How to wire a motor from MCC

JohnnyTodd

Hi there,

I have an MCC in our plant that was installed about 5 years ago. Its a 690V one which uses Vacon VSDs and 1000VDc Active Front Ends.

I want to wire a motor to a spare VSD that was allocated also.

2 Questions:
1. Does it matter which way I wire the phases to the motor?
2. How do I isolate the drive so I dont shock myself while wiring?
3. Does anyone know the software I need to change the current setting in the drive?

2011

JohnnyTodd wrote: »

Hi there,

I have an MCC in our plant that was installed about 5 years ago. Its a 690V one which uses Vacon VSDs and 1000VDc Active Front Ends.

I want to wire a motor to a spare VSD that was allocated also.

2 Questions:
1. Does it matter which way I wire the phases to the motor?
2. How do I isolate the drive so I dont shock myself while wiring?
3. Does anyone know the software I need to change the current setting in the drive?

1. As in phase rotation? I am using ABB VSDs and for us it is easiest and best to swap phases if the direction is incorrect. I take it that you know if it should be in star or delta?

2. Upstream of the VSD. Normally there will be an MCCB, switch fuse or isolator. Normal LOTO procedure.
applies. Do not switch off the motor downstream of the VSD when it is running.

3. This would normally be done at the keypad for the VSDs I have worked with. Why do you want to change it? You may be able to download a manual.

JohnnyTodd

2011 wrote: »

1. As in phase rotation? I am using ABB VSDs and for us it is easiest and best to swap phases if the direction is incorrect. I take it that you know if it should be in star or delta?

2. Upstream of the VSD. Normally there will be an MCCB, switch fuse or isolator. Normal LOTO procedure.
applies. Do not switch off the motor downstream of the VSD when it is running.

3. This would normally be done at the keypad for the VSDs I have worked with. Why do you want to change it? You may be able to download a manual.

1. No just how to wire it properly. Does it matter which way I wire the phases. Will it change direction depending on which phases are wired?

2. There is a large ABB switchfuse. In the drive compartment. How can I be sure if its isolated?

3. I think there is parameters such as FLC and Maxspeed which may need to be changed.

Do you know anything about Active Front Ends? If I shut that down will I lose all drives? Dont want to stop the plant.

If I want to measure voltage coming from the drive do I set my multimeter on AC or DC?

2011

1. The oreder the phases are wired will dictate phase rotation and motor direction of ratation (DOR). Although VSDs can change direction of rotation this can can invert signals on some VSDs such as the ABB units. For example we found that if the DOR was reversed the motor speed (that we bring to our control system over Profibus) became a negative value. Although we could invert this in the code the speed remained negative on the keypad display, which could lead to confusion. Therefore we bump test and swap phases if required.

2011

2. You may find that this is downstream of the VSD, be carefull !

Assuming the switchfuse is upstream of the VSD the normal LOTO procedure would be to:
a) Ensure there is no load
b) Switch off the switch fuse
c) Remove the fuses
d) Apply a clasp with a padlock on it for each person involved/impacted if the motor were to restart
e) Using test equipment ensure that the supply is off
f) Attempt to start the motor to ensure the isolation is effective

JohnnyTodd

OK great.

I can see here there is 3 fuses inside of the switchfuse. I'll take them out and I should be OK. I'll wire the motor and report back

The next thing I need to figure out is how to integrate it into the control program.

The drive is on DeviceNet and needs to be mapped into the Scanner according to the Systems Integrater that wrote the existing PLC code.

Unforuntately due to funding we cannot use them so I'm on my own here. Time to get the manual out on Allen Bradley PLCs!

2011

3) A few questions:
a) Is the new motor larger or smaller than the previous?
b) Is the new motor rated to run at the new speed set point?


It would be normal to change FLC and max speed at the keypad on most VSDs

Most modern VSD have active front end. This will not impact on the work you are carrying out, it helps improve power factor and reduce harmonic distortion.

In most plants it would be normal to be able to isolate a single drive. However depending on the process the loss of 1 drive may cause the plant to trip. I am not familar with your set up.

A VSD rectifies AC. Using PWM can generate AC at any voltage or frequency within a set range. That way it can start motors with constant current, constant torque and achieve very percise speed control. If it were to send DC to a 3 pahse AC motor the motor would not rotate. Therfore you will measure AC.

For example it is possible for a VSD to take in 400VAC at 50Hz and output 400VAC at 60Hz

2011

JohnnyTodd wrote: »

OK great.

I can see here there is 3 fuses inside of the switchfuse. I'll take them out and I should be OK. I'll wire the motor and report back

Ensure they are upstream of the VSD. You may get alarms on your control system as it may now loose comms. Always ring the control room!

2011

I gotta go, very busy at the momet. Will check this thread later. Be careful!

brightspark

JohnnyTodd wrote: »

1. No just how to wire it properly. Does it matter which way I wire the phases. Will it change direction depending on which phases are wired?

2. There is a large ABB switchfuse. In the drive compartment. How can I be sure if its isolated?

If I want to measure voltage coming from the drive do I set my multimeter on AC or DC?

@ OP,

This thread and others like it scare me.

Are you employed at your plant as an electrician?

Judging from your post you are considering working on complex electrical circuitry without apparently sufficient knowledge and experience.

I have no problem with unskilled persons changing light bulbs etc. but the wiring of a motor to a VSD is hardly something that should be undertaken based on pointers obtained from an internet forum, no matter how knowledgeable the contributers are.

Please get in someone competent to help you install the motor safely.

2011

I was just reading over the thread and I have to agree with Brightspark.
Clearly some assistance is required (more than you can get from a forum on the internet).

I take advice from a very experienced ABB engineer when I am unsure or making design changes.
Other considerations include soft and hardwired interlocks and these requirements will vary depending on the application.

We also have a proper LOTO and safe work permit (SWP) systems in place.
I get the impression that the OP doesn't or is unfamiliar with the correct procedure.

In addition, there are regulations that only apply to VSDs that designers and installers need to be aware of.
For example the cable between the drive and the motor must be screened and can not contain any conductors other than phase conductors.
Whereas motors fed from a DOL may have 3 phases and a CPC within a single cable.

There are also a number of additional safety concerns when using VSDs.

JohnnyTodd

brightspark wrote: »

@ OP,

This thread and others like it scare me.

Are you employed at your plant as an electrician?

Judging from your post you are considering working on complex electrical circuitry without apparently sufficient knowledge and experience.

I have no problem with unskilled persons changing light bulbs etc. but the wiring of a motor to a VSD is hardly something that should be undertaken based on pointers obtained from an internet forum, no matter how knowledgeable the contributers are.

Please get in someone competent to help you install the motor safely.

No I'm not an electrician. I accept I didn't know how to wire the motor but it was my first time.

I have it wired now. Have to modify some plc code to test

JohnnyTodd

I can start the drive from the keypad also I think

brightspark

@ OP

Your employer is in breach of the General Application Regulations 2007 section 88

Persons to be competent to prevent danger.
88. An employer shall ensure that no person is engaged in any work activity to which this Part relates where technical knowledge and experience is necessary to prevent danger unless that person is competent or is under such degree of supervision as is appropriate, having regard to the nature of the work.

JohnnyTodd

Ok found the parameters for full load current and max speed. Modified according to motor plate. Ran the drive up this motor at 5hz. All seems to be in order now.

Next I need to connect it to the field bus and couple it somehow to pump. Do you know if I can do this without shutting down process?

JohnnyTodd

brightspark wrote: »

@ OP

Your employer is in breach of the General Application Regulations 2007 section 88

This is exactly the sort of attitude that has this country on its knees.

The job has to be done. There's no money to do it. Let's all sit back and say " oh I don't know how" or "I'm not an electrician"

It's hardly rocket science . I'm not spark but I can assure you Im a lot more qualified than an electrician will ever be.

It's help I needed, not smart replies. If you can't help please don't bother to respond

2011

JohnnyTodd wrote: »

Next I need to connect it to the field bus

Same as before. Advise automation people of your intention.

couple it somehow to pump. Do you know if I can do this without shutting down process?

Mechanical issue. Depends in the process.

JohnnyTodd

Thanks for all your help 2011. Think I'm there now

m.j.w

JohnnyTodd wrote: »

This is exactly the sort of attitude that has this country on its knees.

The job has to be done. There's no money to do it. Let's all sit back and say " oh I don't know how" or "I'm not an electrician"

It's hardly rocket science . I'm not spark but I can assure you Im a lot more qualified than an electrician will ever be.

It's help I needed, not smart replies. If you can't help please don't bother to respond

Dont think you deserve anymore advice with a comment like that

refco

gotta agree with brightspark here who takes the fall should something go seriously wrong even if its in a couple of months time do you think your employer or supervisor wont point the finger
and for someone that thinks there more qualified than an electrican im fairly sure phase one in fas deals with multimetre settings and phase rotation

brightspark

I don't want to get into an argument but...

JohnnyTodd wrote: »

This is exactly the sort of attitude that has this country on its knees.

I think you might find a lot it was caused by people NOT following regulations, if the bankers, regulators , builders, developers had been monitored better perhaps our economy wouldn't have overheated, leaving us with massive debts, lots of poorly constructed buildings, flood plains built on, etc.

JohnnyTodd wrote: »

The job has to be done. There's no money to do it. Let's all sit back and say " oh I don't know how" or "I'm not an electrician"

Your boss could hire someone who knows what he is doing instead of someone who had to ask on an internet forum.

JohnnyTodd wrote: »

It's hardly rocket science . I'm not spark but I can assure you Im a lot more qualified than an electrician will ever be.

You may be more qualified but you certainly have very limited knowledge and experience of the work involved which means you are not competent as defined by law.

JohnnyTodd wrote: »

It's help I needed, not smart replies. If you can't help please don't bother to respond

I gave you good advice, not a smart reply. I don't know what area you are qualified in, but it obviously isn't electrical based on the basic nature of some of your questions.

As someone who is 'a lot more qualified' than I am, I am surprised that you didn't read the manufacturers documentation and then just do the job, instead of asking how to do it here.

JohnnyTodd

brightspark wrote: »

I don't want to get into an argument but...



I think you might find a lot it was caused by people NOT following regulations, if the bankers, regulators , builders, developers had been monitored better perhaps our economy wouldn't have overheated, leaving us with massive debts, lots of poorly constructed buildings, flood plains built on, etc.



Your boss could hire someone who knows what he is doing instead of someone who had to ask on an internet forum.




You may be more qualified but you certainly have very limited knowledge and experience of the work involved which means you are not competent as defined by law.




I gave you good advice, not a smart reply. I don't know what area you are qualified in, but it obviously isn't electrical based on the basic nature of some of your questions.

As someone who is 'a lot more qualified' than I am, I am surprised that you didn't read the manufacturers documentation and then just do the job, instead of asking how to do it here.

Ok I accept some of what you say may very well be true in relation to regulations etc etc.

My boss cannot afford to hire someone to make small changes to plant operation due to the lack on money. We are a small company of 60-70 people and are on its knees.

Again I accept I didnt know how to wire the motor, nor could I operate a Multimeter. But I do know! You are correct that I am not skilled in Electrical Engineering.

I didn't mean to sound arrogrant but it was very easy task when you learn how to do it. Theres a first time for everything and I'd have no problem if I had to do it again.

I couldn't read the manufacturers documentation as I simply didnt know where to look. The motors documentation? The drives documentation? The MCC's documentation?

I needed a quick fix and I found the guys on this forum to be both skilled and helpful. I hadnt the time to spend days scouring the internet or looking through documentation to learn how to wire a motor!

Hopefully I didnt offend you. It wasnt my intention.