devicenet mcc

The company that I work for is building a new plant. They are going to use Intellicenter MCC's. The MCC will communicate with a controllogix controller via a 1756-dnb scanner. I would like to know what your thoughts, problems, benefits, good and bad, about this type of MCC are. Thanks in advance.

Don't know about the MCC, but why DeviceNet over ControlNet.

ControlNet is so much easier to commission.

I've only done one Intellicenter, with a SLC 5/05 and devicenet scanner card.

It was a royal PAIN.

SLC_Integrator said:

I've only done one Intellicenter, with a SLC 5/05 and devicenet scanner card.

It was a royal PAIN.

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Thats because you didn't watch the "How To" video.

http://www.youtube.com/watch?v=lBp5ag6SJH4&mode=related&search=

The mighty Turbo Encabulator!!

Its been called a few things over the years.
My personal favourite is the Self-Aligning Bonsomilator.

I always say DeviceNet is a lot like swimming; if you don't know the basics, you're in trouble. But the basics are easy to learn.

Use a decent 24VDC power supply. Ground the negative side. During commissioning, make sure you have a toggle breaker or other way to switch the DNet power off and on.

Install two 120 ohm terminating resistors at the ends of the trunkline. Put a label over whatever cover you put over them indicating where they are. Use an ohmmeter to verify there are two and only two connected (you will measure 60 ohms between blue and white with the power off).

There's a nice tutorial powerpoint slideshow that installs with RSNetworx for DeviceNet. You can learn the basics of upload/download/configuration with the software from that slideshow.

EDS files can intimidate the novice, but are not very difficult to manage. A CD full of them comes with your MCC, A-B posts them all on their website, and you can upload/create them with RSNetworx for most devices.

The new DeviceNet Tag Generator Utility takes a lot of the drudgery out of integrating RSNetworx and RSLogix 5000. Make sure you have RSNetworx v7 or v8 and it's included.

I am a big fan of the features that DeviceNet gets you. Digital speed reference and feedback from drives. A large handful of monitoring parameters from overload relays. A big reduction in wiring complexity.

Do some good labelling so you know which node you're looking at when you open the MCC bucket. Print out a list of the 1756-DNB status codes so you'll have them close at hand. Buy a very good terminal block screwdriver. Invest in some shrinkwrap tubing.

The length the DNet can run is much smaller that ControlNet.
If your PLC devicenet scanner is close to MCC you will be fine. If it is further away you may need a 1788-CN2DN Linking device.
At 125 kbit/sec the max. length of DNet is 500 meters.
At 500 kbit/sec the max. length of DNet is 100 meters.

Kim

Devicenet with contrologix PLC is sure a good combination to grab data from devices.

Intial Nodes and scanner commissioning takes a bit of time.
(Maaping the assembly words or to and fro data between master and devices,etc).
Once it is done then the Contrologix powerfull UDTs help a lot
to organise your data from the devices or nodes.

It is an intelligent choice to select MCC with devicenet network but some times it is painfull to resolves devicnet issues especially during the comissioning.
And most of the times devicenet netwrok failure is due to physical connections or power supply or noice problems.

My boss did not want to spend money on mcc's, so i designed our own mcc, it's been working so nice since then (may 2006).
My design was based on compact logix and 1769-sdn, if you go to ab.com you can download samples programs to diagnose devicenet network and devices themselves.
I use soft starters, ac drives and smart overload relays with devicenet interface installed, with the 1756-dnb you have and advantage over 1769-sdn because of bigger memory and of course more data.

Benny.

I have never used an Intellicenter but we do have many (hundreds) of motors controlled and monitored via E3Plus overloads and I would not dream of doing it any other way. Setting things up is very easy but you must ensure that the Devicenet installation is done correctly. My own preference would be for a custom built panel rather than a plug together solution as I find that plugs and sockets are one of the biggest sources of problems with Devicenet systems. Other things to watch for are missing terminating resistors and always ensure that the 0v line and the shield are solidly earthed.
Andybr

Mickey said:

Thats because you didn't watch the "How To" video.

Allen-Bradley Retro Entabulator

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LOL Made my day!

I always recommend against bus controlled equipment; be it MCC, VFD, instumentation, and so on.
Usually it looks cheaper with less wires and physical I/O modules.
But if something fails, the technician or engineer will have it diagnosed in a split second if signals are hardwired. A bus problem could take hours.
So how much does a production stop cost? Sometimes more than a hardwired MCC will.