buy or fabricate

mannyb

Senior Member
I need around 8 to 10 combo motor starters with with basic stop start and coouple with HOAs. If I get these off the shelf they are kinda expensive so I was considering maybe building my own. I was wondering if anyone has found this cost effective. We have the time just wondering if its worth the money.
 

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
Depends on a lot of details left out, but generally it only makes sense if you don’t value your time very highly.
Not to mention, I doubt you are going to have your home-brews listed by UL, and that may be a requirement either for your jurisdiction or your customer.
 

powerpete69

Senior Member
Location
Northeast, Ohio
Occupation
XXX
How about a nice mini- MCC?
Home brewed combo motor starters prob not a good idea for a professional.
Best to get the pre-made combo starters. Shop around and get multiple bids from the big players like Schneider, Eaton, ABB, etc...and whoever I am forgetting.

When you do finally get the best bid. Counter offer that offer. They may just give in knowing that "you may be going to the competition".

That being said, as a hobby for home, might be cool to build a motor starter that works.
 

ptonsparky

Senior Member
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
Electrical Contractor
I have used an online supplier that has a wide selection of materials. Lots of information available. That many motors would be fun to connect to a small PLC, add an HMI. I’m salivating.

an MCC is a good option. Make sure you add spares now. The price to add later is enormous.
 

tom baker

First Chief Moderator
Staff member
You can contact a system integrator, they can build for you, or get bids as mentioned, With 8-10 you should get a good price.
You can not build for the same price as purchase, as the integrators (panel shops) get a better discount than you do, plus they know what works. I have done a lot of motor control, modified many controllers, and on cost tracking, its better to have them built, as you get good drawings and documentation. Plus they will be UL listed, and in my state thats required.
 

Jraef

Moderator
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
... The price to add later is enormous.
While true, there is a trick to this;

MCCs are sold by everyone as a "loss leader", meaning they don't make a lot of profit on them as a project item, but they intend to make it up later when you buy individual add-on buckets. But you can "game" the system if you need more than 2 buckets by simply buying it as a "new project MCC" and get the bare minimum structure/bus etc., focusing on the bucket specs instead. Then those buckets come to you in a "handy steel shipping container" that you sell for scrap after you pull the buckets out. It will cost you less.
 

tom baker

First Chief Moderator
Staff member
If all the motor controllers are to be located in the same area, then an MCC is the way to go. RE: Jraefs comments, if we needed a replacement or new bucket, we would buy an MCC section with the bucket included, use the bucket and scrap the section.
 

ptonsparky

Senior Member
Location
NE (9.06 miles @5.9 Degrees from Winged Horses)
Occupation
Electrical Contractor
While true, there is a trick to this;

MCCs are sold by everyone as a "loss leader", meaning they don't make a lot of profit on them as a project item, but they intend to make it up later when you buy individual add-on buckets. But you can "game" the system if you need more than 2 buckets by simply buying it as a "new project MCC" and get the bare minimum structure/bus etc., focusing on the bucket specs instead. Then those buckets come to you in a "handy steel shipping container" that you sell for scrap after you pull the buckets out. It will cost you less.
Yes, I’ve done it that way. A customer changed motor hps on us so we had a new project quoted with the proper buckets. The old buckets are stored in the new section of MCC that sets off in the corner out of the way.
 

hbiss

EC, Westchester, New York NEC: 2014
Location
Hawthorne, New York NEC: 2014
Occupation
EC
Not to mention, I doubt you are going to have your home-brews listed by UL, and that may be a requirement either for your jurisdiction or your customer.
Every so often we get questions about controls for Ansul systems and restaurant hoods. I know sometimes it's easy to come up with a design for it, but I always suggest a pre-made panel. Not only is it ready to go and listed, but I cringe when I think about what some of these people who ask the questions will build. It's kinda "if you have to ask you shouldn't be doing it".

-Hal
 

mannyb

Senior Member
Thanks for all the comments. They wont spend the money on MCC. They currenty disconnects as the on and off for mixers. none of the equipment has any kinda starters. They use mixers for simple blending. I wanted to put a simple stop/start with combo motor starter nothing expensive.
 

Jraef

Moderator
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
Thanks for all the comments. They wont spend the money on MCC. They currenty disconnects as the on and off for mixers. none of the equipment has any kinda starters. They use mixers for simple blending. I wanted to put a simple stop/start with combo motor starter nothing expensive.
So how are they protecting the motors in terms of Over Load? Do all of the mixer motors have internal thermal protectors embedded in them?

The point is that sometimes when companies do things on their own, they don't do what is required because they don't fully understand. It's (in my opinion) incumbent on electrical professionals to make them understand the basic requirements and code provisions. Leaving things as they had them may not be a valid option once you have seen that it is wrong.
 

Besoeker3

Senior Member
Location
UK
Usually we built from component level but they were normally a small part of a much larger system that we built an enclosure. The nature of what we did - custom built large variable speed drives.

But, if you just need a system with a few basic starters buying in from a supplier who does that as a business might be a less expensive option.
 

mannyb

Senior Member
I agree with all the post. The shop is a new shop and looking for ways to cut down on cost. I tell them the exact same thing you guys are telling me. The time we would spend building or constructing is a lot less expensive. They have lots of motors for various functions and non of these motors are compliant. The motors have under and over sized fuses, no starters, no grounding, no enclosures, you name it its there. i was just ttying to find an ecomonical way to help customer. I even gave them the name of my supplier so they could by equipment themselves. I told then I cant do work without following codes and regulations. I appreciate the input
 

JeffKiper

Electrical geek
Occupation
Controls guy
Not trying to troll you for work. Just tossing out an idea go look at theautimationstore.com. they might have prices that will make it worth your time to buy them.
 

kwired

Electron manager
Location
NE Nebraska
I can see some not thinking proper overload protection is necessarily worth it with general purpose motor of maybe 5 hp or less, especially if you have an application that would seldom have mechanical overloading. Those motors are low enough cost and some places may have spare motors in stock for replacements where necessary and might see them as expendible. Even having overload protection but not setting it properly may not really save you much. Sure you may have less shut down on small overloads, but allowing to run at a little higher loading still is going to lessen winding life over time. Having proper protection and paying attention to what is going on when it does trip maybe would lead one to realize they have undersized equipment to begin with (for what they are demanding it to do anyway). This not only lessens motor life but possibly other driven components over time as well.
 

Jraef

Moderator
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
It should be noted however, motor thermal overload and short circuit protection is a non-negotiable requirement per the NEC. There are several ways to achieve it, but ignoring it is a Code violation. Then should something overload, catch fire and cause damage, an insurance company may not cover the damage costs if they discover a non-code installation.
 
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