do you have link for unistrut large size cable strap?
DLO - Diesel Locomotive Cable
- Thread starter anbm
- Start date
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Structure engineer needs to involve if EC suspend cable with unistrut & cable clamp/strap from structure above?
- Location
- New Jersey
- Occupation
- Journeyman Electrician
I guess that depends on where you're hanging it. In a plant there might be someone who cares how it's suspended but on a construction site no.
- Location
- Illinois
- Occupation
- retired electrician
With very high current and assuming that the strut and strut strap are ferrous, I can see a potential for inductive heating at the support point assuming there is only a single AC conductor run through the porcelain. Probably not a real world issue unless the current on the conductor exceeds 400 amps.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
I'm pretty sure someone makes a strap/insulator that would fit the 3 cables in one strap. Besides the theoretical issue you've mentioned I've never seen a problem in the field even when the conductors are individually strapped.
- Location
- Illinois
- Occupation
- retired electrician
I have seen this arrangement on 5kv cables where the straps were noticeably warm, but not hot enough to damage. Not sure what the current on the 5kv cables was.
Birken Vogt
Senior Member
- Location
- Grass Valley, Ca
I saw it once in a strange situation.
Battery inverter conductors left a gutter to a battery box at individual KOs with bushings or something.
Well the inverters allowed a lot of ripple current onto those DC wires, a couple hundred amps DC and a couple hundred amps ripple as well as measured by Fluke amp clamp.
Those gutters about wanted to jump off the wall when the loads got heavy, or the sun got high (they were also charging). The buzzing and rattling was intense.
The customer just lived with it like that, it was a separate shed. Still like that afaik.