Error Analysis: Ground a Shield?
Engineers and makers can absorb a lot from books, courses, and tutorials. But many times, the best way to learn is by trial and error. Edward Mulder — a Houston, TX-based hardware engineer — shares a lesson he learned about grounding a shield.
Engineers and makers can absorb a lot from books, courses, and tutorials. But many times, the best way to learn is by trial and error. Edward Mulder — a Houston, TX-based hardware engineer and long-time Elektor reader — knows this well. By destroying some electronics a few decades ago, he learned a valuable lesson about grounding a shield. Most of you can likely relate.
Sparks From a Shield
“Twenty years ago, I made the mistake of not connecting the shielding of a fiber-optic cable, and subsequentially destroying the electronics. What was that all about? It turned out that the fiber-optic cable was running underground for 15 km in parallel with an overhead cable of 33 kV. Even though the fiber-optic was separated at least 8m from the high-voltage cable, running that long a distance induced high enough of a voltage in the metal shield of the fiber-optic. This caused sparks from the shield to the electronics. I destroyed two receivers before I got wise and asked the vendor for help. He had specifically placed a clause in the contract, stating that the shield had to be grounded. You learn either by going to school or paying for equipment you destroy. It was the latter in this case.” – Edward Mulder
Protect Your Electronics
Looking for tips on protecting your electronics? Consider these resources:
We want to hear about your electronics-relate errors and learnings. Fill out our "Error Analysis" form and share your experience. Pro engineers, makers, and students are welcome to contribute!
Sparks From a Shield
“Twenty years ago, I made the mistake of not connecting the shielding of a fiber-optic cable, and subsequentially destroying the electronics. What was that all about? It turned out that the fiber-optic cable was running underground for 15 km in parallel with an overhead cable of 33 kV. Even though the fiber-optic was separated at least 8m from the high-voltage cable, running that long a distance induced high enough of a voltage in the metal shield of the fiber-optic. This caused sparks from the shield to the electronics. I destroyed two receivers before I got wise and asked the vendor for help. He had specifically placed a clause in the contract, stating that the shield had to be grounded. You learn either by going to school or paying for equipment you destroy. It was the latter in this case.” – Edward Mulder
Protect Your Electronics
Looking for tips on protecting your electronics? Consider these resources:
- T. Wescott, “How to Protect Electronic Components and Machines from Electrostatic Discharge”, ElektorMagazine.com, January 2019.
- P. Kruger, "Active ESD Protection," Elektor Jan/Feb 2014.
- K. Notte, "When the Sparks Fly," Elektor Industry 2/2019.
- M. Sonst, "EMI Debugging with an Oscilloscope," Elektor Industry 1/2020.
We want to hear about your electronics-relate errors and learnings. Fill out our "Error Analysis" form and share your experience. Pro engineers, makers, and students are welcome to contribute!
