Yesterday's Tractor Co. Parts for Farm Tractors - Compare our Prices!
Click Here or call 800-853-2651 
   Allis Chalmers Case Farmall IH Ford 9N,2N,8N Ford
   Ferguson John Deere Massey Ferguson Minn. Moline Oliver
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   Traditional YT Forum ViewClassic View   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Sparkie Question


 
Post new topic    
View previous topic :: View next topic  
Author Message
Eric in IL
Long Time User


Joined: 02 Dec 2005
Posts: 1060


Report to Moderator

PostPosted: Fri Jan 04, 2013 3:23 pm    Post subject: Sparkie Question Reply to specific post Reply with quote

I read an article in one of the farm magazines a while back that said if you had an electric motor wired to a circuit that was protected by a circuit breaker, you also needed the old screw-in melting type fuse/s in the line before the motor load.

I think they said the melting fuse was to protect the motor NOT the circuit.

Can anyone educate me on what they were thinking ?

Thanks Eric
 
Back to top
View user's profile
old
Tractor Guru


Joined: 12 Mar 2000
Posts: 57007
Location: Lake of the Ozarks area of MO

Report to Moderator

PostPosted: Fri Jan 04, 2013 5:42 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

Sounds wrong to me since a breaker or a fuse does the same thing. Only difference in the 2 is one burns out and you throw it away the other you just flip it back on but either way either one burns out or flips due to an over loaded circuit
 
Back to top
View user's profile
Dalex
Long Time User


Joined: 25 Apr 2009
Posts: 1084


Report to Moderator

PostPosted: Fri Jan 04, 2013 6:10 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

Could he have meant the "Heaters " in the magnetic starter ? I'll let someone more knowlegable explain them ....
 
Back to top
View user's profile
fixerupper
Tractor Guru


Joined: 12 Oct 2003
Posts: 9228
Location: Albert City Iowa

Report to Moderator

PostPosted: Fri Jan 04, 2013 6:11 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

I have heard that too. The characteristics are different in how the two react to an overload. Seems like an overloaded motor will melt a fuse before it will throw a breaker of the same amperage, but you have to use the right kind of fuse. I could be wrong. Jim
 
Back to top
View user's profile
John T
Tractor Guru


Joined: 14 Dec 1998
Posts: 14276


Report to Moderator

PostPosted: Fri Jan 04, 2013 7:11 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

Eric, my very first electrical engineering job fresh out of Purdue in the late sixties was with Century Electric Motor Company, so I will try my best to "educate" you as you asked.

1) The purpose of a fuze orrrrrrrrrrrrr circuit breaker is to protect the branch circuit feeder wires from short circuit protection and overload. If you have a branch circuit that requires wire rated for 30 amps, then you use a 30 amp fuze or circuit breaker to PROTECT THE BRANCH CIRCUIT FEED WIRES...

2) Next if you use a motor you also want it protected against over current and overheat so to protect the MOTOR you use some sort of a thermal overload device which may be a device called a "thermal" or a "heater" in a starter or perhaps an internal thermal overload (red button you depress to reset)

3) The fuze or circuit breaker is to protect the BRANCH CIRCUIT FEED WIRES,,,,,,,,,The purpose of a thermal overload or heaters or thermals is to protect the MOTOR.

Perhaps what you heard refers to the engineering design fact that the branch circuit may be protected by EITHER a fuze or circuit breaker while the motor itself is protected by a device such as a heater or thermal which can melt open a link (if excess current) to protect the MOTOR i.e. you need BOTH branch circuit protection PLUS motor protection which is often a heater or thermal similar to a fuze in that a link actually melts and opens the circuit to prevent motor damage from excess current.

YOU NEED BOTH,,,,,,,BREAKER OR FUZE TO PROTECT THE BRANCH CIRCUIT FEED WIRES PLUSSSSSSS A THERMAL OVERLOAD DEVICE (heater or thermal acts like a fuze) TO PROTECT THE MOTOR

Got it????????????????

John T BSEE, JD
 
Back to top
View user's profile
John T
Tractor Guru


Joined: 14 Dec 1998
Posts: 14276


Report to Moderator

PostPosted: Fri Jan 04, 2013 7:18 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

May "sound wrong" but actually its right, EITHER a fuze or circuit breaker is there to protect the branch circuit feeder wires,,,,,,While a thermal overload device (called heaters or thermals in a magnetic motor starter) is there to protect the MOTOR and its a device thats sorta like a fuze in that a link melts open to open the circuit so the motor cant over current or overheat.

There are TWO seperate protective functions involved with powering a motor, 1) A fuze or circuit breaker to protect the branch circuit feed wires, 2) A thermal overload device (thermals or heaters if in a magnetic starter act sorta like a fuze) to protect the motor and you need BOTH for best protection....

Hope this helps

John T
 
Back to top
View user's profile
Greg K
Tractor Expert


Joined: 04 Jan 2012
Posts: 1554


Report to Moderator

PostPosted: Fri Jan 04, 2013 7:28 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

Maybe depends which kind of fuse or breaker. There are instantaneus trip, nontime delay, time delay, and inverse time fuses. Now days most all breakers are dual rated as HACR and whatever the other rating is. However there are also breakers made specifically for HID lighting that are better designed to handle the inrush current of High Intensity Discharge lighting.

That being said, John T is corect in that now, the fuse or breaker protects the branch circuit and to a point the motor. The motor overloads thermally protect the motor.
 
Back to top
View user's profile
John T
Tractor Guru


Joined: 14 Dec 1998
Posts: 14276


Report to Moderator

PostPosted: Fri Jan 04, 2013 7:33 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

Duel element or time delay or K5 etc fuzes are to allow a motor to start since that may be like 5 times the run current!!!!!!! Yeppers, youre right on, the breaker or fuze in the panel is to protect the branch circuit feeders while the thermal overload device is to protect the motor, two seperate and distinct functions....Its NOT rocket scient but to lay persons it may be hard to understand???

John T
 
Back to top
View user's profile
Greg K
Tractor Expert


Joined: 04 Jan 2012
Posts: 1554


Report to Moderator

PostPosted: Fri Jan 04, 2013 7:52 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

It's sometimes difficult for me to understand! It is the same principle on that the breakers protect property and Ground Fault Circuit Interrupters (GFI's) protect people. If you don't understand the function it makes the rest of it confusing.
 
Back to top
View user's profile
JMOR
Tractor Guru


Joined: 13 Aug 2007
Posts: 15467


Report to Moderator

PostPosted: Fri Jan 04, 2013 8:24 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

Greg K wrote:
(quoted from post at 23:52:02 01/04/13) It's sometimes difficult for me to understand! It is the same principle on that the breakers protect property and Ground Fault Circuit Interrupters (GFI's) protect people. If you don't understand the function it makes the rest of it confusing.
Additionally, many motors already have thermal protectors built into the motor.
 
Back to top
View user's profile
wisbaker
Tractor Expert


Joined: 19 Oct 2007
Posts: 2209


Report to Moderator

PostPosted: Fri Jan 04, 2013 8:42 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

Not to be the grammar police but a FUZE goes in a bomb, its the first thing that goes to initiate an explosive train. A FUSE is a current limiting device placed in an electrical circuit.

Next week we'll discuss the difference between WELDER and a WELDOR.
 
Back to top
View user's profile
John T
Tractor Guru


Joined: 14 Dec 1998
Posts: 14276


Report to Moderator

PostPosted: Sat Jan 05, 2013 5:10 am    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

Good analogy to a point Id say,,,,,,the breaker protects the branch circuit feed wires from overheating and shorts and that can prevent a fire that could destroy LIFE ORRRRRRRRR PROPERTY

The GFCI is indeed aimed more towards saving a life!!!!!!

The thermals or heaters or internal thermal overload device is to protect the motor

Fun chat

John T
 
Back to top
View user's profile
buickanddeere
Tractor Guru


Joined: 31 May 2003
Posts: 26583
Location: in front of computer

Report to Moderator

PostPosted: Sat Jan 05, 2013 6:18 am    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

You are talking a about two of many kinds of motor and circuit protection.
There is short circuit protection which being either fuses and or breakers . That protects the supply circuit and wiring.
There is thermal protection which is the heaters inside the motor starter. Or on occasion a built in heater and reset button on the motor. This protects the motor.
 
Back to top
View user's profile
barnE
Long Time User


Joined: 07 Apr 2011
Posts: 875


Report to Moderator

PostPosted: Sat Jan 05, 2013 6:31 pm    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

Used to work with Edison engineers. Their oddest statement was that the "Safest house was the house with a fuse box." They insisted fuses were safer than circuit breakers because their calibration of breakers is questionable and they also can stick closed when they should open. Also more reasons I don't recall. Dave the absent minded electrician after 50 years.
 
Back to top
View user's profile
John T
Tractor Guru


Joined: 14 Dec 1998
Posts: 14276


Report to Moderator

PostPosted: Sun Jan 06, 2013 3:53 am    Post subject: Re: Sparkie Question Reply to specific post Reply with quote

As a retired electrical distribution design engineer I can verify some truth in your statement. The breaker is a mechanical device with springs and other mechanical devices while s fuse is a SIMPLE short piece of calibrated metal which simply melts and opens the circuit at given amperages.....While still not perfect, GOTTA BE MORE FOOLPROOF AND LESS PRONE TO MECHANICAL PROBLEMS.

John T
 
Back to top
View user's profile
Display posts from previous:   
Post new topic    Yesterday's Tractors Forum Index -> Tool Talk All times are GMT - 8 Hours
Page 1 of 1

 
Jump to:  
TRACTOR   PARTS TRACTOR   MANUALS
Same-Day Shipping! Most of our stocked parts ship the same day you order (M-F).  Expedited shipping available, just call!  Most prices for parts and manuals are below our competitors.  Compare our super low shipping rates!  We have the parts you need to repair your tractor.  We are a Company you can trust and have generous return policies!   Shop Online Today or call our friendly sales staff toll free (800) 853-2651.

YT Home  |  Forums Home

Copyright © 1997-2014 Yesterday's Tractor Co.

Powered by phpBB © 2001, 2005 phpBB Group

All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy

TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.

Yesterday's Tractors - Antique Tractor Headquarters