How to Replace a Faulty CCTV Power Supply (SMPS)
If all your cameras suddenly go blank or show 'No Signal' at the same time, your central power supply (SMPS) is likely dead. Here is how to safely replace it.
Step-by-Step Instructions
Unplug from Mains
Safety First! Disconnect the main AC power cord of the SMPS from the wall socket. Use a line tester to ensure there is no electricity flowing into the box.
Warning
Never open or touch the internal components of an SMPS while it is plugged into the wall. AC voltage is lethal.
Take a Photo of the Wiring
Open the metal mesh cover of the old SMPS. You will see several wires connected to terminals labeled L, N, Earth, V+, and V-. Take a clear picture with your phone so you know exactly which wire goes where later.
Pro Tip
L (Line/Red) and N (Neutral/Black) are for 220V AC input. V+ (Red) and V- (Black) are the 12V DC output going to your cameras.
Disconnect Wires
Using a screwdriver, loosen the screws on the terminal block and pull out all the wires. Remove the old SMPS box from the wall.
Connect the New SMPS
Mount the new SMPS. Reconnect the wires exactly as they were in your photo. All Red camera wires go to V+ (or COM+). All Black camera wires go to V- (or COM-). Connect the main power cord to L and N.
Test the Cameras
Double-check that no wires are touching each other. Plug the main cord back into the wall socket and turn it on. A green LED should light up on the SMPS. Check your DVR screen; all cameras should be back online!
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Book a Technician NowTools Required
- Screwdriver Set
- New 4CH/8CH/16CH SMPSBuy in Store →
- Voltage Tester (Line Tester)