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The Regular Stuff: Chat, Buy, Sell, Off Topic, etc. => Off Topic => Topic started by: Jim on October 06, 2020, 05:51:54 pm

Title: Re: Multimeter question
Post by: Steam Technology on October 06, 2020, 10:36:08 pm
Jim, the motor you have will deliver dc volts, you have the meter on ac vots and digital meters give strange readings with dc on ac scale.
The motor should give 11 to 12 volts dc at 2500 rpm.
On your meter 20v dc would be good, from the off position 3 notches or scales turning to the right.

I did not notice the leads as i looked at what Jim asked .
But i think his generation will be AC and not DC  A rectifying bridge will be needed for DC .
 Simple test . Put output to a LeD. And turn slowly ,it should flicker.
Reverse leads and try again and it should still flicker .
If so it is AC and LeD is only using half of power generated.
If it only goes in one direction then it will be DC generated
They are mosrly all pm motors Scorp, so will deliver dc not ac, except any stepper motors which deliver a form af ac depemding on how the coils are interconnected.
Title: Re: Multimeter question
Post by: Scorpion2nz on October 06, 2020, 09:25:18 pm
Jim, the motor you have will deliver dc volts, you have the meter on ac vots and digital meters give strange readings with dc on ac scale.
The motor should give 11 to 12 volts dc at 2500 rpm.
On your meter 20v dc would be good, from the off position 3 notches or scales turning to the right.

I did not notice the leads as i looked at what Jim asked .
But i think his generation will be AC and not DC  A rectifying bridge will be needed for DC .
 Simple test . Put output to a LeD. And turn slowly ,it should flicker.
Reverse leads and try again and it should still flicker .
If so it is AC and LeD is only using half of power generated.
If it only goes in one direction then it will be DC generated
Title: Re: Multimeter question
Post by: Nick on October 06, 2020, 09:09:53 pm
Having some fun in the shed that's for sure and passing a rainy day.

Don’t forget to get some video of your testing, I want in on the fun  ;)
Title: Re: Multimeter question
Post by: Jim on October 06, 2020, 09:07:52 pm
Thanks Jasper and Dave, appreciated guys.

Ok with that multimeter setup correctly I'm now getting around 7.5

Having some fun in the shed that's for sure and passing a rainy day.
Title: Re: Multimeter question
Post by: Steam Technology on October 06, 2020, 08:47:11 pm
Yes Jim that is now correct.
A good selection of motors, some good, some not so good. Running them up using the meter will tell you what is what.  Try to keep the revs the same so readings are comparable.
Title: Re: Multimeter question
Post by: J.Jackson on October 06, 2020, 08:01:02 pm
Ah!
Generation is a fun path to trod down.
I occasionally try and match an era of a steam engine to belt to an old little toy motor {example 1950’s Jensen with a 1950’s toy motor to power a 1950’s small “thing”}
My additional amateur advice is to start out with a basic cheap analog meter too. Those digital meters can sometimes have quirks that can confound a new guy doing what your trying to do.
Steam Technology correctly points out the way to go with your digital meter.

Ps...  many meters can have an internal battery and a little fuse that may need to be replaced over time , or they can cause fits.
Title: Re: Multimeter question
Post by: Jim on October 06, 2020, 07:58:30 pm
Thanks Dave I've changed what you said (haven't tried to run the motor yet) -

[attachimg=1]


These are the motors I'm mucking around with -

[attachimg=2]
Title: Re: Multimeter question
Post by: Steam Technology on October 06, 2020, 07:45:14 pm
Jim, the motor you have will deliver dc volts, you have the meter on ac vots and digital meters give strange readings with dc on ac scale.
The motor should give 11 to 12 volts dc at 2500 rpm.
On your meter 20v dc would be good, from the off position 3 notches or scales turning to the right.

 Having looked again your leads are in the wrong place. The black lead should be plugged in to the com terminal far right.
The red lead should be in the middle terminal V ohm mA.
Title: Re: Multimeter question
Post by: Steam Technology on October 06, 2020, 07:40:44 pm
Jim, the motor you have will deliver dc volts, you have the meter on ac vots and digital meters give strange readings with dc on ac scale.
The motor should give 11 to 12 volts dc at 2500 rpm.
On your meter 20v dc would be good, from the off position 3 notches or scales turning to the right.
Title: Re: Multimeter question
Post by: Jim on October 06, 2020, 07:01:27 pm
Thanks Dennis and Jasper.

I have a motor out of a printer and have hooked it up to that setting on the mutimeter and spinning the motor on a drill I'm getting around 150 - 156 readout.

Just want to know what the 150 - 156 actually is.

Thinking of using the motor as a genny for a steam engine accessory.
Title: Re: Multimeter question
Post by: J.Jackson on October 06, 2020, 06:58:03 pm
I would hazard a guess And say max 200 Volts AC  next step up would be max 500 volts Ac
And i think  the next scale above would be volts DC ?
Scorpion is on track.
Jim, what are you trying to meter ?
https://www.garagetooladvisor.com/electrical/multimeter-symbols-their-meanings/
Title: Re: Multimeter question
Post by: Scorpion2nz on October 06, 2020, 06:51:03 pm
I would hazard a guess And say max 200 Volts AC  next step up would be max 500 volts Ac
And i think  the next scale above would be volts DC ?
Title: Multimeter question
Post by: Jim on October 06, 2020, 05:51:54 pm
Multimeter question .....yes, I am electrically and electronics challenged and I admit it :)

Is what I have indicated below the setting for Volts?

[attachimg=1]