PT-3 power leads are typically used to connect premade Siamese CCTV cable (plug and play security camera cables) to a DC power supply box. Also referred to as 12V DC Power Leads, PT-3s provide 6 inches of cable and a female connector for CCTV Camera power. The diameter of the connector is 2.1mm which is the standard size used for plug and play cables.
DC Power Lead Wire to Power Supply Box
The above diagram shows to use a PT-3 power lead to connect premade Siamese CCTV cables to a multi-channel power supply box. The 2.1mm female end of the PT-3 plugs into the power portion of the Siamese cable. Then the raw cable ends connect to the power supply box with screw terminals. The BNC video end of the cable connects to the back of the DVR (Not shown connected in the picture). You can see additional pictures that show how to connect CCTV cables to a power supply box here.
Using PT-3 Power Leads with RG59 Coax Cable
If you plan to use RG59 Siamese cable spools to install DC powered security cameras. Your DC cameras will most likely have a 2.1mm male power input plug. In order to attach the 18/2 power cable from the RG59 Siamese, installers can attach a PT-3 power lead to the 18 gauge power cable using butt connectors, B connectors, or the power wire connector of their choice.
Here is a complete HD CCTV camera installation diagram that uses an RG59 cable with an individual power transformer powering the camera from the DVR side of the cable run. You may click on the image for a higher resolution view.
- The RG59 Siamese cable is cut to the exact length required.
- On the camera side of the cable, a BNC connector is attached to the RG59 coax and a PT-3 power lead is attached to the 18/2 power cable.
- On the DVR side, a BNC connector allows the coax cable to connect to the video input of the DVR and PT-4 male 2.1mm power lead is attached to the 18/2 power wire with B connectors so that the power cable can attach to an individual power transformer - which has a 2.1mm female power connector.
CCTV Cable Installation Guides
We have the following installations guides available if you want to learn more about how to wire security camera systems (analog CCTV and HD).