Smallest Enclosure Face

[Sidewinder]

Well, I need to get 36 off CW20s glands into the bottom of an enclosure!

The box has not yet been purchased, the glands can be fitted one at a time, and as far as removal at a later date goes, we may have to tackle that one if it comes along!

Any suggestions, I'm thinking 3 rows in a sort of a vee formation?

gland

         gland >>>>>

gland

Multiplied 12 times along the box

I think this would be the most compact arrangement.

Anyone any better geometric suggestions?

How close together do you think we could get the glands?

I guess allowing a diameter 50mm circle for each gland and having the circles touching would be the smallest layout?

Anyone else?

We may need a custom enclosure but we are not worried about that at this stage to be honest.

Oh and the enclosure is not for power it's for data, not that that matters to be honest.

The cost of a custom box will be insignificant in comparison to the 1km of 1.5 2c SWA, the 3km of Cat6 SWA etc.

 

[alpha spark]

Could u use a length of trunking bushed to the enclosure or is there not enough space

 

[steptoe]

Id say you are about right on th formation,

Last time I needed to do something similar I used some 4" galv trunking spotted at th top with ends fitted, meant the enclosure could b lot smaller than the glanded face.

 

[Sidewinder]

The assembly needs to be > IP55, hence the CW glands, so no trunking!

Also I need to get 100 wire end terminations in there anyway, so in the end the enclosure may be bigger than needed.

I'll lay it out in CAD later to see.

 

[Evans Electric]

Off the Top of the head guess   ,  enclosure 500mm wide   X  120mm deep  (min)  X however height you need .   If its data , do you need  to fit the banjoes ?

 

[Sidewinder]

Just run it out on CAD with touching 50mm circles, it will be 1mx200mmx height, say 150mm.

The length surprised me, I could sacrifice length for width, but, in this situation I would rather keep it close to the wall.

It may well have at least a Unistrut barrier around it once installed!

 

[Marvo]

With that number of SWA cables maybe you should look at marshalling cabinets instead of standard enclosures, you can mount a gland plate internally at an angle to reduce the width or depth footprint of the enclosure.

 

[kerching]

If it was me I would get 3 banjos , does not really matter if you are going to actually use them or not. Nut and bolt through the three holes, spread out into a Y formation so the top two banjos are just separate (make sure locknuts fit...lock rings may be better)

Use this as a template...inqvert the banjo and repeat. I think 50mm may be too generous ...just saying

 

[Evans Electric]

I thought 50mm was overkill  too TBH  .  You can get 20mm glands quite close together ,  tighten the l/nuts up with a small chisel .   I thought about  45mm centre to centre . 

Have to be honest , what I normally do is  place all the locknuts in row  and go from there. 

 

[Sidewinder]

Thing is guys, the 50mm is the circle inscribing the lock nut, no banjo's are required as there is no real need for earthing the SWA.

The completed unit has to be IP55 or above, hence Marvo, I had not considered what I've seen called a marshaling cabinet.

A 20mm gland lock nut is 42mm across corners according to the BS for the item, so I have to allow this as we could have lock nuts made to standard!

Thus each gland needs at least a 42mm diameter circle around it.

Allowing 4mm between each nut on radius corner to corner did not seem excessive to be honest.

I can move them closer together but that will increase the depth of the enclosure from the wall, thus it is more likely to get damaged.

Its only possible location was on Thursday buried inside over 100 cubic metres of paper & card recycling!

 

[kerching]

I thought 50mm was overkill  too TBH  .  You can get 20mm glands quite close together ,  tighten the l/nuts up with a small chisel .   I thought about  45mm centre to centre . 

Have to be honest , what I normally do is  place all the locknuts in row  and go from there. 

I sometimes use this method. But then substitute the locknuts for rings...I like lock rings .

I read somewhere a while ago about Niccy going all moody and deducting 1 jimmy savile point if locknuts were tw@ted up with a chisel or other percussive driven instrument...just saying

 

[Sidewinder]

Point taken Kerch, but, there is still the diameter of the gland itself to consider, and lock rings have less of a machanical bearing face on the enclosure to support the gland in the event of external mechanical forces on the enclosure/gland interface.

See my last post!

 

[Marvo]

Outdoor marshalling cabinets should all come at IP55 or better. I was thinking of a ground mounted type with a plinth area so the gland plate can be arranged at an angle inside. It could also be hard against a wall and it saves capping the incoming cables as well.

 

[Sidewinder]

Marvo,

It has to be wall mounted, it will be about 1.5m above ffl.

The cables will all enter from the bottom curve around and run up basket to one side for about 5m before they go off around the premises.

 

[Marvo]

Okay, if it's 1500 affl then it was a bad suggestion. 

 

[Sidewinder]

Marvo,

Not bad mate, you have not seem the job!

An alternative which is what I asked for.

 

[kerching]

Point taken Kerch, but, there is still the diameter of the gland itself to consider, and lock rings have less of a machanical bearing face on the enclosure to support the gland in the event of external mechanical forces on the enclosure/gland interface.

See my last post!

Whoops never saw your post, mr Shiraz called

 

[Marvo]

Could you reduce the space between the glands by using (probably the wrong term) a slogging nut. We used to get SWA glands with a nut that had a castle shaped outer edge rather than the standard hex nut. They had a considerable smaller diameter than the hex type nuts and could be tightened using a C-spanner.  

 

[Sidewinder]

A knurled lock ring has been suggested, but the OD & bearing faces are quite small, thus a reduced mechanical interface strength.

Not seen a nut as you describe on a gland, but I have on many other things done up with a hook spanner like this?:

http://www.wixroyd.com/en/catalog/standard-parts/hand-tools/hook-spanners/95100

I'm not sure that 1m is too much for 25 off 12mm diameter SWA cables coming into an enclosure TBH.

I have to terminate these into 100 points and send them back out on 2x25 pair duct grade Cat6's @ dia 15mm in stuffing glands, so this option will keep me close to the wall and give me room to work in case of re-configuration if I leave enough slack in the cores to reach either end of the enclosure.

I am allowing for some, future expansion BTW!

 

[sellers]

I think 50mm is about right, leaving a 50mm diameter around means there is still 50mm from centre to centre of each hole.  Allowing for half of each of the 2 glands, say roughly 13mm each (with the banjo and shroud) and your left with 24mm between each gland.