[PSUBS-MAILIST] Electronic contents gauge

[Stephen Fordyce via Personal_Submersibles]

Thanks Alan - I should probably point out that my Watchdogs are rather
literally named - ie. they can sense something is wrong and do
something simple about it, but are limited in how complex the reaction can
be.  It can only handle one O2 input, and the control is limited
by controller settings - it's an off-the-shelf item and not fully
programmable like a PLC.  Good for an independent backup or alarm.  As a
primary system it could be made to work but would require a thoughtful
setup.

Eventually I do plan to make a rebreather controller (for the rebreather
I'm designing) which would be perfect (many O2 cell inputs and a solenoid
or two output), but that's a while away!

A key thing to consider in automatic oxygen adding is placement of
sensors, natural mixing of the air and sufficient time delay in the control
system to get meaningful feedback before the next oxygen
injection (Ie. rebreather controllers squirt a little bit of oxygen in,
wait a few seconds for it to mix, and then measure, and squirt in more
accordingly).

Cheers,
Steve

PS: I also have some M12 plated brass Blue Globe cable glands if you find
yourself short a couple - very hard to get down here.



On Tue, Nov 1, 2016 at 2:19 PM, Alan James via Personal_Submersibles <
personal_submersibles at psubs.org> wrote:

>
> Steve,
> sending this again as I didn't receive it...
> Steve,
> I am wanting to build an O2 system like James Cameron had.
> An O2 valve that flows continuously with a top up from a solenoid
> valve which  triggered by a plc that is receiving signals from 3 x O2
> sensors.
> Mainly because I want to keep everything as small as possible.
>    With your O2 unit it looks like you could have it doing similar;
> turn on a solenoid to top up the O2 beyond what is flowing in from
> a pre-set valve. A bellows add system that replaces the bellows with
> your "Oxygen Watchdog"
> Know what you mean about UK freight charges, have cancelled items
> because of ridiculous freight charges. Thanks for the offer of buying
> through your firm.
> Cheers Alan
>
> _______________________________________________
> Personal_Submersibles mailing list
> Personal_Submersibles at psubs.org
> http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.whoweb.com/pipermail/personal_submersibles/attachments/20161101/ab2ba621/attachment.html>