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Guides for CCTV & electrical technicians
Practical write-ups on the mistakes that commonly happen in CCTV and electrical installs, and how to avoid them.
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NVR Storage Calculation: 12 Mistakes That Leave You Short on Space
The formula is simple — 12 real-world factors are why the calculated number is often wrong.
IP Camera Bandwidth: Why the Switch (and PoE Budget) Fail First
Switch uplink overload and PoE power budget — the check most junior installers skip.
Analog vs. IP CCTV in 2026: Which Should You Actually Install
A balanced breakdown of when each system makes sense — not just "newer is always better."
How to Choose the Right Battery Size for a Security Panel
Exact Ah calculation, series vs. parallel wiring, and why lithium usually wins now.
Choosing the Right CCTV Lens: Coverage vs. Identification Distance
Why a wider lens usually means less detail — and how to actually match focal length to the job.
PoE Budget Calculator: How Many Cameras Can Your Switch Run?
Port count isn't the same as power budget — the math behind cameras rebooting after dark.
CCTV Voltage Drop Calculator: Why Cameras Fail After Dark
Long or thin cable runs sag under night-time IR current. Find the right wire gauge before it costs you a callback.
How to Choose the Right Wire Size (AWG) for Any Circuit
Load current, the 125% rule, temperature ratings, derating and voltage drop, step by step with worked examples.
Conduit Fill Explained: How Many Wires Fit in a Conduit
The 53%, 31% and 40% limits, wire and conduit areas, and worked examples for sizing EMT.
First Login and Reset: What Happens the First Time You Power Up a Camera
Activation, the first password and the factory logins that Hikvision and Reolink publish, with links to the official Dahua and Axis pages.
Ports and Protocols for CCTV and IP Networks
RTSP, HTTP, HTTPS, NTP, SNMP and the other standard ports on a camera network, what each does and whether it is encrypted.