Hi,

I'm building a panel for one of our plastic molding machine that we refurbished.

As I don't have any certification but have played with automation stuff for the past 5 years, I would like to have some guidance on how and what should I take in consideration for the panel layout. It will be my first complete panel building.

I saw some panels that have their PLC at the bottom of the panel maybe for the heat dissipation I think... but most have their PLC in the top. What's the purpose of having the PLC at the bottom?

Maybe some example photos of panels would help me alot. I don't really know where to put inputs terminal block, outputs, control relays, transformers...etc.

After the completion of my panel, I will post picture of it to see what you think about it.

Thanx!

P.S. Sorry for my lack in english.

I like to mount my PLCs at eye level in the enclosure, or start near the top left and mount my enclosure so that the plc is close to eye level. I don't know of a standard for mounting them in any particular place, but there is probably one out there. One thing to watch out for is whether you mount it horizontal or vertical, follow the manufactures recommendations for spacing around it. I have seen where this affects the controllers ability to dissipate heat, and you may need to de-rate the back plane currents. Its a good idea to draw out your panel with all of the other components needed. This can sometimes dictate how you will need to mount stuff. If possible leave extra room. I can't count the number of times I have been given a panel to build and when I'm done "that guy" wants to add stuff he forgot about.



Check out the Gallery. Chakorules and others have some nice pictures of panels.

Yeah I have check all pictures of chakorules panels and they are neat!

Here is the begining of my panel layout in the pdf. Sorry if it's not very neat.

Now I want to put everything in this panel like power transformer, control transformer, line filter for my plc, power supply for my 24 vdc...etc everything! So this is why I want to know some guideline to avoid something bad like i.e. a transformer place too near of the PLC...

As I go further in the drawing of my panel, I see that I would need a bigger panel than expect.

Is there some kind of standard that I could check online? I know there is a book called NEC but don't want to buy it as I would probably build 10 panels in my whole life so... An online way would be cool!

I wouldn't place the outputs vertically. They might warm up eachother to the top.


Do you connect the output modules with multicore cables to the PLC ?
Be sure to have enough room in the cable ducting, especially the crossings get crowded with these cables.

I don't know why you wouldn't place outputs vertically, I do not think that a relay module would produce much heat...

As for the multicore I was thinking to leave them outside if it would cause problem.

My main worried is for the SSR that drive my band heaters. It will be the first time that I will played with SSR so I don't know how much heat they generate. I choose a 25A SSR but I will drive a load max 8A so I think the heat will not be a problem. I would probably put them on the bottom of the panel instead of placing them near the PLC.

Also, I want to know another thing. I will have the interface (HMI and pushbuttons) mount on a mobile stand. Does all the pushbutton must be hard-wired or I could use a distributed I/O? I know that an emergency button must be hard-wired to a master control relay but is it the same for every pushbutton? I meen directly connect to the PLC or they can go through a BUS?

Didn't know it was relay. At least I never put them vertically if only it was to easily read output numbers status.



Try to have the cable ducting big enough to fit them inside. You want a neat panel ?



SSR should come with a heatsink mounted big enough for it's max load. We always mount them next to eachother without any space in between. Horizontal of course.



If the buttons don't perform safety functions a bus shouldn't be a problem.

Ok Thanx alot PdL! Yeah my ducts will be 3 inch deep. Cables will be much straight with the duct that goes to my output module so they will not be kinked I think.

As for my SSR, Automation Direct says to put 3/4 inch between them but as I don't have the max load, maybe yes I could mount them next to each other.

What's do you all use to draw the electrical schematics?

I don't draw other than doodles but at the office they draw in Eplan.

NFPA has the 2005 NEC online at:
http://www.nfpa.org/freecodes/free_access_...t.asp?id=7005SB

The other important one for panel building is the 2007 NFPA 79:
http://www.nfpa.org/freecodes/free_access_...ent.asp?id=7907

I bought both of them in softcover for the company, but have to leave them in the toolroom (at the other end of the building) for the electricians so online is much quicker in the office. I can't print anything through the free portal, but it's very handy when I have to check something quick like wire gauge, etc. and don't feel like taking a walk.

HTH!
Susan

Thanx woman! Just to bad it have not more illustration but it will help me.

Personally I always try to keep everything horizontal due to the fact that I also always bring my cables in at the bottom and that it ends up being easyer to change things after the fact.

I have attached a rough drawing I did not do any measurements on it but this will keep everything neat and will probably allow you to add more into it later

Looks good! What type of PLC are you using? If it is a "brick" with a row of terminals along the top and along the bottom, consider mounting it so that there is wireduct above and below it. If you're using something that all the connections can be made at the bottom (SLC 500, etc.) than the way you have it is just fine.

good catch, I almost forgot that some PLC come that way - so used to using Omron - And device net...

A point of order here.

I notice you are in Canada. I am not, but I have done a lot of work there and I know for a fact that your control panel will need to have CSA approval on it or else it cannot be hooked up, at least no legally. ULc (UL for Canada) is an alternative, but more difficult to attain for you on your own. At the very least you should contact CSA and get a copy of their standards, they are very particular about construction, spacings, devices used etc. etc. They will come out and lable a panel for you on a one-off basis, but that is an expensive option and if you make a mistake, they will charge you again for re-inspection, and again and again until they are satisfied.

You might want to consider having your panel built by a CSA approved panel shop, that way they can put their label on it and there will be no problems with installation.

Actually I believe that if everything you use is CSA approved and you follow the Local Code you dont need CSA certification, Unless perhaps if you are making the panels for a machine IE a oven that will be sold in canada and then the whole machine needs to be CSA certifyed.

If you are making a one off panel as long as the panel and everything in it are CSA approved you dont need to get it recertifyed.

I may be wrong but that is the way my company works and they are by the books...