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7920 Battery Life and different wireless encryption settings

Does anyone have any input on the impact different wireless encryption

settings have on 7920 battery life?

I have a client that uses 128 bit WPA encryption on 7920s with the

cmterm_7920.4.0-03-02 firmware, and when the phones are up and

registered the battery lasts about 3 hrs when the phone is just

sitting there idle waiting for calls, etc.

I took another 7920 phone there, and it does the same thing. I had

left the site with a full charge on the 7920 and nearly 7 hours later

the phone still has one third of battery left but is not authenticated

to any wireless network and is sitting here trying to authenticate and

has been on since I left there so it doesn't appear to be a battery

issue but maybe something to do when it is up and running.


Re: 7920 Battery Life and different wireless encryption settings

encryption itself does not have an impact but the fact every time your device is registering or doing some activity its using some charge. The indirect energy usage due to the panel lighting up every time may be the main reason for battering usage. You may want to check for any faulty device 3hrs sounds too low. Check for cisco specs on 7920.

Please rate helpful posts.


Re: 7920 Battery Life and different wireless encryption settings

Well, all 3 7920s have the same problem. I took another 7920 with me there today that had a full charge and set it up for their WLAN and it from full to almost empty in 3 hrs, just sitting there on the desk registered to CME and idle. I made like 1 or 2 calls on it.

I charged the phone back up to full charge, and left the site and the phone lost its registration and has been sitting here trying to authenticate to the network for the past 10 hrs and still has one third of the battery left. I am far away from the site, so it isn't gonna find the network.

If it were a faulty device, then I would not think another working 7920 phone would exhibit the same symptoms when on their system.

Re: 7920 Battery Life and different wireless encryption settings

So anyone out there using 7920s with other encryption settings other then 128 bit WPA want to post your usual battery life from full to empty with the phone on and not plugged into a charger?

How about others with 7920s set up for 128 bit WPA (AKM checkbox)? How long does your battery last on the 7920 when it is powered on?

I don't see a power save mode on these, other then turning the backlight off.

I also opened a TAC case on this query, and they do not have any docs on this or numbers and are asking around.