Analog frequency meter

[colum]

Hello,

When you resize the pictures to have a size of about 300 kB, you will be fine.
You can add the pictures to a post using the "Upload a File" button.

Bertus

Hi bertus. One more question. When I send these photos do I forward them to your original response or to the last photo (mine) uploaded. I just want to make sure you see them, I'll need some advice.
One of the contact meters have a Hz scale in the 20s is this an old RR scale..Thanks...colum

 

[bertus]

Hello,

I do see your pictures.
I don't know the RR scale, perhaps it is the rotation rate.
Here I found some pages about the working principe of the vibration meters:
https://www.yourelectricalguide.com...sists of a,is wound around it as shown in fig.
https://www.aboutcircuit.com/mechanical-resonance-frequency-meter/

Bertus

 

[colum]

Thanks for the excellent articles on meters.
As suggested before the non electrical physical contact meters could register vibrations in bad bearrings etc
I am going to see if it works on AC and DC motors and if so then its the rotating armature and if its only the AC then I assume its the electrical field.. I assume many things mostly incorrectly... Thanks...colum

 

[bertus]

Hello,

There will be analog vibration meters without the electical excitation.
The mechanical movement of the vibration of the to be measured object must be able to reach the reeds to show the frequency.

Bertus

 

[poor mystic]

Ohh those are for getting a generator to run at the right speed. They're a bit like a mechanical tuning fork.

 

[colum]

Hi poor mystic. The tuning fork analogy is interesting so in that case the signal is transmitted to the motor body by the rotating rotor and the vibrations of the heavy rotor is sensed by the meter.
I wonder what the official name of this meter is.
I don't think I have a motor fast enough to do a test...Thanks...colum

 

[bertus]

Hello,

In the article I posted they call it a "Vibrating Reed Mechanical Resonance Type Frequency Meter".

Bertus

 

[colum]

Hi Bertus. I may have missed it but it seemed that those meters were electrically powered where the contact only meter may have a different name that I could look up.
Oddly I have a tuning fork that has electric coils on both forks no idea what it does....colum