Frost problem?

[zrob_12]

I currently have 4 PS5 and 4 NS5 in operation. We had a heavy frost this morning and the temp is currently 16F. All of my PS5s are still up and running, but every NS5 is not connected to the AP. Is frost causing this or what?

[zrob_12]

All but one of the NS5 are now online. When observing the units, I don't see any frost of them. Is the cold causing this? How can I prevent this from happening again?

[WHT]

I don't know of any referenced information on this, but ice is transparent to RF. Stick an ice cube in your microwave...it doesn't melt.

I'm going to say your problem is more likely caused by a severe temperature inversion. Check the clients that aren't connecting. I'll bet the closer clients are all right, its just the far out ones that are dropping.

[MaximumISP]

I would say its something else your seeing happen such as WHT suggests or
possibly as simple as snow build up then eventually melting
if you do think its cold related Id first try bumping up the power supply
to an 18v unit (should throw off a lil more heat internally)

All my NS have seen -7 C (19F)
so far without problems but
since they are rated for -20C
I would expect that they will operate until at least that temp
without too much difficulty

I have a crap load of them up north here so I will defintely
be keeping a watchfull eye out for when and if they do drop off
this winter and will be ready to start rolling out the NS maximum cold editions ..:wink:

[WHT]

I'm thinking here....

http://telecomanddata.com/poodle_jacket.jpg

[zrob_12]

When I went to bed last night, it was 22F and everything was still up. When I woke up this morning it was 16F and like I stated all the NS5s were offline. As the sun came out, they slowly started coming back online. Sure enough the ones with better signals came on first. However, some of the PS5s had worse signals then all of the NS5s, but were never offline.

Do you think my best solution would be to use 18v power supply or 24v power supply? Or would it best to just replace the NS5s with PS5s?

[WHT]

ok...if they started coming back on line after it warmed up, I'm gonna rule out a temperature inversion as the sun warming effect doesn't appear to start until at least an hour after sunrise, and even then...it would only affect some of the units (mostly the further out ones).

As to why the closer units came back online first..perhaps the cold was reducing the power levels with a 12 volt power supply. Mike Ford would know more about that.

[UBNT-Mike.Ford]

Hey Zrob,

Are the PoE injectors outside or the Plug for the wall?

I have done extensive cold weather testing and have not seen issues like this. Also are these units in 5Mhz mode?

Let me know.

Thanks,

Mike

[zrob_12]

All POE injectors are and power packs are inside.

Units are in 5Mhz mode.

Longest cat5 cable from POE to NS5 is 50ft, but most are about 20ft.

[zrob_12]

An update on this topic:
Late last night (around midnight), all NS5s slowly once again went offline (temp was 20F).
I woke up this morning (around 7:00) and all NS5s were back online (temp was 14F). However, we did not have a hard frost like we did yesterday. Now I'm really confused...

[UBNT-Mike.Ford]

Hey Zrob,

So they went offline at 20F but came back online at 14f? Is it possible to move these units to 10Mhz bandwidth?

Thanks,

Mike

[guidonet]

You do not forget to control the atmospheric pressure, is very important.
When the reception signal is low the atmospheric pressure is critical so that the microwaves propagate.
We have experienced cuts with our clients with temperatures superior to 20ºC but with low atmospheric pressure and low humidity.
By the way, whereupon signal level is registering your NS5.
The line of sight is cleared?

[zrob_12]

Mike, that is correct. I can move the units to 10Mhz, but I will have to do a couple things first. If I move one to 10Mhz, I have to move all of them correct?

[zrob_12]

Clear LOS to all units

[kijoma]

When I went to bed last night, it was 22F and everything was still up. When I woke up this morning it was 16F and like I stated all the NS5s were offline. As the sun came out, they slowly started coming back online. Sure enough the ones with better signals came on first. However, some of the PS5s had worse signals then all of the NS5s, but were never offline.

Do you think my best solution would be to use 18v power supply or 24v power supply? Or would it best to just replace the NS5s with PS5s?

As tommy cooper (uk comic) once said "Doctor it hurts if i touch here, here and here, whats wrong?", Doctor: "you have got a broken finger" :lol:

Have you considered that the problem maybe the receiver or transmitter in the AP that these clients connect to , if it has a cold problem and its sensitivity or power falls off then clients will drop in order fo signal strength :)

[zrob_12]

I have considered that it may be the AP, but I have 2 PS5s that are connnected which have signals far worse than the NS5s. These have not dropped.

[zrob_12]

Units are now set to 10MHz, I'll let you know my results.

[UBNT-Mike.Ford]

Any update?

Thanks,

Mike

[zrob_12]

All the units are still up so far. However, the temp hasn't dropped below freezing since I made the change.

The more and more I think about it, kijoma might be right - the problem might lie with the base and not the NS5s. The main reason I think this is because when one of the NS5s went down we replaced it with a new one that we had already configured and it too would not register with the AP. This unit came out of our office and wouldn't have had time to "get cold" yet. What does everyone think?

[guidonet]

More details about signal in both ends for units who leaving and who remains. CCQ-Gain-Variations... it must be useful

[zrob_12]

All PS5s remained connected:
1.) RSSI=20 CCQ=80-100%
2.) RSSI=44 CCQ=50-100%
3.) RSSI=24 CCQ=70-100%
4.) RSSI=25 CCQ=80-100%

All NS5s went offline:
1.) RSSI=40 CCQ=100%
2.) RSSI=30 CCQ=100%
3.) RSSI=26 CCQ=80-100%
4.) RSSI=25 CCQ=80-100%

[guidonet]

Sorry, but tell me about the other side.... tell me what happen with signal previously at the fall down.

[zrob_12]

All PS5 numbers remained the same, while all the NS5s were not even connected.

[guidonet]

The PS and the NS are in similar leases?
We experienced something similar in countryside, but it was not temperature problem, but that when the sun was hidden, we lose link with some of our clients, after hours began to appear.
The problem was single electrical, due to the increase of consumption, lowered the tension and let connect.
Soon it lowered the electrical consumption and it raised again the tension.
Perhaps the tolerance to the variation of electrical tension is better in the PS.

[rockhead]

I've got eight NS5's working at -29°C (that's -20 for those of you still using cubits to measure distance) and they are working just fine.

I suspect your problem is not the nano's.

Glenn

[UBNT-Mike.Ford]

Hey Zrob,

Any more info?

Thanks,

Mike

[zed]

Guys,

I have used Nanos on a Site and the two of them had gotten
moisture on them and failed..

Has anyone seen this? Is there a problem with the case?
If you look at the back of the radios where the LEDS are you can see the moisture there.

This is the caribbean..Temperature never drops below 55 f in this site, but regularly rains

Regards

[kijoma]

hi,


sounds like humidity is your enemy, as with all radio installations, if you live in a warm humid environment then (before they get wet inside) you will need to seal around the cable flap and cable entry hole.

Perhaps put a fresh small bag of silica gel inside there too before you do that.