DC power uses a supply with fixed polarity, with current flowing in one direction in normal operation. Batteries and regulated power supplies are common DC sources used with film-lighting equipment.
Battery voltage is a range
A battery’s nominal voltage is not its exact voltage throughout a discharge. Confirm that the complete working range is compatible with the fixture or required adapter. Some lights limit output on particular battery arrangements even when the mount fits.
Practical example
A fixture requiring a specified 48 V DC input cannot be assumed to run correctly from any battery plate connected to the same style of plug. The approved supply or converter must provide the correct voltage, polarity, wiring and current capability.
Power and runtime
For steady DC input, electrical power is voltage multiplied by current. Runtime calculations also need usable battery energy and conversion losses; amp-hours alone are difficult to compare across different voltages. DC input does not mean perfectly constant optical output, because the fixture’s dimming driver can still modulate the LEDs.
Equipment examples
The Aputure LS 600x Pro and Aputure Nova P600c have specified DC-power arrangements. Follow the model’s documented input and output restrictions.
Related terms
Voltage · Amperage · Watt · PWM (Pulse-Width Modulation) · AC Power
References
Fluke: electric current · Aputure: LS 600x Pro specifications · Aputure: Nova P600c