We are often asked what would happen if the power is lost at your office.  Would the phones still function?

The answer is "Yes".  There are a couple of ways that this can work depending on the configuration of your office.

For all customers, if you were to lose power (or internet for that matter) at your office, the system would continue to function.  Your calls would still be able to go to aut attendants, vociemails.  You could also configure to transfer calls to your cellphone.

For customers with a UPS (Uninteruptable Power Supply) and  a POE (Power Over Ethernet) switch, this can easily be configured to ensure that the phones will continue to operate.  The Modem, router and POE switch should all be on the UPS.

UPSforVOIP

 

Selecting the Right UPS

There are two factors you should look for when selecting the UPS.  The power that it can deliver for your devices, and how long it will be able to keep them running in the event of a power failure

The power required for Modem/router/POE switch is quite low.  As a rule of thumb,

  • Most modems and small business routers will need less than 10w, so allow 20w  for the two
  • A POE switch for a small office would use up to 10w + 5w per phone, so for an office with 5 phones would be 35w

In this example, the total power would be 55w for all the devices, 65-70w adding a margin for error and some expansion.  This is the minimum power that the unit should supply.   Most UPs units for small offices operate for just a few minutes at their rated maximum power.

The question then is how long is would be able to supply the power that you consume for to run the phones.   This information takes a bit of research.  For a typical small business unit from APC that can provide 250-450w, you would get 30-60 minutes of runtime based on the specs.   Study the specification of the unit carefully before buying.  The graph below shows the runtime of a CyberPower OR700LCDRM1U . Rated at 400W, this shows that it would run for just a few minutes at the maximum rated power, but at 50w, would run for around an hour.

 UPSruntime graph