Power Injectors Vs Power Supplies for IP Phones
In many business settings, you still need landline phones, but that doesn’t mean you have to use traditional phone lines to fill that role. Many businesses use IP phones, as they are often more affordable and more capable.
When you do deploy IP phones, you might find that you want a phone in a place that isn’t easily powered. In such a case, you could consider using a PoE injector.
That brings us to an important question. How do PoE injectors compare to power supplies? Is one option better than the other? You’ll find the answers below.
Your IP phone needs electricity in order to work, and a power supply is the standard way to make that happen. Power supplies typically plug into a traditional wall outlet and transfer current to the phone. Most IP phones run on DC, so these power supplies usually also convert the AC from the wall to DC that the phone can utilize.
Considering most phones are designed with power supplies in mind, there are some clear pros and cons at play.
Starting with the pros, you can get a power supply that is designed specifically for your phone. That means you have a perfect voltage and current match. You don’t have to worry about how much juice is available from the outlet, and you don’t have to worry about any conversions or circuit math. Plug it in, and it works.
On top of that, power supplies are normally designed for regular, stable power. That stability can improve safety for the phone — often by providing an additional place for a circuit to break in the event of a power surge.
Most of all, a lot of IP phones come with power supplies included, in which case you can use them at no additional cost.
On the other hand, power supplies need direct access to your power infrastructure. In other words, you need an outlet close enough to use the power supply. If one isn’t available, you either need to add an outlet or use some type of extension cord, and in plenty of cases, neither of those options is viable.
As a result, power supplies are not as flexible for placement and overall infrastructure design.
You might think that power supplies are your only option, but IP phones can get power another way. Since they already use Ethernet to connect the “IP” aspect of the phone, it’s possible to draw power through those Ethernet lines. PoE injectors (or a PoE power supply) allow you to do this with phones that aren’t already designed with PoE in mind.
This opens up a lot of possibilities, and we can discuss that in terms of pros and cons.
The biggest advantage of PoE injectors is that they are flexible. Your IP phone already needs network access. The injectors allow you to power the phone anywhere that it can connect to your network (assuming it connects via Ethernet). That’s a powerful advantage and it means you don’t have to run extension cables or other awkward power extensions.
On top of that, PoE injectors are relatively cheap. They provide this flexibility without dramatically increasing your equipment costs.
There are a few drawbacks to consider. Most of all, PoE injectors offer limited scalability. Even if you have enough Ethernet ports for every phone, you also need enough power output from the PoE switch. If you don’t have enough power budget, the injectors can’t help.
Another catch is that PoE is not customized for powering your IP phone. You need to check your phone’s voltage requirements to ensure a safe and compatible operating environment. Many IP phones will work just fine with PoE injectors, but that won’t always be the case.
Which should you use? It’s really a matter of what you need and what costs the least. If you have plenty of outlet access, and your phones come with power supplies, then use them. It’s cheaper and simpler.
If you need a phone where electricity isn’t easily provided, PoE injectors solve that problem very efficiently.
Most importantly, you can mix and match how you power your phones. Some can use power supplies while others use injectors.
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