sundance-communications.com/forum Forums Other TDM Phone Systems ESI Telephones & Systems 48 Key IP FP2 Phone Watt Requirement

Does anyone know what the Watt Requirement is for the 48 Key IP FP2 Phones? I am having problems with intermittent garbled voice on the ip phones. Looking into Bandwidth and Power Requirements per phone to make sure its not network/power overload.

15.5 watts per phone conforming to IEEE 802.3af Power over Ethernet standard. (Minimum 44 VDC at 350ma.) Most POE equipment will provide 48 VDC and, therefore, the 350ma spec is actually 322ma.

Rcaman

Thanks, Do you know how much bandwidth the phones take up? we have 22 of these ip phones on one network wanted to make sure were not going to run into issues. We have 10 mb up/down.

Each IP phone will need, at a bare minimum, 22 Kb bandwidth. However, that's just one issue to consider. The network latency is just as an important factor as the bandwidth. You must multiply the number of phones by the bandwidth (22 x 22 Kb) and that's the bare minimum bandwidth needed to have the phones connect, reliably. In your case, you need 484 Kb just for the phones.

In my experience, I have insisted that the remote phones be allocated 64 Kb for each phone with a latency of less than 2 ms. For your situation, that would mean you would be utilizing 1,408 KB just for the phones.

Now, the real problem comes when you add in the bandwidth needed for the rest of the data being carried on that same circuit.

I would suggest you contact a certified ESI dealer or get a good network mechanic to run a "network sniffer" type software on the circuit and determine if you can actually support all the phones AND the data load on that circuit. The problems I run into with remote phones and the "static" or choppy voice is usually due to huge bursts of data from applications running on computers on the network.

Another point to consider: Purchase the best switch you can afford. Also, watch the POE specifications of the remote switch. ESI sells POE adapters that can be attached to each phone to avoid the costly POE switch. Make sure the switch is, at least, a 1 Gb switch.

Lastly, have you considered purchasing another KSU for the remote site and using ESI-Link between the main system and the remote? Doing that would greatly reduce the bandwidth utilization and support.

Rcaman

ESI is does not handle jitter and latency well. Your speeds are fine. But with that said Rcaman is correct about bursts and what there network is using. In most cases this is not a problem. Exceptions would be huge graphic files sent back and forth. Data between offices is small.

ESI Link, is not going to solve your problem.

I would not do a 1GB switch, it will make the problem worse if you have a bandwidth problem.

First off, a 1GB switch will only do good or bad if your computers have a 1GB Nic card. If your computers have a 1GB NIC card, they will get the lion share of the speed, your phones will then have less speed and have more problems if it is a bandwidth problem.
If the phones are sharing the same network as the computers than a 1gIG SWITCH WILL DO NOTHING!

Here is what I need to know to help you:

Are you working of the computer network with the IP phones?
Or do you have a stand alone network for the phones?
If the later, do a Vlan

Walter

I have a few comments regarding Walterv's post. He is entitled to his opinion.

The suggestion, if possible, to use a VLan is a good one.

The comments about a 1 Gb switch are misleading. If you have a bigger funnel, things move more quickly. Sure, if you have a data hog computer and a 1 Gb NIC card, that computer will occupy a lot of real estate. However, managed switches allow you to proportion and allocate bandwidth. That is why I suggested getting the best switch you can afford. A cheap, non managed switch will do exactly what Walterv wrote.

I think your best solution would be to contact a certified ESI dealer in your area and have that technician do some simple LAN tests to determine if your LAN can support the ESI remote phones.

Rcaman