CCTV · Software · ServiceCCTV help centre · free
CCTV problem? Let’s work it out together.
Plain answers to the problems we fix every week — for owners, managers and technicians. Search, ask the CCTV doctor, or work out your storage.
The CCTV doctor
Answer two or three questions. Get the likely cause and what to do.
Answers
Common CCTV problems, explained simply.
Each answer has what to try first, when to call a technician, and how monitoring would have caught it.
Storage calculator
How many days will my disks record?
A quick estimate for planning. Real numbers depend on the scene — a busy road at night needs far more than a quiet corridor.
Motion-only saving varies a lot; we assume roughly 45% of continuous.
Estimated footage kept
—
- Storage per day
- —
- Needed for 30 days
- —
- Bitrate per camera (approx.)
- —
Estimate only, at 25 fps with typical bitrates. Night scenes, rain and busy areas use more. We size real systems from your actual cameras.
CCTV words, decoded
The jargon, in one line each.
- NVR
- Network Video Recorder — records IP cameras over the network.
- DVR
- Digital Video Recorder — records analog / HD-analog cameras over coaxial cable.
- PoE
- Power over Ethernet — one network cable carries both picture and power to the camera.
- PoE budget
- The total power a switch can give all its cameras. Go over it and cameras reboot.
- IR / night vision
- Infrared lights that let the camera see in the dark, in black and white.
- H.265 / H.265+
- Video compression that needs much less disk space than older H.264.
- Retention
- How many days of footage the recorder keeps before overwriting the oldest.
- Packet loss
- Bits of the video stream that never arrive — a sign of a weak cable or link.
- CRC errors
- Damaged data counted by the switch — almost always a cable or connector problem.
- ONVIF
- A common standard that lets cameras and recorders of different brands work together.
- S.M.A.R.T.
- A hard disk’s own health report — temperature, hours and bad sectors.
- AMC
- Annual Maintenance Contract — planned service visits and repairs for a yearly fee.
Still stuck? Ask a real engineer.
Send a photo of the screen or the recorder label. We’ll tell you what we think — free, no obligation.