It’s Christmas and everyone is looking forward to the time off. All that’s left to do is to switch off all the equipment on the line, turn the lights off, and head home. How you do this, however, will have a major impact on what happens when you start up again in January.
If you don’t shut down your line and all the supporting systems above it properly and in sequence before the break for Christmas, the first shift back in January will face significant issues. In fact, you could lose 20 to 40 percent of your first shift in January because of start-up problems. These are easily avoidable with some forward thinking.
Generating Christmas Errors
Properly shutting down your production line, particularly automated systems, before you break for Christmas involves taking into consideration level two and level three systems as well as level one systems.
These higher-level systems are invisible when you have your hand on the machine isolator. These systems are usually hosted outside the manufacturing space and are involved with processing batch data, equipment access control, machine parameters, machine utilisation data, process data, etc. Even though they are outside the manufacturing space, it is essential you consider them in relation to their status of operation when they don’t have a connected machine controller for the holidays.
An example is the data connection between a batch control system in the MES layer and the equipment, the system that monitors the batch integrity of your line. By not taking this data connection into account, the system remains in an unknown state over the Christmas period. In other words, it won’t be able to confirm the status of the production equipment, so will still expect the same data. This can generate ever growing connection and error logs.
These are errors and connection issues that you will need to resolve before you can get production back up and running again. This takes time and needs to be done before you get the system back to a position where you are ready to download, line clear, and process the next batch number. That means lost productivity and, potentially, additional expense.
Controlling the Christmas Shutdown
The solution is to plan the Christmas shutdown looking at all layers of the organisation. This involves understanding how different pieces of equipment and systems interact. In other words, what happens to A and B when I switch off C?
Once you understand how everything interacts, you can produce a shutdown sequence to follow on the last day of operation before the break. Following this to the letter will turn off the equipment and higher level systems in a way that doesn’t generate errors or unnecessary notifications.
You should also produce a January start-up sequence to switch on all systems and equipment again in the right order, i.e. to ensure there are no problems starting a particular piece of equipment or software system before another one.
Preparation is Better than Resolving After the Fact
It is possible to resolve issues that occur because of incorrect shutdown or start-up sequencing. In fact, we help clients with these problems every year. That said, it’s not the best option as it’s cheaper and more productive to plan the shutdown and start-up sequence in advance.
When our team prepares a controlled Christmas shutdown and start-up plan, we do the following:
- Evaluate the system and identify all the interacting systems at the different levels.
- Develop an architectural model to determine the correct shutdown and start-up sequences
- Recommend the shutdown and start-up sequences to ensure the restart in January happens as quickly and smoothly as possible.
In addition, we often provide remote support through monitoring software where our engineers check all levels of automation, from machines to servers, during the shutdown and start-up processes. For some clients, we also provide engineers on-site.
Whatever way you choose to develop a Christmas shutdown and start-up plan, make sure you do it sooner rather than later. Integrated and automated systems provide benefits when they are operational but headaches when they are not stopped and started in the right sequence. A small amount of planning now avoids these problems.
To find out more about how SL Controls can help with your Christmas shutdown or start-up planning, please email us at firstname.lastname@example.org.