vac difference between legs of service

Reply

  #1  
Old 05-28-18, 10:42 AM
R
Member
Thread Starter
Join Date: Apr 2018
Location: usa
Posts: 69
Received 0 Votes on 0 Posts
vac difference between legs of service

How much difference in voltage between the two legs of a service, seen while under load, would you suspect a loose neutral? How much would you say is normal?

note I am saying under load, I would suspect both sides should be within a volt not under load.
 
Sponsored Links
  #2  
Old 05-28-18, 10:57 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 59,794
Received 1,193 Votes on 1,104 Posts
Under no load...... the voltages should be almost the same.
Depending on the load.... I would say no more than a 10 volt difference.

A 240v load will not unbalance the legs.
A heavy 120v load can cause an imbalance.
The further you are from the utility transformer the greater the drop.
 
  #3  
Old 05-28-18, 11:07 AM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 15,174
Received 92 Votes on 79 Posts
Depending on the loads the voltage swing can be quite a bit.
 
  #4  
Old 05-28-18, 11:36 AM
R
Member
Thread Starter
Join Date: Apr 2018
Location: usa
Posts: 69
Received 0 Votes on 0 Posts
And is the push/pull effect normal?

for example a hair dryer might bring one leg DOWN 2 vac and the other side RAISES 2 vac.
 
  #5  
Old 05-28-18, 11:40 AM
pcboss's Avatar
Forum Topic Moderator
Join Date: Jul 2002
Location: Maryland
Posts: 15,174
Received 92 Votes on 79 Posts
Correct. If one leg goes down by 30 volts the other leg goes up 30 volts.
 
  #6  
Old 05-28-18, 05:08 PM
A
Member
Join Date: Mar 2010
Location: USA
Posts: 4,163
Received 89 Votes on 82 Posts
I would say that if the other leg goes up by more than five volts then you should assume you have a broken neutral problem.

If the leg you are using a lot of power on goes down by several volts and the other leg also goes down by a volt or two then you do not have a neutral problem.
 
Reply
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: