Maximum Voltage Drop
Industry Standard is maximum of 10% drop or a minimum voltage or 10.2 for a 12 volt CCTV or HD security camera
Amps (A) from Milli-amps (mA)
Some security camera specification sheets use mA instead of A – simple divide mA by 1000
800mA = 0.8A
Common Wire Gauges
RG59 Siamese (18/2) – 18AWG
Cat5e – 24AWG
Cat6 – 23AWG
Using Ohm’s Law Method
Voltage Drop = Load * Resistance
Resistance based on AWG resistance tables multiplied by complete circuit distance
CCTV Power Supply Voltage, Typically 12.5 to 13.2 volts for 12 volt systems and 24.5 to 25.5 volts for 24 volt systems.
Pure copper or CCA (Copper Clad Aluminum) NOTE: CCA adds significant resistance since the wire core is mostly aluminum.
Most professional CCTV cable is 18AWG. Select the exact gauge for proper voltage drop calculation.
Use max current draw (including IRs) in Amps from camera specifications
Measured cable distance from Power Supply to Camera.