SDI and shielded cables

[JP Perry]

I'm reading the manual for my new-to-me Raptor, and I'm concerned about the warnings around the SDI ports. It says I need to use shielded 12G-SDI cables as well as shielded power cables for monitors and other attached SDI devices.

If I'm only monitoring in HD, I can't use the same BNC cables I've been using for years? I have tons of Belden and Canare cables ranging from 1ft to 50ft.

For AC power to monitors and other devices, I can't use standard "OHSA" power cables (NEMA 5-15 to C13)? I need to buy shielded versions? Is there a way to tell if my existing cables are shielded, such as a specific lettering on the jacket?

 

[Thomas B.]

Hi JP

As far as I know, SDI (coax) cables are shielded cables per se.
It is certainly a good idea to follow RED's recommendations, but I would have thought that you could use 3G-SDI cables as long as you set the correct frequency/resolution in the monitoring/SDI menu before plugging in these types of cables. If you want to be sure, you'd be better off checking with RED directly.
I would be very surprised if the 3-pin OSHA certified AC cables were not shielded for safety reasons. Perhaps you can find the specifications of the cable by searching the internet for its label. And what about the cable from the power supply to the accessory? I doubt the REDuser community can answer all your questions and assume that the majority use the power cables that come with the accessories.
I guess it is much more important for you as the operator to follow the instructions for the BNC connection.

Best regards.

 

[Howie Roll]

SDI coax is always shielded. The cable composition is literally a center conductor, dielectric, shield, and insulation.

Cable composition and certification isn't OSHA's department, that would be ANSI, NEMA, UL, CE, etc., AC is rarely shielded. When it is, it's usually foil to block RF emission. This foil has no effect on the issue at hand.

DC can be shielded, further this shield can be tied into a Lemo shell. This ensures that the first point of electrical contact will always be the ground, which is why it's suggested. A DC barrel or Ptap connection is no safer with a shielded cable as there is not a grounded metal shell. Frankly the shielding isn't strictly necessary so long as the conductive shell is tied to the ground. Conversely a Lemo outlet whose shell isn't tied to ground provides no protection from shielded cabling and connectors, looking at you Tilta.

Good Luck