Probable Overheating Street Cabinet

Rimmer100 · 03-06-2009, 10:21

Hello,

I think I am suffering from the dreaded Green Cabinet Overheating issue and I was wondering if anyone has any ideas of how best to raise this with VM.

The installation is only a few months old, so new cable was run to the flat. I had noticed that toward the end of the day the 'Online' light on my V+ box would start flashing. Didn't think anything of it until Sunday afternoon when it was the first truly hot day of the year and I lost my broadband as well. (It had been working in the morning). The ready light was flashing and the modem was dishing out a 192.xxx.xxx.xxx address as it couldn't talk to the servers.

I duly phoned VM after checking there weren't any outages in the area. I spoke to the broadband operative who decided that my modem was clearly faulty. Clearly. He wasn't interested by the fact that the V+ box wasn't 'Online' either. So I made the appointment later in the week knowing full well by the next morning everything would be fine. Low and behold the next morning, once everything had cooled off, I had broadband again.

Yesterday the same thing. Got home from work when the cabinet had been toasting itself and I had no broadband. Left to do some stuff, came back at 9PM and the broadband was back up. It seems the V+ box is more sensitive as it generally doesn't sort itself out until some point during the night.

The modem was changed when they (finally) did the installation in February / March. It is completely open to the air and doesn't get that hot.

What is the best way to get VM out to check the cabinet? I really don't want to have to take time off work for them to come and not see a fault because it happens to rain, when they just need to check their cabinet in the street.

The cabinet is situated in a position where it takes full advantage of getting baked all day.

Would wrapping the cabinet in tin foil help to reflect the heat, thus keeping it cooler and give passer's by something to laugh at or would strapping a garden parasol to it be better? Would dousing the cabinet with water, cool it down sufficiently to prove my point?

Any suggestions would be gratefully received.

This used to be an NTL area by the way.

Graham M · 03-06-2009, 10:27

Are any of your neighbours experiencing the same problem?

Rimmer100 · 03-06-2009, 10:32

That's a good point I haven't checked. Not entirely sure how many, if any, are VM customers. What with having to get way leaves from the landlord to get it installed they probably stick to ADSL.

I'll do some asking.

on in an hour! · 03-06-2009, 10:47

hi,
check at the back of your equipment to see if theres 1) a forward path attenuator 2) a cable simulator or 3) an equalizer coloured purple/green/or orange in that order,if there is remove them in the heat (this will enhance the signal level) but remember to replace them in normal weather.the amplifier in the cabinet is heating up to such a degree that the signal levels are dropping,hence your online/rdy lights are flashing.

Joxer · 03-06-2009, 13:48

Try checking the power levels on the modem when it's not working against when it is - in particular the upstream level anything over 55 is not so good.

Rimmer100 · 03-06-2009, 20:34

Thanks for the tips. I don't have any attenuators on this setup, just the standard splitter for the cable modem and V+ box.

I'll have a look at the levels today (as it is nice and cool and everything is working as it should) and compare it to the next time it gets hot and goes all funny.

I've checked with a neighbour and they are having difficulties but theirs sound completely different to mine. They've got problems with their TV signal as well, where as mine has been fine, even when I've had the problems. They were also told that there had been known issues in the area, but nothing has been logged on the website.

I'll update you the next time it gets hot, if things fall over.

Rimmer100 · 03-06-2009, 23:49

For completeness here are my 'cool' modem levels:

Cable Modem Upstream
Upstream Lock : Locked
Upstream Channel ID : 2
Upstream Frequency : 29200000 Hz
Upstream Modulation : QPSK
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 51.0 dBmV
Upstream Mini-Slot Size : 2

Cable Modem Downstream
Downstream Lock : Locked
Downstream Channel Id : 1
Downstream Frequency : 330750000 Hz
Downstream Modulation : QAM64
Downstream Symbol Rate : 6952 Ksym/sec
Downstream Interleave Depth : taps12Increment17
Downstream Receive Power Level : -7.2 dBmV
Downstream SNR : 27.4 dB

moaningmags · 03-06-2009, 23:57

Your downstream SNR is too low.

techyguy4 · 04-06-2009, 03:35

Quote:

Originally Posted by moaningmags

Your downstream SNR is too low.

Not SNR but downstream power level is too low.

moaningmags · 04-06-2009, 04:31

Quote:

Originally Posted by techyguy4

Not SNR but downstream power level is too low.

SNR @ 27.4 is too low.

Joxer · 04-06-2009, 11:13

Quote:

SNR @ 27.4 is too low.

Seconded.

The upstream power is within limits but at the high end, it won't take much of an increase to take this too high.

Rimmer100 · 05-06-2009, 13:51

Guess I'll need to get an engineer out. It's been cold for a bit so I'll wait until the weather heats up and it stops working again. That is if the weather ever does heat up again!

Many thanks for your suggestions.

moaningmags · 05-06-2009, 15:34

Is your SNR still low or has it increased with the drop in temp?

Rimmer100 · 23-06-2009, 19:14

First hot day since I last posted, so my internet is out. Connecting via a mobile phone to post my 'hot' modem levels:

Upstream Lock : Not Locked
Upstream Channel ID : 2
Upstream Frequency : 29200000 Hz
Upstream Modulation : QPSK
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 61.0 dBmV
Upstream Mini-Slot Size : 2

Downstream Lock : Locked
Downstream Channel Id : 1
Downstream Frequency : 330750000 Hz
Downstream Modulation : QAM64
Downstream Symbol Rate : 6952 Ksym/sec
Downstream Interleave Depth : taps12Increment17
Downstream Receive Power Level : -7.4 dBmV
Downstream SNR : 28.4 dB

Guess I'm going to have to take some time off and get an engineer out. Unless you can buy the attenuators etc online so I don't have to bother

As before the online light is out on the V+ box too. Out of interest what does the V+ box use the network for? Is it just firmware updates etc?

Druchii · 23-06-2009, 19:23

Upstream looks massively high. SNR on downstream is below 30.

Looks wrong to me. However, i'm not 100% sure on thresholds.