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Topic Title: Emergency lights.
Topic Summary: Pressure equalizing bladder for IP 65 compliance.
Created On: 08 August 2014 10:33 AM
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 08 August 2014 10:33 AM
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Avatar for Zoomup.
Zoomup

Posts: 666
Joined: 20 February 2014

I recently installed a new LED emergency light and was surprised to find a small bladder inside the fitting with a label saying that the device was installed to allow for air pressure build up internally when the temperature rises, thus ensuring IP65 compliance. Presumably the bladder compresses if the fitting is totally sealed, thus absorbing any air pressure increase. Also it removes the partial vacuum created when the temperature drops thus preventing the likelihood of sucking in damp air.
Very clever I thought.
 08 August 2014 04:00 PM
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Avatar for OMS.
OMS

Posts: 19896
Joined: 23 March 2004

What make/manufacturer was it ?

Regards

OMS

-------------------------
Failure is always an option
 08 August 2014 04:40 PM
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Zoomup

Posts: 666
Joined: 20 February 2014

Originally posted by: OMS

What make/manufacturer was it ?



Regards



OMS


Hello OMS,
the make is HiSpec. Batch:3739. Model HSEM/LED. Supply 220-240-50 Hz. 3.6. Volt 2 Ah. Ni-Cad.

Obtained from a wholesaler in North Norfolk. Symbols on box. F in a triangle with point downwards. CE. IP65 and RoHS.

Operating environment: -10 deg. C to +40 deg. C.

Lamp type: 50 X 5mm dia. LED.

Operating time: 3 hours.

Charging time: 20 hours average approx.

Case fire retardant polycarbonate casing, transparent diffuser, metal gear tray.

Unit is protected against supply voltage polarity reversal.

The instructions are o.k. but do not detail the use of the internal link to achieve maintained or non-maintained outputs. The installer needs to work this out for themselves. The LEDs are a bit blinding and are very bright point sources. The plastic bag that comes with the emergency light fitting is useful for positioning inside the clear diffuser to act as an extra light diffuser to cut down glare.


It can be wired maintained or non-maintained. Cost just over £22.00 + VAT. It is similar to the BG type. The BG LED Emergency light can be wired for dim output maintained, which then gives full brightness upon mains failure.

Bye,

Z.

Edited: 08 August 2014 at 04:50 PM by Zoomup
 08 August 2014 04:50 PM
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OMS

Posts: 19896
Joined: 23 March 2004

Thanks - it was the "aspirating" feature you mentioned I was interested particularly in - I'll take a look

Regards

OMS

-------------------------
Failure is always an option
 08 August 2014 04:53 PM
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Zoomup

Posts: 666
Joined: 20 February 2014

Originally posted by: OMS

Thanks - it was the "aspirating" feature you mentioned I was interested particularly in - I'll take a look



Regards



OMS


The aspirating feature is not mentioned in the instructions, but looks like a small inflated balloon about the size of a large garden pea.
 08 August 2014 06:12 PM
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OMS

Posts: 19896
Joined: 23 March 2004

OK - I'm guessing it must be "robust enough" to re inflate as the luminaire internal pressure drops with temperature - it was something we played about with a while back but for switchgear cabinets

We had a diaphragm across a nitrogen filled vessel to try and accomodate the expansion without defeating the door seals

We gave up in the end in favour of letting the cabinets breath and adding a small DX aircon system to maintain cabinet temperature and (to some extent) humidity

Regards

OMS

-------------------------
Failure is always an option
 08 August 2014 09:20 PM
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keylevel

Posts: 482
Joined: 31 October 2003

We've used things like this (but also with a desiccant) in the past for electronics enclosures (radar signal processors).
 21 August 2014 12:42 PM
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bigtrog

Posts: 1
Joined: 21 August 2014

Originally posted by: keylevel

We've used things like this (but also with a desiccant) in the past for electronics enclosures (radar signal processors).


yes, this is what came to my mind too...
 21 August 2014 01:22 PM
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Avatar for OMS.
OMS

Posts: 19896
Joined: 23 March 2004

Thanks chaps - I've used pressure equalizing valves previously but a useful reminder al the same

Regards

OMS

-------------------------
Failure is always an option
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