I am currently getting some custom cables made and having a serious communication issue with several cable manufacturers. I want several low voltage (5V DC) insulated conductors in a jacket that can protect from 600V external contact. And, I want the cable to be UL marked for flammability and voltage compliance.
If I am understanding my communications correctly, the different manufacturers have all indicated that the insulation for the individual wires must also resist 600V on their own for UL marking which makes the cable diameter very large. To me this does not make sense. I have been going through UL documents to try to see where this might be stated. Looking at AWM (appliance wiring) standards, I see detail about the jacket, but not about the individual conductors as in UL 20201 and UL 2057 for example. Given that AWM wires can contain twisted pair (assuming for communications), I would like to understand what I might be missing that would require cable internal wires to have such thick insulation.
I have looked at the "UL Marking and Application Guide Wire and Cable" in their tables and virtually every cable option requires UL marking with the UL symbol and voltage.
Is this possibly a case of the manufacturers trying to comply to a different standard than would apply? Is this a case of my application not being covered directly in the standards? Other options?
Any explanations and possible directions would be appreciated.