this post was submitted on 17 Feb 2025
28 points (100.0% liked)

Ask Electronics

3476 readers
1 users here now

For questions about component-level electronic circuits, tools and equipment.

Rules

1: Be nice.

2: Be on-topic (eg: Electronic, not electrical).

3: No commercial stuff, buying, selling or valuations.

4: Be safe.


founded 2 years ago
MODERATORS
 

So I'm not sure what the right community for this is but I'm hoping yall can help. I'm a refrigeration service tech and recently I was tasked with replacing a sensor in a room used to store ethanol drums. Due to the nature of the room every device in it had to be rated explosion proof and I couldn't use any tools that could pose any risk of ignition (no heat gun, basically nothing with an electric motor, and definitely no open flames) while working in there. Normally when I splice wires I use heatshrink to cover the splice simply because it looks far more professional than electrical tape and it holds up better over time. However in this case I could not figure out any way of shrinking said heatshrink without posing a potential ignition hazard so I was stuck just wrapping the splice in tape. We do a lot of work for this company so I'm hoping to find a better solution for the next time I am in a similar situation.

So do any of you know any way to shrink heatshrink without posing an ignition hazard or am I stuck just using tape in those situations?

top 29 comments
sorted by: hot top controversial new old
[–] [email protected] 43 points 4 days ago (3 children)

Maybe you can get your hands on cold shrink tubing? It's a rubbery tube stretched over a plastic frame thingy. You pull the frame out and the rubber shrinks down. No heat needed.

[–] [email protected] 11 points 4 days ago* (last edited 4 days ago) (1 children)

Posts like these are why Lemmy will surpass Reddit. ~~No ads~~, no bullshit. Thank you for posting this answer!

[–] [email protected] 5 points 4 days ago

I mean, I kinda did post an ad as an example, lol. But it was the most concise video I could find in like 30 seconds of looking! I am in no way shilling for whoever the company was. Any cold shrink brand will be more or less equivalent.

And you're welcome! I do like being helpful in areas I know things about.

[–] [email protected] 8 points 4 days ago (1 children)

I had never heard of that. Definitely going to look into it now though.

[–] [email protected] 3 points 4 days ago

If you can't source that, you could use EPR tape

[–] [email protected] 3 points 4 days ago (1 children)

It's very expensive, but it would probably be the best option when you can't use heat.

[–] [email protected] 8 points 4 days ago

In this case they can pass the cost onto the customer. The higher restrictions will always result in higher costs, so they're probably used to it.

[–] [email protected] 9 points 4 days ago (1 children)

I don't think there's any way to safely generate just enough heat for this to work without the ignition hazard. Heatshrink definitely looks nicer than tape but I think anyone will understand in this scenario.

[–] [email protected] 4 points 4 days ago (1 children)

Yeah, tape is fine here and logically I know noone will complain but it still rubs me the wrong way so I was hoping there was an alternative. If not then oh well, tape it is.

[–] [email protected] 3 points 4 days ago (1 children)

Have you seen self adhesive tape? It's a bit nicer at least.

[–] [email protected] 2 points 4 days ago

Yeah, I'll have to bring some of that along next time. We have it at the shop. I just didn't consider bringing it last time because it hadn't occured to me that heat shrink would be impossible to use in there until I was nearly done.

[–] [email protected] 7 points 4 days ago

Liquid electrical tape

[–] [email protected] 8 points 4 days ago (4 children)

Some PVC tubing will start to shrink around 70°C. Can you get boiling water to it fast enough before it cools?

[–] [email protected] 7 points 4 days ago

A thermos might work!

[–] [email protected] 5 points 4 days ago

There's an idea. As long as I'm using boiling water there will never be an ignition hazard because it will never go much above 100C. I could probably do something with a bit of water and quicklime to have an instant ignition free hotplate.

I'd need to figure out specifics and test it elsewhere of course but that is probably workable. The real question is if it's practical in the field. Either way it's something I'll probably try out at home just for fun.

[–] [email protected] 4 points 4 days ago (1 children)

This is what I would think...

Wear heat resistant gloves, boil two spoons in something (an electric kettle perhaps), take the spoons into the room, spoon them over the heat shrink.

... failing that there's always automotive electrical tape.

[–] [email protected] 2 points 4 days ago (1 children)

That's one very roundabout way to transfer heat when one can just bring it in with water.

[–] [email protected] 1 points 4 days ago

That's a good point... As long as it's not going to effect anything else around, and exploding or hot water isn't a risk factor.

[–] [email protected] 2 points 4 days ago

Maybe some air-activated hand warmers? This page says they can get up to 70°C, although they average 57°C. Maybe that would be enough, using several?

[–] [email protected] 6 points 4 days ago

There are explosion proof hot plates for lab work, you could get one of those or something similar.

[–] [email protected] 4 points 4 days ago

Would self amalgamating tape work? You have to stretch it and wrap it fairly tight, which can be fiddlyvon small diameters, but it'll seal the joint and doesn't peel off and get nasty like electrical tape.

[–] [email protected] 4 points 4 days ago (1 children)

Wait... How are you splicing the wires? Crimped butt splices?

[–] [email protected] 2 points 4 days ago (1 children)

In this situation it was butt splices. We almost never solder anything. We just need the butt splices sealed in case of condensation or dirt.

[–] [email protected] 9 points 4 days ago (1 children)

Ok, thought so. Another option is gel splice covers. They're a plastic box with waterproof goo in them to cover the connection. This is just one example, but there are plenty. Wago sells some specifically for their splice connectors. There are also some where you mix your own goo, but I've never seen or used them.

[–] [email protected] 7 points 4 days ago (1 children)

Of course! I've actually used those for marine connections before. For some reason I just forgot those existed. Thank you.

[–] [email protected] 3 points 4 days ago

Context is a fickle mistress like that. I have deffo overlooked options because the surroundings were different.

[–] [email protected] 3 points 4 days ago (1 children)

How about heating up a soldering iron outside, turnoff and unplug then take it in and use the residual heat?

[–] [email protected] 1 points 4 days ago (1 children)

I don't think a soldering iron would retain enough heat. I had considered warming something else up with a torch but any hot work anywhere in that site requires all sorts of permitting even where it's possible.

[–] [email protected] 2 points 4 days ago

The options from other responses are better (gel, cold shrink tubing), but just for your edification, sand in a box can work as an extremely effective insulator for a short period. So heat up the soldering iron and stick it in a bed of sand in a box to take it in with you. Most of the heat won't escape the box, but it will spread through the tool, so you'll definitely want gloves.