sorry, I forgot to give more intended use info. I'll be operating at 220 v (which is like 2 110's) and 3KW spindle. I'm not real good on electronics but can rap my head around basics pretty well. Any info is greatly appreciated.

Tom, that contactor will be fine at 220v with a 3KW spindle. As Dave mentioned, if you tried were at 110, the amperage would be too high. At 220v, you have a comfortable safety margin.

Tom,

Those contactors are what I have used in my controller box. I bought most of the parts for my controller box from FactoryMation.

Except what I could get from Skycraft Surplus.

Now in one of the other post by Gerald he had a 'thermistor' for the spindle that was not needed if the spindle had such protection. How can I find these? I not even sure what to be looking for. I know that I may be wasting time if it is not needed but think it is smarter to know my options and what will be required when choosing my spindle (it will most likely be from China)

Nils, Did you have any Pics of your control box on the forum?

Tom,

http://www.mechmate.com/forums/showt...p?t=794&page=7 Post 270

That is when I had a router.

Thanks Nils, I just noticed that you live near Orlando, we have a place down in Cape Coral. I'll have to pay a visit next time we pass through. (if that's OK with you of coarse)

Tom,

I always enjoy talking to MM. I have had many visitors that have built MM machines.

I have sailed out of Cape Coral and Ft Myers. It is a very nice area and a great place to sail. You sail?

A contactor is not needed for a vfd. If your VFD is set up properly it will protect the drive. If you were looking at a main line contactor for your entire box, I would not go with an IEC. IEC is always on the light side. It should be as resistive load relay or a NEMA contactor. Being an electro-mechanical technician, I can tell you that high voltage coils are frowned upon because of the potential that is there when troubleshooting. If you are 230 3 phase then this would be your only option unless you have a neutral. I don't know if you have a wye or delta configuration if you are 3 phase. Since you are in the states, you should try to comply with NEC and NFPA79. NEC now dictates that you must comply with them for any wiring is not a system purchase from a manufacturer where before NFPA would allow exceptions if you were the builder.

Tom,

I bought my VFD from FactoryMation, Teco and I do not have it going throught my Controller Box. The extra contactor I have in my box was for my router. I ran 4 wires for the VFD-Spindle and it is 230.

My shop is in Orlando.

Nils, yes I do, I sold my 24' C&C Yacht two years ago. just didn't have the time. the nearest real water (in the mountains) is 80-90 minute drive away.

Pete, a NEMA contactor it'll be. I am using 220 single phase, so I should be able to go with the 3 pole, correct? I'm a little confused maybe by how the e-stop works with that & how it ties in. First, is the e-stop tied in at all? Is it the BOB that controls the estop then in turn cuts power at the contactor turning off the whole system. Can you help my understanding of this? I'm trying to understand how that contactor works.

The VFD should provide the protection to the spindle, so I shouldn't have to worry about it too much at this point. Thanks guys!

Hi Tom,

Check out starting on page 2 of my page "cutting some signs #95" we have along discussion on e stops, what should stop and what should not stop.

Al

Thanks Al, I have been following your build and I grasp it better after reviewing. Sometimes my head is a little thick, I do know that I'll get it better after I have most of the parts. I'm the type that has to have all things (or information) in place before it clicks.

Did you ever install that opto-isolator Brad had suggested?

Is this contactor Better? http://http://www.factorymation.com/...-11-AC230.html

Tom,

I purchased two of these for my controller box.

http://www.factorymation.com/Products/CU-22-F6.html

Hope that helps.

Thanks Nils, I think I just go with one of the two. Just came in from welding and grinding. Have completed the long side supports (minus the main rails) I'll post a pic as soon as I can find the camera.

Yes, you don't need two if you are going to have a spindle.

I've tried searching for instruction on posting pics and can't find it. Can someone point me to the posting? Thanks

All right lets try again, this is the first pictures of my progress, first is the lower frame sides and the other is a dry fit of the laser cut parts that Metalhead Mike provides, (thanks Mike)
Attachment 13855
Attachment 13856

The welding is not great but passable.

Sorry Tom for the late reply. Getting ready for Easter with the kids. Plus they shared their cold with me so I have a double whammy.

It is your choice on a Nema or IEC contactor. IEC is way undersized if you have ever tore one apart. The contact tips are tiny. The company I work for have started to use them to save money. They are less expensive that is for sure. On a lot of our motors we have had to upsize the IEC contactors by 2x their rated value to reduce the pitting on the contacts. IEC tend to stick if arcing occurs when the contacts close and open. Your largest arc is always on the opening and causes the most damage. A 20A IEC contact tips are only a little bigger than an 1/8 inch across. More likely to stick from pitting. IEC's are throw away contactors also. Nema can be rebuilt. We have machines built in the 60's that still have the same Nema contactors in them. If I was allowed, I would show the images from the thermographic surveys done with a FLIR of the different contactors. IEC run hotter and fail more frequently. Unfortunately I cannot as I am bound by confidentiality agreements.

So the bottom line is will they work? Yes. But they are application specific. They are great for the electronic overloads they can provide. It all depends on the electrical design and what they are controls and the arc potential.

I like to think in terms of preventive maintenance and spend more for less hassle later. I only used Definite Purpose Relays and Nema contactors for my heavy loads and main line contactor. I used Ice-Cubes for my signal switching. I was always told the the parts aren't cheap, they are less expensive and the person who bought them was cheap. :)

Tom,
Posting pictures works great from Flickr or Photobucket. You do not use up your allotment of space on the forum this way and you can post a larger picture as it is dictated from the BBCode. If you decide to go that way, I will help you with that. As far as which to go with, I would read the fine print on who retains ownership of the photos and make your decision from there.

Pete, sorry about the cold thing, leave it to the kids to bring it home.

Well, what is considered a 'heavy load'? And I'm assuming Ice-Cubes are the cheap guys

My biggest problem with any of them is that I don't know enough about what I'm looking at when searching (sensory overload I guess). I got a grip on the IEC contactors because that is what was offered (limited #'s) at places like Factorymation and Automationdirect, however I've done searches of the NEMA type and thousands of different contactors come up with many additional options ranging from $75 to $6000. That's great if I knew how to weed them out or had a more focused source.

Ok, I agree with quality parts. But if I where to use the IEC, I would assume that you would recommend doing a scheduled change out solely based on the potential issues. Is this an option? Because you say the others are repairable means they to have a useful life expectancy and requires maintenance as well.

Oh, I may have to do the photobucket or something, I'll try first before I start asking questions.

Tom,

Sorry but this will be long for you to understand.

For the most part, the Mechmate design requires minimal high voltage control requirement if any. Most of your input signals are going to the breakout board. We are looking the relay logic side of this only and not the breakout board.

An Ice cube relay can be used for a mild resistive load but it will arc. We use them for vibratory motion control. They last about 2 months with this application and the load is 7A. What it is controlling determines the life span. They will cycle a minimum of 1,000,000 times without failure in optimum conditions. They are best used for signal control in the mA range. That would mean switching the binary on or off logic for a branch circuit. An example would but pulling in a contactor. If you have a 24VDC proximity switch but you are pulling in a Size 2 Nema contactor the inrush current will slowly destroy your proximity switch so you would used the prox switch to control the ice cube relay. The line voltage then goes through the contacts of the ice cube and it controls the Nema contactor. This way your consumable is a $5 product and not a $100 dollar proximity switch. A control circuit in most industrial machinery uses 120VAC and 24VDC controls. You can use only 24VDC but the power supply is larger because of the lower voltage. On the other hand it is safer to work on and troubleshoot. Think of voltage like blood pressure. The lower it is the harder it has to work to bridge the gap. You will have more carbon build up on your contacts with a lower voltage. This raises the resistance and requires more amps to close the circuit. This is another theory vs reality problem that most new engineers learn after the first few years of designing and adjust their designs to compensate.

The nema and iec debate. This is a his or hers debate. If I use an IEC contactor, and I do in some of my panel designs, the working load I expect to see (lets say 18 amps), I will use an IEC contactor rated to handle 40A. This is based on my past history working with them. IEC relays are not to be confused with an IEC contactor. The relay is used for signal switching and therefore are not subjected to high make-break potential that you will see when controlling a motor.

One way to think about a relay is it makes a click sound and a contactor makes a CLUNK sound.

Good example of the differences between

Tom, you say you are using 220V. Single phase or Three Phase design? I used a Definite Purpose Contactor for my main line and dust collector. But I am using 220VAC Single Phase. You can get a 4 Pole 40A (50A resistive heating) for around $50. It is the gap between the extremes.

From your question
"Ok, I agree with quality parts. But if I were to use the IEC, I would assume that you would recommend doing a scheduled change out solely based on the potential issues. Is this an option? Because you say the others are repairable means they to have a useful life expectancy and requires maintenance as well."

If the IEC is oversized, it should last a long time at least 5+ years or longer if the duty cycle is very low. The only way to see if it is starting to fail though is with a thermographic device or it stops working. IEC do not come apart easily and are not meant to disassembled.

The most important thing is to size your components appropriately. You would not support something that weighed 100lbs with something that it's maximum capacity is 100lbs. The same is true with electricity. It needs wiggle room also.

Pete THANK YOU! I do understand this better than I thought. Its good to have good knowledgeable people around when you need them, Thanks Again!

No problem. Just trying to help.

I was in the shop cutting the 17g sheet metal for the control box and the 14g HF shear broke within the first 50", love that quality:rolleyes:. I'll pick up another blade tomorrow. A little trick when using one of these type of shears, spray a light film of wd-40 on the metal before you cut (I forgot)

Well Box is welded and primed. All I need are the hinges from grainger to weld on and viola! I'll post a pic tomorrow. The box is a little big but is probably good for air circulation, 24" x 24" x 10". Doing my taxes:(, can't spend too much time on this right now so I'll order some more stuff so it'll be here when I get this tax thing done.

Tom, my electrical enclosure is 24 x 36 x 10. I find my enclosure does not have any heat problems so you should be fine.

Thanks Pete, What do you think of putting a glass window in the box? I think I saw someone with one, thought it was cool:cool:

I think I might opt for plexiglass rather than real glass. :)

Mine is Plexiglass...Only way to go :)

http://www.mechmate.com/forums/showt...?t=2433&page=3

Details of the box start on post 88...

Looking cool is enough to justify any extra work ;)

Steve where did you find the window kit?

Window kits are for seeing the events happening inside. The best use of one would be for seeing the leds on your breakout board for troubleshooting.

Tom here is a link for the one I purchased...they have several different ones to pick from..
http://www.crazypc.com/products/casemods/windows.htm

They are under 20.00

I have used 1/4" polycarbonate before with edge trim over the hole in the metal. Use silicone to glue the poly to the steel and drill through the steel and poly then tap the poly and secure with machine screws. If you take your time it will look good but not as good as a standard window kit for a box enclosure.

This is what I use a work but they cost a bit more.