Wiring Motor Start Contactor Problem???

[Jraef]

Give it a few and you have the difference between a mW and a MW..............

Wait, there's a difference??? hmy:

 

[Besoeker]

Wait, there's a difference??? hmy:

So I've been led to believe.............

 

[GeorgeB]

Wait, there's a difference??? hmy:

Just 60dB.

 

[pjholguin]

Nice Job, a well laid out Control Panel... Makes for easy troubleshooting.

Yes, HVAC here is also made to a price and not necessarily to the neatest standard.
We mainly serve the industrial sector and this is typical stuff - poor pics but just done for the record but it gives an idea of the different approach.

View attachment 10075

 

[hurk27]

All I can say about the contactors is these are not a good design for a motor control system, from your post 3 it sounds like you temped them from a regular service panel so you should have enough power to pull in the contactors, unless you are getting a voltage drop which as was mentioned check with a DVM at the coils when you fire them up, it could very well be the timer is dropping the voltage if it is overloaded, I notice that you have 6 contactors one in front of each drive, are all the other contactors for control circuits? you could have saved some money as well as power consumption by using smaller control relays for the rest of the controls.

Some points to ponder, we tried those Siemens Sinamics v20 drives but we had to much problems with them and went to ABB or AB Flex drives, one thing they do not like is being disconnected from the load while the drive is still running so if you have disconnects at each motor make sure you have a micro switch to shut down the drive before the switch opens, also use reactors on the load side if the runs to the motors are long which with a conveyor system it most likely will be, also with these drives you have to configure them when wiring for a WYE or Delta motor so make sure you use the correct method for the motors you will be using, these are a very very basic drive.

If your not familiar with drives I would consult with someone who is or you are going to get into trouble real fast.

If the conveyors are inline where one feeds another what method are you going to use to sync the speeds of each, there are several methods, but which one depends upon how much money they want to spend, old school was lead and lag continuous turn variable resistors but you will need a interface for these drives, encoders are another method but more costly.


Designing control systems can be rewarding but there is allot to know.

Here is a small panel I installed for a lift station that has two AB Flex 70 drives, with a small PLC control, note that with PLC control how much less relays you need and you can do so much more, also this was at a location that didn't have 3-phase so the drives are also used to convert to 3-phase for the motors.

 

[ptonsparky]

It is always easier to suggest what should/could have been done.

VFDs have aux contacts that are programmable. This conveyor setup could have been done with No additional contactors, other than your E Stop. A CLICK PLC would have been less expensive than the contactors, with better control options, unless your intent was to totally isolate the drives both line and load side even while under normal control. The only reason I can see for using them at all.

 

[StarCat]

Nice Panels

Nice Panels

Yes, HVAC here is also made to a price and not necessarily to the neatest standard.
We mainly serve the industrial sector and this is typical stuff - poor pics but just done for the record but it gives an idea of the different approach.

View attachment 10075

Some nice looking control panels there.

SC

 

[Besoeker]

Nice Job, a well laid out Control Panel... Makes for easy troubleshooting.

Thanks to both yourself and StarCat.
It's a couple of small VSDs for a petrochem application and fairly typical of what we do.
Quite often the specifications require it - things like wire numbers, minimum conductor size, crimp terminals, labels etc. But it's what we would do anyway.

 

[Jraef]

Thanks to both yourself and StarCat.
It's a couple of small VSDs for a petrochem application and fairly typical of what we do.
Quite often the specifications require it - things like wire numbers, minimum conductor size, crimp terminals, labels etc. But it's what we would do anyway.

Yes, but if they SPECIFY it, you get to charge them extra for it! :angel:

 

[Besoeker]

Yes, but if they SPECIFY it, you get to charge them extra for it! :angel:

I wish!

A contract comes out to tender. We tender a fixed price. If we win the contract the only time we can charge extra is if the customer changes something and then a price adjustment is made.
Actually, contracts often have penalty clauses where money can be taken off for late delivery, incomplete or late submission of documentation, failure to meet declared performance on things like efficiency or harmonics.

Anyway, we do what we do because it's neat, professional, AND cost effective. Open slot trunking makes wiring easy and any modifications are easily implemented. The DIN rail makes it quick and easy to mount components.

A little slightly off topic little story. We do some control panels for different divisions of the mighty empire.
One day the lighting sales director cam into my office with a picture of a small panel that had been knocked up, I think by the development lab.
"Could your guys build kit like this?"
"No." I said.
He looked me as if I'd lost the plot.
"Um, why not?"
"They couldn't do such a krap (sorry mods) job".
"Oh."

Anyway, we've since done that and a few custom projects for them.
We've recently completed and shipped a project that has thirty odd panels for an overseas installation.
Unfortunately, the engineers on site (not mine) and the customer have come up with numerous changes so my guys have had to go there and implement these changes, some of which have subsequently been reversed. Because of the construction using DIN rail and trunking, it isn't too difficult to implement the changes. But a shame it's so far away.