What the thread found

• Connecting auxiliary devices like wireless transmitters to the auxiliary D-tap on a cinema sled in 24V mode can cause power imbalance and errors because the auxiliary battery's negative terminal is connected in series to the camera battery's positive terminal in this configuration.
• When equipment draws power unevenly between the camera and auxiliary batteries in 24V mode, the camera may compensate by drawing excessive current from one battery, triggering error messages and display flashing on the camera and batteries.
• Video devices connected to the auxiliary power tap in 24V mode can create a short circuit between the negative terminal of the auxiliary battery and the positive terminal of the camera battery through their BNC shield connections, potentially damaging equipment.
• The camera battery power tap remains safe for powering auxiliary devices in both 12V and 24V modes, whereas the auxiliary power taps should not be used for external devices when operating in 24V mode.
• Reconfiguring the power setup to draw auxiliary receiver power from the monitor battery instead of the auxiliary battery prevented power imbalance problems on similar rigs.
• Operating the same camera and accessory setup in 12V mode using two batteries in parallel did not produce the power-related errors encountered in 24V mode.

Depends on

• The exact wiring configuration of the sled was not independently verified by all participants in the discussion.
• Most of the technical explanation is based on one participant's understanding rather than official manufacturer specifications.
• The manufacturer's position on whether the auxiliary D-tap should be used in 24V mode was unclear or disputed among participants.
• The discussion did not include confirmation from the rig manufacturer regarding the specific power distribution design.
• Only one concrete resolution was confirmed: powering the camera with a battery mounted directly on the camera instead of through the sled avoided the errors entirely.

Gear in this thread

BFD

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