×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Generator Actual Current Rating

Generator Actual Current Rating

Generator Actual Current Rating

(OP)
It seems basics but its confusing me:

The nameplate current rating of a genset is the current load on each phase or each phase x 3 or its In.
 

RE: Generator Actual Current Rating

It's the current out each of its individual cables - of which there are three.

It's what you can see with an ammeter clamped on a cable.

Keith Cress
kcress - http://www.flaminsystems.com

RE: Generator Actual Current Rating

It is the amount of per phase current in three phase.

 

RE: Generator Actual Current Rating

If current is 3200A then it means each phase will be having 3200A.

Simply speaking keep my below description as a thumb rule.

For Power-

3000kW of three phase load means 1000kW (Phase L1)+ 1000kW (Phase L2) and 1000kW (Phase L3)

For Current

3200A Three Phase means 5094A in L1, 5094A in L2 and 5094A in L3

Please check the attached file for quick reference.




If any confusion please intimate.

RE: Generator Actual Current Rating

For line

"3200A Three Phase means 5094A in L1, 5094A in L2 and 5094A in L3"

Please read

5094A Three Phase means 5094A in L1, 5094A in L2 and 5094A in L3

Sorry I typed wrong 3200A in that in place of 5094A.

 

RE: Generator Actual Current Rating

(OP)
Now, is In is the total current from all three phases? Do we add 3 currents on each phases?

RE: Generator Actual Current Rating

(OP)
I mean what 'In' would be out of those explained?

RE: Generator Actual Current Rating

In 5940A (3 Phase Current) In your case this is also equal to I Ll = I L2= I L3  

RE: Generator Actual Current Rating

(OP)
With different running current loads on 3 phases, do we take average of the 3 and would it be running In?

RE: Generator Actual Current Rating

No you cannot average them.

It load in one phase is 3000A and in other two 0A, then it doesn't mean that current in all phases equals to 1000A.

Never do that.

Simply get the currents based upon the loads that are connected to their phases.

  

RE: Generator Actual Current Rating

(OP)
My So 'In' is the total running load measured on one phase or altogether on all phases (their summation)? What actually 'In' is? Also we see on MCCBs

RE: Generator Actual Current Rating

"In" usually means the rated nominal current or the sensor size.

I would recommend you read instruction and operating manuals of the breakers and their trip units in question. Especially if the breaker has an adjustable electronic trip unit. You need to differentiate between sensor rating, plug rating and Long time pick up settings and where do they apply.

 

Rafiq Bulsara
http://www.srengineersct.com

RE: Generator Actual Current Rating

I've never seen In on a generator nameplate, but I haven't seen everything yet. I would assume In to mean Neutral current. It may be an indication of the maximum unbalance that the generator may accept without excessive rotor heating. I would be more comfortable seeing the whole nameplate. Seeing everything in context helps to understand unexpected ratings.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Generator Actual Current Rating

My last post was in response to the post immediately preceding it, referring to MCCB.

Rafiq Bulsara
http://www.srengineersct.com

RE: Generator Actual Current Rating

You may be correct Rafiq.  He may be looking at the generator breaker when he sees In.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Generator Actual Current Rating

I also feel that In is for Current to be taken for Breaker Rating or Bus bar Sizing.

Normally Current Ratings of Generators are in "AMPS"   

RE: Generator Actual Current Rating

(OP)
Infact my Energy Analyser is showing 'In' also. Actually I wanted to know what this 'In' is keeping in view IndianTechEngg1001's posts?  

RE: Generator Actual Current Rating

(OP)
Manual does not tell anything about 'In'. It seems its something all together all phases current. I would like to know what this 'In' is afterall?

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources