PMP450x Release 15.1.2 is now available and can be downloaded at: https://support.cambiumnetworks.com/files/pmp450/
Hi, I seen this in the release notes:
* 450i CPY-14021 Added safety guard for 450i to prevent damage done to transmitter at extreme cold temperatures.
Can you elaborate? Symptoms? Is this damage on live radios or during power up after having been frozen? What's considered extreme cold anyway?
@Steven wrote:Hi, I seen this in the release notes:
* 450i CPY-14021 Added safety guard for 450i to prevent damage done to transmitter at extreme cold temperatures.
Can you elaborate? Symptoms? Is this damage on live radios or during power up after having been frozen? What's considered extreme cold anyway?
There's a heater in these radios to bring up the temperature of the RF components to a level that allows for predictable/stable operation. My guess is that when temps were too low, power draw was too high and/or the heating element was being stressed by being fed too much power to bring it up to operating temps within a given time period.
anyone having issues auto-update with cnut? It sends the files- then crashes goes red fails the progress and then reboots my aps.... I did update to 4.11.2 with the hotfix on cnut. Not sure if it's the firmware or cnut causing the issue.
Actually, the ePMP line has the heater circuit, not 450. We test our equipment across the entire operating range, which is -40 to +60 C, and found an issue in the factory while testing at extreme cold temperatures (-40 C to be exact).
The algorithms of the radio transmissions were adjusted to prevent any possible issues upon startup at these temperatures. This issue should not occur in the field, even without this fix, but in the case that something happens, it would present itself as a "damaged transmitter", resulting in poor performance (i.e. low Tx power or inability to maintain a link with the AP).
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Ugg looks like we lost about 10 APs across Alberta. They started going out at Christmas during the current cold spell.
We have 4x 900s per tower, we seem to have lost one per tower in six different remote communities...
The guys are upgrading firmware right now.
We lost one 900 450 AP but it looks like a cable connection. When we plug a 56 V powersupply and connect direct we do not get an enthernet connection. Happened at Christmas time as well?
Sorry blackberry, but are you saying the firmware update caused the radios to go off air?? Just trying to understand what's happening.
No I am not saying the firmware is causing issues. We are losing APs due to cold weather.
We upgraded all our AP firmware yesterday to latest, however we lost an additional four more 900 450i APs last night...
* 450i CPY-14021 Added safety guard for 450i to prevent damage done to transmitter at extreme cold temperatures.
We are still investigating the failures that occurred, but we do not believe they are in any way related to the cited issue (CPY-14021).