Dear Colleagues,
It seems, on reflection, that over time I have had the dubious honour of travelling to ‘out of the way’ places. Two weeks ago, I participated in an Engineering Roadshow where we presented short lectures to engineering professionals in various out-of-city locations. A range of exhibitors promoted their wares alongside us. It is always particularly enjoyable meeting those of you who come along. The tricky challenge on these excursions seems always to be tangled up in the logistics - arriving at the designated hotel at 11.30 at night and allocated - by the disinterested hotel receptionist - a room to share (fortunately not a bed).
Despite this and inevitably, I always learn more from the highly interactive guys attending the presentations, than they do from me. I try hard to be a jack of all trades and remain at the technical forefront of all these different subjects, but it can be quite challenging. Still it is good fun and I gain enormously from the experience.
The following contains a summary of the wisdom I gained (or had reinforced) from the wonderful audience on this last Roadshow:
Troubleshooting Industrial Ethernet:
The real Ethernet networking problem is often completely different to that which is reported to you by the operators. It is essential, therefore, to ensure that you identify the exact issue and then test this to verify your solution.
If you are installing Ethernet in a grimy plant ensure it is real industrial strength. Do not tolerate RJ-45 connectors and wimpy commercial products in a sweaty, hot, vibrating industrial plant. (These may pass if you are installing your Ethernet kit in a nice clean, air conditioned environment)
The Nuts and Bolts of Smart Instrumentation Standards:
Do not worry excessively about the best Fieldbus standard. It is more important to ensure you use a standard which is supported by your top support vendor (whether it be: Foundation Fieldbus, Profibus, DeviceNet, etc). Another important issue is to have an easy connection into Ethernet through a proven gateway. And high quality cabling and installation practice is still imperative.
Troubleshooting Variable Speed Drives:
Watch out for harmonics and ensure good screening practice with your comms cables.
Ensure you de-rate for high temperatures (and altitude).
Many commented that the number of parameters (speed, current, acceleration times and other settings) available today can be daunting. But learning to work with a few key ones is deemed adequate.
Avoid overfluxing your motor.
Industrial Wireless Networks:
These are slowly creeping in everywhere and can easily be used in hazardous areas. The use of batteries with 7 years life, however, means that you won’t be able to poll them too often for data (once a minute perhaps).
Safety Instrumentation including Safety Integrity Levels (SILs):
SILs defines the degree of confidence placed in the ability of a system to provide functional safety - ranging from 1 (low) to 4 (very high). These are used everywhere today and are worthwhile understanding.
Surely, Jack London’s comment is true of engineering, especially when trying out new concepts:
You can't wait for inspiration. You have to go after it with a club.
Yours in engineering learning
Steve
