RelayPoint Technologies

RelayPoint Technologies · Norfolk County, Ontario

PoE Budget Calculator

Add up what your cameras, access points, door readers and phones actually draw, then see which UniFi switch has the power to run them. Built by the people who get called out when the cameras start rebooting at 2 a.m.

1 · What are you powering?

Example load

2 · How much room to leave

Headroom for the devices you will add later, and for cold nights when infrared and heaters all pull at once.

Recorder, desktops, printer, TV, anything that needs a port but brings its own power. One uplink port is added for you.

Only some UniFi switches accept a second power supply. Choose this if the cameras or door hardware cannot go down.

How the maths works

A switch has to put more power into the cable than the device takes out of it. The gap is heat lost in the copper, and the standards build it in: a switch reserves 15.4 W at the port to deliver 12.95 W of 802.3af, and 30 W to deliver 25.5 W of PoE+.

So this tool adds up the maximum draw Ubiquiti publishes for each device, adds about 18% for that cable loss, then adds your spare capacity on top. The result is the switch budget you should be shopping for, not the number on the back of the cameras.

Class-reserved figure: some switches hold back a full port class for every device that asks for one, whatever it actually uses. Where that matters we show it, and it is the safer number for a fixed-allocation setup.

What this cannot see

  • Cable length and quality. A 90 m run of thin unshielded cable loses more than the standards assume.
  • Voltage drop on outdoor runs in a Norfolk County January, which is when camera heaters draw hardest.
  • In-wall access points and door hubs that pass power through to something else. Add those downstream devices to the list too.
  • Whether the switch can breathe. A switch delivering 300 W in a sealed cupboard in July will throttle or fail early.

Power needed

0 devices
0W
switch PoE budget to look for
Devices 0 W Cable loss 0 W Spare 0 W
PoE ports
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Total ports
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Highest class

Switches that fit

UniFi, in stock in Canada

Get it quoted

Every job is quoted in writing before any work starts. Send us this build and we will confirm the switch, the cable runs and the labour for your site.

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