I have recently passed by the following transformer. It seems to be placed on rails and might be able to roll forward and backwars by about 0.5m each. There are no guards at the end of the rails though, at least not on the front facing end. What is the reason for the rails? It does look a bit like the red part on the top right might be disconnected when the transformer rolls away, but it was difficult to see from this perspective.

Brown Boveri transformer placed on rails, able to roll back and forth

  • \$\begingroup\$ maybe it rolls onto a truck platform during load/unload \$\endgroup\$
    – jsotola
    Commented Jul 9 at 19:44

1 Answer 1


BBC sells these "skid-mounted" transformers as something that can be quickly unloaded from a semi truck. So, the rails are mostly for mounting comfort. Hard for me to put a mass to that picture, but if I had to take a guess, it's 20 t to 30 t; so the process of removing the transformer from a truck (or putting it back on there at its end of life or for maintenance) deserves a bit of thought – and having a bit of freedom to be moved might make it easier than having fixed anchor points.

More interesting is that the rails are on heavy steel beams: I suspect the concrete structure this thing is mounted on is actually a simple "bath" to contain the transformer oil (or whatever thermally convective medium they use within) in the unlikely event the transformer tank fails. But I don't know!

  • \$\begingroup\$ Looking closely at the photo, it seems the lighter thing under the transformer is not concrete, but some sort of cover, something not load bearing, and the beams rest on the concrete rectangle. Which would explain the beams. \$\endgroup\$
    – jaskij
    Commented Jul 10 at 6:36
  • \$\begingroup\$ It looks to me, as though alignment in the fore-and-aft position needs to be relatively close to correct, so being able to easily adjust it during installation would be a bonus. \$\endgroup\$
    – MikeB
    Commented Jul 10 at 6:44
  • \$\begingroup\$ @jaskij Likely a sump for leaking transformer oil. It would be interesting if somebody could find a photo of a heavy lorry with matching rails permanently mounted. \$\endgroup\$ Commented Jul 10 at 6:44

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.