Grommets/glands for box?

[Discharged]

Hi

I'm looking to install a switch into a box like this one:

... and so will require a lead going in and one coming out. I need to find a way to hold the leads in a safe and secure manner, but don't want to/can't use 20mm glands - they'd look ugly in this, and are just wrong I think. But I'm pretty sure that I have seen something like grommets which you would slide over the top of the cable and located in a hole that was cut into the box. I imagine that the box will be split horizontally, and the hole for each cable will be centred on that split line of the casing.

Can you see what I'm trying to ask about here? Where can I get a grommet that could hold a 1.5mm twin + earth, and sit on one half of the casing, and then put the other half of the casing on top and screw it down?

I think I need to know the name of the item, so that's where I'm a bit stuck. I can find some grommet-like things on RS Online, but I'm not convinced they're what I need. I think I want something that is probably no bigger than perhaps 5mm long?

Anyone help, please?

 

[Discharged]

Here's the one (with a cable clamp):

 

[Discharged]

I'd use the strain relief grommets as shown on the Maplin site but NOT on a cut line in the casing / box unless no other option.
If you're using 1.5 T&E you'll need a large grommet as they work by putting a 'kink' in the cable within the body of the grommet so you get cable prtection and cable security.

Lofty.

Thank you. It might turn out that the stat is taller than I am anticipating and this would demand a correspondingly taller box - thus permitting the gland to be located in solid wall and not on a joint line.

 

[clicon357]

Try Toolstation part number 86064, their "Choc Box". Many like this that include strain relief at each end. I wonder if instead of of the connector block you could fit your thermostat in it's place?

(Appreciate that its translucent and might not fit the bill aesthetically but you could always spray it black...........as its Christmas why not go the whole hog and choose a glitter finish from the Plasti-Kote range!)

 

[Discharged]

Hm, not quite the aesthetic I was seeking - and the IP is too low for my liking. It really needs to be up around 65 or 67.

I like the idea of spray painting it, however! Maybe a nice shade of pink?

 

[Marvo]

Not in itself, no. It looks like this:

You can see that it has two mounting holes, but if the casing does not allow, then I might have to find another way of securing it in there - No More Nails, for example. Again, if the casing permitted, then I might be able to fit a couple of cord grips.

Finally, to waterproof and protect the unit, I aim to fill it with potting compound/liquid rubber, from underneath where there will be room having cut a hole for the stat.

The 'thermostat' you have shown is supposed to be mounted against the metal surface of a tank or cylinder etc and there's usually heat paste applied between the surfaces to improve the accuracy. I don't understand how you're going to mount this in a plastic enclosure. How is it going to work? What is it going to sense the temperature of if it's closed up in a box?

I'm guessing the 'no more nails' comment indicates this post is a wind-up.

 

[Discharged]

Now there is something funny! No, no 'no more nails'! It has holes for fixing, and I'll need a box with posts a suitable distance to fit. Marvo, there will have to be a hole of the correct diameter to allow the stat to protrude and make the necessary contact - it's not going to be hidden away inside the casing, promise. I should have made that clear. The heat paste thing sounds interesting. I guess you mean the same stuff to fix heatsinks in place on a CPU?

 

[Specialist]

Hi Discharged: You can buy small kits of posts / screws from Maplin or Rapid Electronics so you can put the holes / mountings to suit yourself. Just checked a number of thermal switches like the 1 you show & all are about 15mm deep, for those type switches as long as you have solid contact with whatever your monitoring you should'nt need thermal transfer compound. If you do decide to use it you can buy small tubes from either of the above suppliers.

 

[Marvo]

The heat paste is optional, it depends on the application and how fast its response needs to be. This type of heat sensor usually mounts on two spot-welded threaded pins, 2 nuts keep it tensioned against the object it's sensing. If there's no mounting system already there then you're kinda in the twilight zone. It's going to be difficult to maintain the necessary tension.

 

[Discharged]

Thanks for the tip re posts/screws - I'll jump over there for a peek. Do you think these stats are any good at detecting air temperature, from what you know of them? Not that I'm planning on using one like that, I'm just curious.

 

[Discharged]

The heat paste is optional, it depends on the application and how fast its response needs to be. This type of heat sensor usually mounts on two spot-welded threaded pins, 2 nuts keep it tensioned against the object it's sensing. If there's no mounting system already there then you're kinda in the twilight zone. It's going to be difficult to maintain the necessary tension.

If the casing were cable-tied to the object it's there to monitor, would that be sufficient do you think, Marvo?

 

[Marvo]

I don't think they'd be good at measuring air temp unless it was sitting in a strong airflow, I think the response time would be too slow.

A cablestrap might work if the temp wasn't too high.

 

[Discharged]

This one is for the opposite - to detect low temps.