Tagged in: Education and Training
In my previous post, I have told you that me and my colleague of our maintenance department have been designing and creating this training and test rig for the various instrument installed plantwide. It was running smoothly, and we were able to configure our wifi module connected to our Allen-Bradley PLC with attached motor managers and HMI. Though still quite small in terms of equipment variety compared to those professional and commercially available in the market. It still manage to do its purpose.
Slowly expanding it in terms of material availability and time, my colleague and I do rotating turns in wiring and configuration since we still are attending numerous breakdown calls of the plant. If I am on the field or at the office doing our job reports, he will be the one doing the stuff needed for the completion of our self-proposed project. Everything went smooth since we are able to add a little 'feature' day by day when the one of our DeviceNet Module bugged down due to short circuit.
Our 24VDC linear power supply used to power our Allen-Bradley Flex I/O DeviceNet Adapter module got its fuse toasted. Good thing it was only the fuse that gave way during that failure.
It happened after I tried replacing the DeviceNet Adapter module just for the sake of practicing installation and configuration. Everything went fine until the moment I turned on the circuit breaker of the said power supply. Everything just went black with a spark.
And the culprit was traced to the unstandardized wiring color configuration. See the picture below for actual setup of the wire installation of the said module:
VDC Common, though coming from the same source is composed of two colors of wire: red and blue. 24+VDC (at the back portion and source is same) is also composed of two colors of wire: red and blue.Crazy huh.
When we did this, all we were thinking were functionality of the project. With time constraints, we did just to make it function. It was really a ticking time-bomb and even tripped it by ourselves, how much more to those guys whom we did the project for.
Now, we need to overhaul the power source wiring of the rig just to make everything fail-safe.
Lesson learned. Apply what you know.