http://www.mijnwoordenboek.nl/EN/theme/EL/ES/EN/B/5botella terminal
ES: botella terminal, caja de extremidad
EN: terminal box
Definition EN: an enclosure which includes,mounts,and protects one or more terminals or terminal boards.It may include a cover and such accessories as mounting hardware,brackets,locks,and conduit fittings

Explanation:
one option:

botellas terminales de interconnexion=spouts


[PDF]
These Electricity Safety Rules and associated National Safety ...
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Formato de archivo: PDF/Adobe Acrobat - Vista rápida
High Voltage Metalclad Switchgear with Spouts. Safety and Environment Business Procedure ... and feeder spouts of High Voltage (HV) metalclad switchgear. ...
www.nationalgrid.com/.../UK_BP_SE_NSI3HVMetalcladSwitchgear...


Circuit Spouts / Bus Bar Spouts

Circuit spout / bus bar spout / RYB spout
Spouts basically designed in two heads viz. Circuit spouts and Bus Bar spouts We have wide variety of designs of both circuits and bus bar spouts which we are already supplying to our various valued customers.

Circuit Spouts / Bus Bar Spouts
Industrial Spouts
Industrial Spouts

All these various spouts are designed and made for varied demands and requirements of our customers. These are made keeping in mind the excellent surface finish and various technical parameters. Made of best quality material these bushings are made as per the exact industry specifications and offers best performance and durability.
See photos at:
Source: http://www.indiamart.com/epothane/epoxy-resin-cast-component...


You can see more at http://www.proz.com/kudoz/english_to_spanish/energy_power_ge... but I think at that time the chosen answer was not the right one.

Hope it helps
Regards :))

This is a little old, but interesting.