More Jam Jar Nonsense :)

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To get rid of the condensation you could bake it and then fill it with nitrogen instead?

It's a bit extreme but it's what we used to do with avionics ✈

 
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As it's a jam jar it's already " baked " but am not sure that's what you meant? Also making it properly air tight may be difficult!?

Gonna give it a long test tonight to see how much water forms then try again tomorrow with some silica.

Any other advise is greatly appreciated.

:)

 
Ok.. Heres what we used to do..

Our instruments were put in an oven and connected to a vaccuum pump, after they had been in there a while (some up to 4 hrs) they were filled with nitrogen, purged again and refilled with nitrogen again. Then the instruments were sealed.

 
If you warm the jar up before sealing it will expel damp air - warm air is drier,  and in effect creat a small vacuum -- should be sufficient to remove most condensation issues without getting complicated.

 
But then when the lamp is on and heat generated it will cause a vacuum in the jar which will then draw in moisture/air where it can. The stuffing gland on the back it the prime location, or even the lid.

As sidewinder said you can get glands that stop vacuum.

 
Ok.. Heres what we used to do..

Our instruments were put in an oven and connected to a vaccuum pump, after they had been in there a while (some up to 4 hrs) they were filled with nitrogen, purged again and refilled with nitrogen again. Then the instruments were sealed.
Yes.. As I suspected, a bit more complicated than is possible at home. But thankyou anyhow :)

Sidewinder. I found some screw type plastic vents is this what you meant? Also I haven't found a source of less than 5000.

Binky, will give that a go but am not sure I can make it fully air tight with the compression gland and the cable poking out the top?

 
Yes.. As I suspected, a bit more complicated than is possible at home. But thankyou anyhow :)

Sidewinder. I found some screw type plastic vents is this what you meant? Also I haven't found a source of less than 5000.

Binky, will give that a go but am not sure I can make it fully air tight with the compression gland and the cable poking out the top?
My corner shop may be able to assist........

EN83188

JDAE12PA/SW

HYLEC

VENTING PLUG, IP66/IP69K, BLK, M12

Accessory Type:Venting Element; For Use With:Enclosures; SVHC:No SVHC (16-Jun-2014) ; AF Size - Metric:17mm; Colour:Black;

In Stock

Price For: 1 Each

1+ £3.67 (£4.40)

10+ £3.48 (£4.18)

50+ £3.30 (£3.96)

more

EN83189

JDAE12PA7035

HYLEC

VENTING PLUG, IP66/IP69K, GREY, M12

Accessory Type:Venting Element; For Use With:Enclosures; SVHC:No SVHC (16-Jun-2014) ; AF Size - Metric:17mm; Colour:Grey;

In Stock

Price For: 1 Each

1+ £3.67 (£4.40)

10+ £3.48 (£4.18)

50+ £3.30 (£3.96)

more

Just saying

 
Thats the jobbie Kerch , thanks :D

I kept getting Chinese suppliers, Must have googled the wrong thing. :(

Not cheap, probably more than the whole lamp as is. never mind.

:)

Ordered....

  •  VENTING PLUG, IP66/IP69K, BLK, M12
  •  Accessory Type: Venting Element
  •  For Use With: Enclosures
  •  SVHC: No SVHC (16-Jun-2014)
  •  AF Size - Metric: 17mm
  •  Colour: Black
  •  Thread Length: 10mm
  •  Thread Size - Metric: M12
  • Protection for hermetically sealed electro-technical and electronic enclosures
  • Protects against condensation water from alternating temperature and pressure
  • Pressure, continuous ventilation and adaption of the inner pressure
  • Hydrophobic and oleophobic PES-membrane
  • Body: PA6
  • O ring: nitrile rubber
  • Membrane: polyether sulphone PES
  • Typical air flow: 90 to 130ml/min/cm²
  • Protection grade: IP66
  • Operating temperature: -40°C to 100°C

Now I know why they aren't cheap, they've got rabies!  :slap

 
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Respect!

Duckie, PM me your snail mail address and I'll send you an (immersion proof) breather to try. I use them all the time for external enclosures to assist with...............well breathing! Work a treat.

Vomiting on a 'cappa? NO RESPECT!  :lol:

 
But then when the lamp is on and heat generated it will cause a vacuum in the jar which will then draw in moisture/air where it can. The stuffing gland on the back it the prime location, or even the lid.

As sidewinder said you can get glands that stop vacuum.
warm air expands so won't cause a vacuum, when it cools again it may draw a little bit back in depending on sealing, but it is unlikely to suck much mositure in and any heat will help dry things out.

 
warm air expands so won't cause a vacuum, when it cools again it may draw a little bit back in depending on sealing, but it is unlikely to suck much mositure in and any heat will help dry things out.
That information was provided to me from Hunza Outdoor Lighting with regard to why some outdoor lighting fittings although perfectly sealed had water inside.We have been called to so many garden installs with ingress of water in the fitting some with an inch of water.

 
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I know of an outdoor lighting transformer that says it should not be mounted outside below any water level (or something like that) as when in use the air around it will expand (no problem) but when it cools it can create a vacuum sucking in water which will damage the unit over time.

 
That information was provided to me from Hunza Outdoor Lighting with regard to why some outdoor lighting fittings although perfectly sealed had water inside.

We have been called to so many garden installs with ingress of water in the fitting some with an inch of water.
Think about it - unless the volume of the fitting was huge then the air couldn't hold enough water vapour to produce an inch of water.

It's not sealed. It's leaking.

 
That information was provided to me from Hunza Outdoor Lighting with regard to why some outdoor lighting fittings although perfectly sealed had water inside.

We have been called to so many garden installs with ingress of water in the fitting some with an inch of water.
Hunza have obviously never studied Physics then. If you have an inch of water in the fitting, then it's leaking. I used to build Naval weapons, including torpedo tails, there's not much about sealing equipment I haven't come across. We fitted Hunza ground lights in Salcombe last year,defo no moisture in them this year. Biggest culprit for water ingress is dirt on the seals, very hard to avoid on a building site or generally surrounded by dirt. it also helps if you allow for drainage around the fitting, ie soak-away principle.

 
The Hunza fittings are fine and they have the black plastic connector about 150mm from the fitting, when I enquired what it was for, I was told it was to stop moisture getting in the flex and into the fitting.

The spike lights we have been called out to had been pushed hard down into the ground and gland is in the ground, the tops are sealed and fine, we have pulled the fittings up and out of the ground it cured the problem.

Now these fittings could be any make, but we always fit Hunza so that's why we asked what could be causing it, they explained and added that's why they have the inline anti whatever to stop ingress.

Seemed logical to me and what they suggested worked, but it may have been bull, so who knows.

 
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 so the issue was a fitting deisgned to be above ground level had been pushed into the ground, so basically you would need a gland that could withstand being immersed ie IP 70 something.

What heat from lamp can cause is expansion of the air within the fitting, if this leaks out, then when the lamp cools it could possibly cause a small vacuum, and draw damp air back into the fitting. If the fitting is at ground level, then it is potentailly possible to suck in water and fill your fitting up!

 
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