Do FTTC cabinets still hum when live?

The reason I ask is because we have two cabinets in our area, both been in for a while and both showing on the checker as taking orders. However neither makes any noise, certainly no humming even at a foot away. So, are newer cabinets silent or has the checker jumped the gun?

No, they are not allways audiable when live. I believe the cooling fans are variable so may not even run when the ambient temperature is not high enough and the power load is realatively small.

Have you tried putting your ear against the cabinet, about one third of the way done from the top on the left-hand door of a two door cabinet? Depending upon ambient noise, there is usually some indication that the electronics are "powered up" even if the fans are not currently turning. The fans produce a mechanical noise / swish, the electronics (more succinctly the mains transformer) can hum.

Having said that, I do agree with Ribble's comment. You could be experiencing a very quiet pair of cabinets.

I would have thought they would all hum, at least from time to time. After all, it must get pretty boring standing at the side of the street day in day out - they would need to do something occasionally to relieve the boredom and humming a cheery little tune might just do the trick!

Since it is colder now less need for the fans as well

Makes sense then as there was no noise from either (even a hum) but then I was just passing and didn't listen too hard as I thought it would be louder than it might. One definitely felt warm on the top of the door where I leaned, so that also makes sense if the fans only come in to effect when the temperatures require.

You do need to get your ear down near the cooling vents to hear it.

In reply to a post by wirelesspacman:

I would have thought they would all hum, at least from time to time.

It may depend on the diet of the local dog population.

Going off at a tangent a little, but one our local cabs was re-shelled. I don't think it's a FTTC cab - it only has two small vents low down on each of the side panels - but am curious as to why. It's very close (200 m) to two new FTTC cabs, and a new 'twin lid' pit, but the cab is only down as FTTC. When the new pit was built I thought maybe it was for FTTP, but am I right about the cab?

A re-shell is either done due to damage or to increase the termination capacity. This might be in order to add the connection strips that terminate the link cable between the PCP and FTTC cabinet