Motor control centers are the unsung heroes of almost every manufacturing facility, yet often don’t enough attention. What is the cost of their failure?
By Jonathan Smith, field business leader, Drives, Rockwell Automation
What keeps plant managers awake at night?
Chances are, it’s whether their production processes are going to be reliable and consistent so that both output and quality will be maintained.
And where do managers look for reassurance that everything is working as it should be?
It’s probably in the heart of the operation: the automation control room. Or, maybe they have already begun The Connected Enterprise journey and have access to performance and operational trends through smart device data acquisition and can view this information remotely.
Having access to this data and information is, of course, reassuring, but is there still critical equipment that managers can’t see? Unseen equipment that, if it failed, would create a major headache (or worse) in production loss and might prove difficult to repair quickly?
Most plants rely heavily on electric motors. Whether fixed or variable speed, they provide the motive force that transports, cuts, mixes, pumps, cools, doses, aerates, packages and drives all manner of processes that products need to undergo before they’re ready for dispatch and sale.
While the demand control of these motors comes from the programmable automation controller (PAC), the actual switching of the electrical load is usually through a motor control center (MCC).
Dealing with Reliability
Frequently, MCCs aren’t located in the same area as the automation control equipment, but rather in plant rooms or switch rooms. And they quietly (or not so quietly) get on with their work. Their reliability — which is usually impressive — is their worst enemy.
Why? Well, when something just gets on and works, it’s easy for it to simply be taken for granted. An expectation that just grows with each passing month or year.
But of course, nothing lasts forever and when the inevitable failure does come, it’s at best an inconvenience and at worst catastrophic.
It doesn’t have to be like this. MCCs can be intelligent. They can be integrated through EtherNet/IPTM into your Connected Enterprise, and they can provide important information on the health of not just themselves, but also the motors and machines they feed.
They can provide trends for energy use — often in much more granular detail than conventional energy monitoring. They even can provide advance information before a trip condition actually occurs. Intelligent MCCs can be a principle supporter for predictive maintenance on a plant-wide scale.
Additionally, modern MCCs are designed to be easily maintained.
For example, a compartmentalized “Form 4” construction with withdrawable buckets or assemblies means that should a problem occur, a replacement can be fitted in seconds. The “intelligent” aspect of the MCC can take care of the configuration and overload settings automatically.
Deserving of Consideration
MCCs are fundamental in any installation that uses electric motors. That means that nearly every factory in the world relies on them. They provide the electrical power and protection necessary for safe and reliable operation of the motors in your plant. When did you last think about them?
And if MCCs were smarter, would you sleep a little easier?
The Journal From Rockwell Automation and Our PartnerNetwork™ is published by Putman Media, Inc.