, lol. You hacks on these forums are a joke. If you think it is any more complicated than what I explained, is only puffing your shallow ego.

 

[Hammermechanicman]

Yes there is a sharp cut off between the log tables / slide rule students , the calculator students & the computer students.
We had a physics professor who would put up an equation then promptly round every number up or down to the nearest 10 so we could do the maths in out heads
When some of the students complained about his technique his reply was
"I am trying, with very limited success to show you the how & why , the actual numbers are not important right now.
When you are sending a rocket to Pluto you can worry about the decimal places "

Then there was an engineering tutor who would fail any student who used too many decimal places in an answer .
Most of his problems would have a coarse dimension like 2' so any answer with a greater implied precision of 1/2 foot would be marked as a fail .

I was have a chat about this a while back with a friend.
I have noticed that for some reason all of the mower specs for torque are now in in.lbs which of course implies a precision of +/- 0.5 in.lbs
But the actual tollerances have not changed since they were noted in ft.lbs
I presume this is because of the advent of digital torque wrenches as very few mechanical ones are marked in in.lbs except some micrometer scale spring loaded ones which of course are the least accurate wrenches in the first place.

Somewhere in the barn i still have my old slide rule. Haven't used it since high school. Probably forgot how to use it by now. It is probably in the same box as my drafting board T square and triangles and french curves also not used since i found Sketchup. I think i threw out the Heathkit VTVM i built. Us old hack dinosaurs are fading away. Funny thing is i have a friend in his 20's with a degree in electrical engineering specializing in controls and he has me do electrical work on his house. You don't need a torque wrench any more. Just tighten till your bad elbow clicks.

 

[Scrubcadet10]

Whatever, lol. You hacks on these forums are a joke. If you think it is any more complicated than what I explained, is only puffing your shallow ego.

Star is a little more than a hack. Forums are public place so you often times won't see opinions you agree with.
Ask 100 people the same question, you'll get 99 different answers.

 

[Telesis]

C'mon Hammer, it's like riding a bike....multiply two numbers using the C and D scales! Mine was the last engineering class in 1976 that the "slip-stick" was taught....a time when the TI SR-50 was the coveted dream machine calculator!

For the record txmowman, nobody is 'puffing their shallow ego.' We're just trying to set you straight. Take the feedback in the spirit in which it was intended, to educate. I realize it's hard to admit that your understanding of a topic is flat out wrong, on multiple levels. I guarantee you every one of us has done so here or elsewhere. But to sit there and insist that 2 x 2 = 5 and we are the 'hacks' for informing you it's really 4 speaks volumes, especially after you were provided with the technical sources right from B&S so you wouldn't have to take our word for it!

I still wish you a Happy New Year!