Results 1 to 7 of 7

When should circuit breaker contacts be lubricated?

    #1
  1. Join Date
    Jan 2015
    Posts
    8
    Reputation

    Question in question on the practice test

    I am new in this industry but am questioning an answer i got wrong on the practice test.

    Generally, when should circuit breaker contacts be lubricated?
    Your Answer: Circuit breaker contacts should not be lubricated.
    Obviously you see my answer of "contacts should not be lubricated", could this question be about hinge points that you would oil/lubricate. I asked a Level III I work with and he has never heard of lubricating the actual contacts. Does anyone have any clarification. Thanks in advance
    Reply to Post • 

  2. #2
  3. SecondGen's Avatar
    SecondGen is offline
    I push buttons.
    NETA Level III
    Join Date
    Jan 2014
    Location
    United States
    Posts
    163
    Reputation
    Circuit breaker contacts usually should not be lubricated. The heat from the current flow through the contacts breaks the lubricant down and causes contact resistance to increase. With that said, some manufacturers might recommend it.

    Check out this thread for more info -> http://testguy.net/threads/10-Do-You...se-CB-Contacts


    Quote Originally Posted by zofofg View Post
    I asked a Level III I work with and he has never heard of lubricating the actual contacts.
    Reply to Post • 
    Last edited by SecondGen; July 16, 2015 at 07:22 PM.

  4. #3
  5. Join Date
    Jun 2015
    Posts
    5
    Reputation
    i got this question wrong also. what is the correct answer?
    Reply to Post • 

  6. #4
  7. Join Date
    Jan 2015
    Posts
    8
    Reputation
    Thank You secondGen
    Reply to Post • 

  8. #5
  9. Join Date
    Jan 2015
    Posts
    8
    Reputation
    Quote Originally Posted by hy3533 View Post
    i got this question wrong also. what is the correct answer?
    Answer is only in corrosive atmosphere
    Reply to Post • 

  10. #6
  11. SecondGen's Avatar
    SecondGen is offline
    I push buttons.
    NETA Level III
    Join Date
    Jan 2014
    Location
    United States
    Posts
    163
    Reputation
    There is a lot of confusion around this question so hopefully this can add some insight to my previous post. I found this little blurb noteworthy from Square D regarding lubrication, with the key point being that lubricants also prevent corrosion:

    The function of a lubricant is simple - reduce friction between moving metal surfaces. A lubricant coats surfaces and resists being displaced by pressure, keeping the metal parts separated. Lubricants also prevent corrosion, block contaminants and can serve as a coolant. A good lubricant flows easily under pressure and remains in contact with moving surfaces. It does not leak out from gravitational or centrifugal forces, nor does it stiffen in cold temperatures.
    I said before that circuit breaker contacts usually should not be lubricated because it can increase resistance, which is still true, but sometimes lightly lubricating the main contacts with an approved lubricant can guard against corrosion. It all depends on the environment, like a chemical plant for instance.


    Quote Originally Posted by zofofg View Post
    Answer is only in corrosive atmosphere

    Happy to help, zofofg.

    Quote Originally Posted by zofofg
    Thank You secondGen
    Reply to Post • 

  12. #7
  13. Join Date
    Jun 2015
    Posts
    12
    Reputation
    thanks this was helpful
    Reply to Post • 

Login or register to leave a reply!



Related Topics

  1. Identify this circuit breaker symbol
    By MAKI2016 in forum NETA Level 2 Exam
    Replies: 7
    Last Post: 4 Weeks Ago, 03:28 PM
  2. Contact resistance tester doesn't display any reading
    By lnides in forum Electrical Testing Talk
    Replies: 7
    Last Post: February 2, 2016, 10:53 PM
  3. Draw out circuit breaker positions, how many?
    By Mjeelemco in forum NETA Level 2 Exam
    Replies: 3
    Last Post: June 25, 2015, 06:55 PM
  4. Do You Ever Grease Circuit Breaker Contacts?
    By alexlounsbury in forum Electrical Testing Talk
    Replies: 7
    Last Post: May 21, 2014, 06:15 PM

Tags for this Thread

Search TestGuy
   Tag Cloud   Advanced Search
Follow us


Explore TestGuy


NETA Certification Training


Help and Support