"clever" gas detector. Advice please

[sarabande]

\"clever\" gas detector. Advice please

I have a simple Lidl gas detector from a forum posting some time ago, but want to put in another one.

Any practical recommendations for one which can deal with a diesel spill as well as a gas leak, and which might be able to take multiple detector heads ? 24v and 12v systems available.

thanks, team !

 

[VicS]

Re: \"clever\" gas detector. Advice please

They won't detect diesel spills will they? As far as I know they only detect flammable vapours.

 

[sarabande]

Re: \"clever\" gas detector. Advice please

I wondered, but diesel gives off volatile hydrocarbon vapour, which is why I'm looking for experienced advice.

I'll post if I find out anything. thanks

 

[Sy-Revolution]

Re: \"clever\" gas detector. Advice please

I use a Haztec system, can detect LPG and CO and supports 2 X LPG sensors and one CO sensor. Also shut gas valve (comes with a latching solenoid valve) off if leak is detected. Don't know about Diesel though but it did sound alarm when I used some squirty foam the other day.....

Not cheap but a good system.

http://www.whispaire.co.uk/haztec.html

no connection.......

 

[whiteoaks7]

Re: \"clever\" gas detector. Advice please

I made my own - have a look at the website - and one of the things I discovered when using the RS sensors was that they were sensitive to a number of gaseous products and that the sensor manufacturer went to some lengths to try to filter them only for the gas in question - just the opposite of what you want I guess - but it might be worth tracking down the manufacturer of the RS sensors (sorry I can;t remember who they are now) to see if they make a calibrated sensor that detects diesel. Let us know - it seems like a good idea.

I do find mine can be tripped by alcohol (but then, so can I) and spirit vinegar; I've never tried diesel though.

 

[wiggy]

Re: \"clever\" gas detector. Advice please

My gas alarm was set off by a large amount of washing up liquid that was spilt!!!! How Bizar

 

[VicS]

Re: \"clever\" gas detector. Advice please

[ QUOTE ]
I made my own

[/ QUOTE ] The Figaro detector supplied by RS is calibrated for methane and is specifically intended for use with domestic natural gas systems. While it will repond to other flammable gases and vapours, including ethanol vapour, it's calibration will not be correct even for butane and propane. If intended for use with LPG systems an LPG sensor should be chosen from the Figaro range. I note that there is one designed for methane and LPG

Data sheet here

and operating principle here


The Figaro website lists the range of detectors but none, as far as I can see, intened to detect spilt diesel.

I am a little surprised that the detector responded to vinegar, but since acetic acid vapour is flammable I suppose I should not be! Heaven knows why Wiggy's washing up liquid caused a response.

It is within the realms of possibility that these detectors will respond to diesel but it will probably require a fair spillage to produce enough vapour for it do do so and the sensitivity will be a totally unknown factor.

My thoughts anyway!

No comment about using the Vellman thermostat from RS but I would have thought a much simpler circuit would have been adequate to link a piezo alarm to the Figaro module. William_H any comment?

 

[oldharry]

Re: \"clever\" gas detector. Advice please

[ QUOTE ]
Iit did sound alarm when I used some squirty foam the other day.....


[/ QUOTE ]

Butane is often used as a propellant for aerosol cans. Not very clever if its to be used on board, as there is rarely any warning printed on the can.

 

[whiteoaks7]

Re: \"clever\" gas detector. Advice please

Hi VicS - you've found an error in my write-up so thanks for that. The circuit diagram correctly has the propane/butane version of the sensor LPM2610 - RS538-9910. The Velleman kit was a quick and simple way of providing a comparator - since the sensor is a resistive device you may find if you drive a sounder directly that the thing emits noise even below the setpoint detection threshold. Figaro suggest a comparator.

Cheers, Dave

 

[bluedragon]

Re: \"clever\" gas detector. Advice please

Try it with an open container of diesel near the sensor. My gas detector picks up all sorts of vapours down in the bilge and goes off, not just LPG. It's a bit of a nuisance really.