As the father of a young and growing family the topic of long term maintenance costs have become front of mind. First, your hair is blown back when you see the cost of delivering your special bundle of joy. Then when you add the slow bleed of clothing, diapers, toys, visits to doctor, not to mention day care, extra-curricular activities, and saving for college, the costs pile up far beyond the initial investment. I wouldn’t trade my little wallet sucking parasites for the world but it is daunting to tabulate their bill.
The experience reminds me of a truth I was told early in my career that didn’t initially strike me as an epiphany. I was told “Devices aren’t the real cost of a machine assembly. It’s making them work that breaks the bank.” With a few more years of experience, and altered perception gained from family rearing, I believe I’ve finally absorbed this lesson branding it as the 30/10/60 Law. #30/10/60
What is the 30/10/60 Law?
The 30/10/60 Law states that on average the devices in an automated system or machine equate to only 30% of the total cost of the year one installation and operation. 10% gets eaten up by physical materials (i.e. wires, nuts bolts, mounts). That leaves 60% of the costs remaining in the installation labor, configuration programming and system tweaking. Hence the 30/10/60 Law. A universal truth.
How do you get to 60%?
This was the part I never understood at first. How can it be that high? Programming a PLC and configuring devices is challenging and takes significant labor but that doesn’t get close to 60% of the integration cost of a system. The strange happenings often overlooked have many names among the different engineering tribes. Some call the events Murphy’s law, Finagle’s Law or FUBAR. All describe the same phenomenon that drives the 60%.
What inevitably happens is that after a “completed” integration there are – little hiccups. A node randomly turns off and is nearly impossible to troubleshoot. A loss of power exposed the reboot cycle is not a properly synchronized event. Ground faults are discovered. Operators prove that two additional steps need to be automated. And the list goes on. These relatively small issues seem like annoyances at the time but lead to days of down time, wasted material, and missed quotas. Some of these costs and the associated opportunity cost are easy to overlook but I promise if you dig diligently enough you will prove the 30/10/60 Law correct.
Ignorance of the Law is No Excuse
There is no way to avoid the 30/10/60 Law. That said, there are still some practical lessons to be had. First, acknowledge the law. If you are holding the purse strings, recognize the devices are going to be a small piece of the whole pie. Your ROI is factored on more than just the BOM. Second, following the principles of the 30/10/60 Law, you know you are bound to experience pain after system deployment. Do yourself a favor and pick devices and partners that help limit this exposure.
Ancillary Principles to Alleviate Pain:
- Even the best devices will fail – When they do “Who you gonna call?” Will they answer?
- The best designs in the world are not the same as the best widgets in world – Do you have the flexibility to adapt your system/machine?
- The machine is going to cost two times its sticker price – Do you have the budget to deliver the solution?
Proud parents of both humans and machines should prepare for the inevitable costs of rearing and deployment. If you are looking for a protocol partner prepared to support you through your 30/10/60 deployment give us a call. Our EtherNet/IP, ASCII, Modbus, Profinet and BACnet solutions won’t break the 30/10/60 Law but our simple to use gateways and unmatched support sure will make complying with it a less painful experience.