ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
220/230/240V 60Hz Systems
by gfretwell. 09/23/18 02:50 PM
Inspection camera help
by petey_c. 09/22/18 07:52 AM
Motion detectors and dimmers
by gfretwell. 09/20/18 04:02 PM
Extension cords
by annemarie1. 09/20/18 08:54 AM
Acronis Backup 2017
by gfretwell. 09/16/18 12:46 AM
New in the Gallery:
Plug terminals
Housebilding DIY wiring
Who's Online Now
1 registered members (ghost307), 33 guests, and 20 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Audible Hertz #127521
08/13/01 04:47 PM
08/13/01 04:47 PM
S
sparky  Offline OP
Member
Joined: Oct 2000
Posts: 5,360
I have a new term " Hertz Vibration" that referes to the hum , noise, or other audible vibration heard from electrical gear.

note previuous thread; https://www.electrical-contractor.net/ubb/Forum2/HTML/000235.html

I don't know if the term is valid, or if so, the noise measurable ( I beleive ballasts have a sound rating) or how this side effect is produced or anything else....
cranium firmly imbeded in large intestine here...please feel free to call in the jaws of life if needed..

I have had the opportunity to be working in a panel yes, live and hear breakers buzzing under a load, some i have held my finger on and altered the noise level
were's that dutch boy when ya need im'

If this is indeed a bona-fide phenomenon, i am curious as to the details, if i have just been gulible i'll go buy more lottery tickets...

[Linked Image]

Tools for Electricians:
Re: Audible Hertz #127522
08/13/01 07:41 PM
08/13/01 07:41 PM
sparky66wv  Offline
Member
Joined: Nov 2000
Posts: 2,236
West Virginia
All kidding aside...

Are the CB's loose? (Like the old GE, they had problems) Even with a tight connection on the buss, older GE type breakers were loose enough to buzz under load... Got a bad rep from 'em, but have improved their product dramatically, in my opinion.

Is the vibration at 60 hertz?

The reason I ask, the Xformer for the music festval had a buzz at 120 hertz without any load (for those that don't know me, I'm a musician, trust me) which would be the first harmonic (wouldn't it?) I found that odd, and there was some hum on the sound system too, but at 60 hertz. (all sound was on one buss)

Most 60 cycle related vibration I've run into is usually at the 60 hertz fundamental frequency, the usual fluoros, dimmers, Xformers, etc.

I've heard breakers buzz under overcurrent situations right before they trip. Always when exceeding the rating of the OCPD, not under normal operation other than the GE's mentioned before, and they were giving 80%+ of their rated ampacity.

I think Bill has the right idea about it being similar to the whipping effect the filament in a bulb may experience.

Am I close?


-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI
Re: Audible Hertz #127523
08/14/01 08:18 AM
08/14/01 08:18 AM
Bill Addiss  Offline
Member
Joined: Oct 2000
Posts: 3,902
NY, USA
Sparky,

I passed the Question along to a Product Safety Engineering Newsgroup I belong to.

I'll post any relavant responses.

So far:
Quote

>>sounds like a bad rental car experience<< [Linked Image]
(I just got that one!)

>>It's likely a term used to describe the mechanical vibrations that you hear in a magnetic circuit breaker as the current it is carrying increases past its trip current. I've heard this noise, but not the term "Hertz vibration". However the name makes sense - the vibration would be at line frequency.<<

>>Must be something like "line buzz".
Happened at a place where we used a lot
of transfomers. If the transformer wasn't enamalled correctly, there'd be a loose winding that would buzz with the line frequncy.<<

>>The problem with overheard remarks is that you don't know if what is reported is a complete phrase or not. In this case, for example, there would be no mystery if the word 'sixty' occurred before the reported phrase.<<

Re: Audible Hertz #127524
08/14/01 07:59 PM
08/14/01 07:59 PM
S
sparky  Offline OP
Member
Joined: Oct 2000
Posts: 5,360
hmm;
The notion that the sound created could be realted to physical movement make me nervous..
That would mean something is loose right?

Re: Audible Hertz #127525
08/14/01 08:24 PM
08/14/01 08:24 PM
G
gpowellpec  Offline
Member
Joined: Dec 2000
Posts: 127
Irving, Tx USA
I did a Google search on "hertz vibration" and got sites where the term is used in reference to magnetic vibrations of the earth and vibrations of towers. Maybe the guy was getting his terminology crossed if he was talking about electrical.

Re: Audible Hertz #127526
08/14/01 08:37 PM
08/14/01 08:37 PM
A
Anonymous
Unregistered

>The notion that the sound created could be related to physical movement
Sound is a physical movement created by physical movement.

Re: Audible Hertz #127527
08/15/01 06:37 PM
08/15/01 06:37 PM
Bill Addiss  Offline
Member
Joined: Oct 2000
Posts: 3,902
NY, USA
Another Response on the subject:

Quote
I found quite a lot of references via Google, to 'Hertzian Vibration.' A lot of them made reference to contact closure types of equipment. By inference, it seems to be used in relation to low-frequency mechanical vibration.


Still sounds like a stupid bit of pseudo jargon to me. Like 'Hourly time' or 'Gallonic volume.' It's just wrong.


Sparky,

Can you think of a way to make sound without vibration?

Bill

Re: Audible Hertz #127528
08/15/01 09:12 PM
08/15/01 09:12 PM
S
sparky  Offline OP
Member
Joined: Oct 2000
Posts: 5,360
no, not really
[Linked Image]


Featured:

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
mxslick
mxslick
Atomic City, ID USA
Posts: 803
Joined: October 2004
Show All Member Profiles 
Top Posters(30 Days)
Admin 13
Trumpy 9
Popular Topics(Views)
249,439 Are you busy
187,355 Re: Forum
176,696 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.022s Queries: 14 (0.004s) Memory: 0.9931 MB (Peak: 1.1530 MB) Zlib enabled. Server Time: 2018-09-24 23:20:20 UTC