IEC Standard for Motor Starting Current!!!!!

I don't think that such IEC standard available. The standard will only guide the requirement of inrush current shall not damage the grid or influence other devices in network. 6 or 7 times higher than normal current just a reference that such inrush current shall not damage insulation of motor coil.

dbt

lightning.arrester,

Look here:

http://www.toolingu.com/definition-460250-34061-inrush-current.html

and here:

http://www.marathonelectric.com/motors/docs/manuals/SB537.pdf

and here:

http://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=00108470

You should be ashamed of yourself. What's wrong with you? I'm assuming you're older than 2 years old - how about showing some respect for others? Especially for some one who may be gifted enough to speak more than one language and may be trying very hard to make it in a place that is foreign to them.

I apologize for using this space to express my opinion but I couldn't help but respond. There is enough meanness in the world. We don't need it here. You're brand of humor is not welcome so please stop. And above else, it would be nice to see an apology to lightning.arrester.

DesparatelyHoldingOn,

The good DRFREON (or not so good actually) also owes an apology to another member. He did the same thing to him a Mr. sandeep lokhande. I was the guy who took him to task that time. I should have logged in as it was voted a GA - go figure.

The thread was titled Re: oil and gas industry .

We should ban this guy - he often acts this way.

It's a shame it might come to that. Even folks with bad manners can contribute in a positive may to society. Let's hope the good Lord helps DRFREON find his way. Peace!

..... but we shouldn't ban those who effectively cause accidents, deaths, billions of dollars in losses and insurance cost increases, because they don't communicate well- whatever the reason. Have you ever heard of unit crosschecking in calculations ?

THIS IS AN ENGINEERING site !

A large A/C unit manufacturer spec'd. an airflow wrong on one of my projects. Our engineers had no way of knowing this, as WE DEPEND on ACCURATE info. 20 of these were installed, only to find out the air flow was 30 % low. IT WAS A HOSPITAL, caused people to get more ill (remember Legionnaire's Disease- YOU NICE GUYS) and all the units to be torn out. I don't expect you to believe me when I say, its not where you're from or how you speak/ write, its inaccuracy I'm against. It can, is and will always be deadly or at least expensive. The specification engineer's name was PUNGI.

You can believe I'm joking, if you like. My family learned to read & write very well, prior to emigrating to the U.S.A. They did not have Internet, cell phones, IPods etc to help them. My belief is the majority of the world has gotten too damn lazy, & Liberals, who express comments very similar to yours, ENABLE THIS !!!

I understand what you are saying but you've missed the point. However I'd like not to use this space for further discussion on this matter because this is not the place for it. So I bid you farewell and peace. But before I go please try to be more compassionate toward others. Not all people fall into the category you are having issues with so please don't judge them - not knowing their 'story'. Thanks and no hard feelings on your judgement toward me!

The 6 times its full load current is considered the Locked Rotor Amperage of the motor if there is no other information given.

I don't know the exact standard but try this link (http://webstore.ansi.org/default.aspx). Good luck!

I think the standard you should look at is NEMA MG 1

Rule of thumb: the <...Starting Current of...> an <...Electric Motor...> is what it is, and is typically <...6 times...Full Load Current...>.

The need for a <...particular IEC Standard...> that says this is currently abstruse.

Yes. Not everything is defined by a “standard”. I have seen motors with a locked rotor current less than 600% and others with significantly more than that. It is what it is for any given design, but GENERALLY it can be assumed to be 600% if nothing else is known.

I don't think any standard stipulates starting current limits for motors. There are standards stipulating minimum Efficiency levels for motors.

In fact, higher the efficiency, higher is likely to be the motor starting current.

This suggests us that using high efficiency motor means dealing with higher starting current with associated issues on motor starting gear sizing and the starting voltage drops.

i

According to IEC 600034-12 there are 4 types of induction motors: N,NY,H,HY

NY and HY Motors similar to design N and H, but intended for star-delta starting.

Type N

Normal starting torque three-phase cage induction motors intended for direct-on-line starting having 2, 4, 6 or 8 poles and rated from 0.4 kW to 1 600 kW.

Type H

High starting torque three-phase cage induction motors with 4, 6 or 8 poles. intended for direct-online starting, and rated from 0,4 kW to 160 kW at a frequency of 60 Hz.

Thanks for the extract from IEC 60034-12. I stand corrected.

It's not as much <...shall not...> in an <...IEC Standard...> as "usually around" <...6 times of its Full Load Current...> according to experience.