Inverter, Atex Motors, Star, Delta

Please go and talk to an electrican who has basic control system knowledge on how to work with frequency drives. You have way to much to learn. This is a simple project. Let someone else take it on.

I apologize for not reading in detail the motor descriptions but if ATEX compliance is required, depending on the zone specific requirements must be met and it's something for specialists as if something goes wrong there will be serious liability issues.

I won't provide detailed solutions because it would end in a longer discussion and especially ATEX-conform design is not always that simple. Many supposedly ATEX-conform installations are indeed not fully conform, very common errors are for example wrong cable glands, cable routing errors of intrinsically safe circuits, ia vs. ib confusion, inappropriate motor protection, etc. And to make things even more complicated even experts don't always agree on how to define zones.

You won't get any help here.

"ATEX" is a French acronym meaning "Atmosphere Explosible", and encompasses a series of standards pertaining to equipment and personnel within hazardous locations.

By having no knowledge of the requirements and certainly no idea of the life ending potential of the job to hand you are a walking time bomb.

Seek professional, qualified, certified local help who is aware of the dangers of, and requirements for, electrical installations in explosive environments.

Sadly, you probably won't be one of the casualties if you proceed using advice gathered from unknown strangers on an anonymous forum.

OK,
I get you technical charactertistics of fans,also maximamal airflow (m3/h) for every fan is:
MAX 1. 10650 m3/hMAX2. 12750 m3/h
I realised that with fvd I will use only one type of connection or star or delta.
If I want provide those two maximal airflows, which type of connection should I use? (What frequeny would it be?) If I want half (m3/h)/2 I change only frequency; nothing else?
Summary which type of connection and what frequency would it be for lower speed, what frequency would it be for higher speed?
Do you need any additional informations to provide me an answer?

The first thing would be to know the zones as well as the type of the involved flammable gas or gases (if it's gas). From there you can check if the planned equipment is suitable or not, see the rating plate, the indicated ATEX specifications follow very strict rules.

Even if you use an approved drive you still have to check that the way you operate the motor does not represent a risk. Even when using only ATEX components with the required approval for the intended use you must still follow strict design rules.

Also it's not only about the electrical part, the whole system must be explosion-proof as explosions can also have non-electrical origins (e.g. mechanically created sparks or overheated parts).

But as said, unless your're a seasoned ATEX specialist you'd better hire an external consultant.

Chances are, he may be in an environment where he is the consultant. We see a lot of that here.

Forum is here to ask stupid questions and answering on them correctly or incorrectly.
There is no reason for arguing...
Who know is it my school project maybe?
Does anyone from here can answer me on question? If there is no enough informations please ask me... Do not think on ex zone vents are ex but not in the ex zone.
I need simple answers... Frequency range for my needs, and connection star or delta.
And comments if you have positive please.
Kind regards

I am positive that you need to find someone to educate you that speaks your language and knows your level of knowledge.

We don't do homework here.

The motor nameplate should show what possible voltages may be connected in either star or delta. Your 2800 rpm motors are presumably 50 Hz. Full rated fan flow should be at that speed/frequency. Half flow will be at half speed/frequency. Most VFDs have ways to program preset speeds, which can be selected by one or more switches.

As others have noted, wiring methods, cable gland sealing, etc., must be taken into account. I too urge consulting with knowledgeable persons.

Things you wrote me doesnt help me I knew them by myself. I am enough intelingent to understand someone who can help me.

I am not intersted in clasification of zone 0 1 2 ... Exd Exi Exe Exn equipment... Imagine you have that kind of motore how would you run it? You dont know the answer

Tornado

Thank you on answer.

I have no problem with vfd.

Its simple parametring 2 working frequency.

I am wondering only do I connect motor in delta or in star? What you think is better?

With frequency 50hz in any connection or star or delta I will have 2800 rpm am I right?

So higher speed is 50 hz, lower i need to find out.

I can connect it as star, and with frequency of 50 hz it will have 2800rpm and maximal m3/h.

Now how to know minimum frequency motor is made for?

Kind regards

What does the motor nameplate say? Most VFDs are probably connected in delta, but I know of no absolute requirement for that. The motor speed depends on the frequency, not on the voltage, but you need to be sure that the supplied voltage matches the motor requirements.

<unsubscribes> Will listen for the explosion.

Tornado,

Vfd and motor are compatibile.

I am not person who specified equipment I need only connect them. In first it was looking simple vfd cable motor connect and than change frequency.

But now i have guestions.

Which data from motor are you interested in?

It has to be simple. It is not a magyc to connect motor.

You need star and delta parameters?

Kind regards

Your questions do not make any sense at all. You need to bail out and get knowledgeable persons involved.

At his point I'd suggest a nitrogen or CO2 inertization of his whole plant. :) :) :)

Goodbye

Joe9,

The problem here is, as I posted in the other forum where you posted this question, that the very nature of your question demonstrates an insufficient level of knowledge to take on this project. The very fact that the motor is in ANY way associated with an ATEX environment means there are many more complex details regarding the use of a VFD for it, yet you are unfamiliar with even the most rudimentary elements of the task at hand. So in helping you, we become participants in a potential disaster. Even though we are essentially anonymous, we are nonetheless Engineers and cannot in good conscience and professional ethics, facilitate this.

I have to ask but are your inverters installed in the safe area or the hazardous area?

Also, what do your variable speed drive manuals and application notes available off the manufacturer's website have to say about proper connection? Your question regarding this just seems odd as your connection depends on available voltage and what country you are in.

Contact the motor manufacturer if the available motor literature is of no help, especially if you want to overrun the motor(s) higher than the line frequency (50 or 60Hz).

Either

• seek training within the facility, or
• delegate the task to someone who has received the training, or
• both.

Thank you very much on your answers.

Iam not a person who will do this. I just wanted to know how it works.

One person explained me detailed this problem. To me everything is clear I just wanted to know theory.

Some of you helped me to know but some of you not.

Question maybe looked funny because of my bad english. I even wasnt trying to be smart. forum use for sily questions. also when you were thinking that i want do this i get much more answers.

Kind regards