Powering an Arri SR3 camera with video tap on a Steadicam EFP rig without external battery tether

Gear

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Master SeriesIs a used Master Series rig worth buying as a first big rig?191

BFDHow do I power my BFD receiver from my camera or sled?186

VoltCan I retrofit a Volt onto my existing sled or gimbal?168

ArtemisHow do I power my camera and accessories from an Artemis sled?166

MDRWhere can I mount my Preston MDR on my rig?143

ModulusIs there a Modulus option for HD wireless video?141

G-70Will my G-70 fit my vest, gimbal or sled?126

FI+ZCan I control iris and zoom wirelessly, not just focus?60

HU3Where can I get my HU3 repaired, refurbished or repainted?60

CineLiveHow do I pack and case my CineLive rig for transport?54

G-70XHow does the G-70X compare to Pro Titan, Xarm and other arms?46

Trinity 2Is Trinity 2 SUP 3.0 firmware safe to install or buggy?46

Ultra VestWhich vest should I choose for my body size, comfort and operator type?39

2004Batteries/Power forum

22 years old. Gear and prices may have changed since.

DisputedParticipants disagreed and reached no conclusion. Read the findings as positions, not as an answer.

The original EFP Steadicam design uses 12 volts and cannot power a 24-volt Arri SR3 camera unless modified or adapted.
Two NP-1 batteries connected in series using connector caps can provide sufficient power for the camera and are light enough to attach to the sled with elastic bands or tape.
A Vicor voltage converter can step up power from onboard batteries to 24 volts for the camera and video assist system.
The Arri SR3 has an adapter that allows onboard batteries to connect directly via an XLR battery port, providing an alternative to external power.
Splitting power sources between onboard batteries for the camera and separate rig batteries for monitor and accessories can avoid overloading a single converter.
Depending on arm strength and lens weight, an EFP arm can support an SR3 camera with onboard battery without exceeding weight limits.
Cheap UHF wireless transmitter and receiver systems can work over short distances for video transmission, though broadcast regulations vary by location.

Weight constraints vary based on arm condition and lens choice; maximum viable rig weight reported as 25 pounds in one case.
Using the Vicor converter to power multiple devices simultaneously can cause power delivery problems.
Eyepiece heater cables must be disabled when using certain power configurations.
Regulations on amateur radio frequency use differ by location; legality of consumer wireless video systems is ambiguous in some regions.
The claim about cheap UHF transmitters remains untested in professional production contexts.