<html><head></head><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div id="yui_3_16_0_ym19_1_1478077967724_4220"><span id="yui_3_16_0_ym19_1_1478077967724_4219">I just experimented with the flow from the high pressure port</span></div><div id="yui_3_16_0_ym19_1_1478077967724_4182" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4218">on my 1st stage regulator. That's the one your pressure gauge runs off.</span></div><div id="yui_3_16_0_ym19_1_1478077967724_4181" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4217">Even though the hole is literally a pin prick, I was getting at least</span></div><div id="yui_3_16_0_ym19_1_1478077967724_4162" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4161">2 liters a second flow out of it. </span></div><div id="yui_3_16_0_ym19_1_1478077967724_4160" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4159">I am building a similar sized sub to Cliff's R300 & a leak like that,</span></div><div id="yui_3_16_0_ym19_1_1478077967724_4164" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4163">apart from increasing the pressure massively, would be hazardous</span></div><div id="yui_3_16_0_ym19_1_1478077967724_4292" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4291">if it was O2. In 4 minutes I could have 70% O2 based on an air</span></div><div id="yui_3_16_0_ym19_1_1478077967724_4294" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4300">volume in the sub of 250 liters.</span></div><div id="yui_3_16_0_ym19_1_1478077967724_4317" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4334">I think I'll go for a pressure gauge outside my view port or try potting</span></div><div id="yui_3_16_0_ym19_1_1478077967724_4346" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4345">a digital pressure gauge & just send the wires through a penetrator.</span></div><div id="yui_3_16_0_ym19_1_1478077967724_4353" dir="ltr"><span id="yui_3_16_0_ym19_1_1478077967724_4360">Alan</span></div><div class="qtdSeparateBR" id="yui_3_16_0_ym19_1_1478077967724_4078"><br><br></div><div class="yahoo_quoted" id="yui_3_16_0_ym19_1_1478077967724_4158" style="display: block;"> <div id="yui_3_16_0_ym19_1_1478077967724_4157" style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div id="yui_3_16_0_ym19_1_1478077967724_4156" style="font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px;"> <div id="yui_3_16_0_ym19_1_1478077967724_4215" dir="ltr"> <font id="yui_3_16_0_ym19_1_1478077967724_4214" face="Arial" size="2"> <hr size="1" id="yui_3_16_0_ym19_1_1478077967724_4216"> <b><span style="font-weight: bold;">From:</span></b> Alan via Personal_Submersibles <personal_submersibles@psubs.org><br> <b><span style="font-weight: bold;">To:</span></b> Personal Submersibles General Discussion <personal_submersibles@psubs.org> <br> <b><span style="font-weight: bold;">Sent:</span></b> Wednesday, November 2, 2016 12:41 AM<br> <b><span style="font-weight: bold;">Subject:</span></b> Re: [PSUBS-MAILIST] Electronic contents gauge<br> </font> </div> <div class="y_msg_container" id="yui_3_16_0_ym19_1_1478077967724_4155"><br><div id="yiv0636321897"><div id="yui_3_16_0_ym19_1_1478077967724_4212"><div id="yui_3_16_0_ym19_1_1478077967724_4213">Thanks for the advice Steve.</div><div id="yui_3_16_0_ym19_1_1478077967724_4211">I haven't looked in to the electronic oxygen add system too deeply.</div><div>Bound to have some questions later on.</div><div id="yui_3_16_0_ym19_1_1478077967724_4375">Cheers Alan</div><div id="yui_3_16_0_ym19_1_1478077967724_4376"><br clear="none">Sent from my iPad</div><div class="yiv0636321897yqt3305599012" id="yiv0636321897yqt51556"><div id="yui_3_16_0_ym19_1_1478077967724_4377"><br clear="none">On 1/11/2016, at 9:39 pm, Stephen Fordyce via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org" target="_blank" rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<br clear="none"><br clear="none"></div><blockquote id="yui_3_16_0_ym19_1_1478077967724_4381" type="cite"><div id="yui_3_16_0_ym19_1_1478077967724_4380"><div id="yui_3_16_0_ym19_1_1478077967724_4379" dir="ltr"><div id="yui_3_16_0_ym19_1_1478077967724_4378">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.</div><div id="yui_3_16_0_ym19_1_1478077967724_4382"><br clear="none"></div><div id="yui_3_16_0_ym19_1_1478077967724_4383">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!</div><div><br clear="none"></div><div>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).</div><div id="yui_3_16_0_ym19_1_1478077967724_4384"><br clear="none"></div><div id="yui_3_16_0_ym19_1_1478077967724_4385">Cheers,</div><div id="yui_3_16_0_ym19_1_1478077967724_4386">Steve</div><div><br clear="none"></div><div id="yui_3_16_0_ym19_1_1478077967724_4387">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.</div><div><br clear="none"></div><div><br clear="none"></div></div><div class="yiv0636321897gmail_extra" id="yui_3_16_0_ym19_1_1478077967724_4393"><br clear="none"><div class="yiv0636321897gmail_quote" id="yui_3_16_0_ym19_1_1478077967724_4392">On Tue, Nov 1, 2016 at 2:19 PM, Alan James via Personal_Submersibles <span dir="ltr"><<a href="mailto:personal_submersibles@psubs.org" target="_blank" rel="nofollow" shape="rect" ymailto="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>></span> wrote:<br clear="none"><blockquote class="yiv0636321897gmail_quote" id="yui_3_16_0_ym19_1_1478077967724_4391" style="margin: 0px 0px 0px 0.8ex; padding-left: 1ex; border-left-color: rgb(204, 204, 204); border-left-width: 1px; border-left-style: solid;"><div id="yui_3_16_0_ym19_1_1478077967724_4390"><div id="yui_3_16_0_ym19_1_1478077967724_4389" style="color: rgb(0, 0, 0); font-family: HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif; font-size: 16px; background-color: rgb(255, 255, 255);"><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3134"><br clear="none">Steve,</div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3183" dir="ltr">sending this again as I didn't receive it...</div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3186"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3187">Steve,</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3188"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3189">I am wanting to build an O2 system like James Cameron had.</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3190"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3191">An O2 valve that flows continuously with a top up from a solenoid</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3192" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3193">valve which triggered by a plc that is receiving signals from 3 x O2 sensors. </span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3194" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3195">Mainly because I want to keep everything as small as possible.</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3196" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3197"> With your O2 unit it looks like you could have it doing similar;</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3198" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3199">turn on a solenoid to top up the O2 beyond what is flowing in from</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3200" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3201">a pre-set valve. A bellows add system that replaces the bellows with</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3202" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3203">your "Oxygen Watchdog"</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3204" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3205">Know what you mean about UK freight charges, have cancelled items</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3206" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3207">because of ridiculous freight charges. Thanks for the offer of buying</span></div><div id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3208" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3209">through your firm.</span></div><div id="yiv0636321897m_-1904202565053152574yiv7750647722yui_3_16_0_ym19_1_1477958744792_5053" dir="ltr"><span id="yiv0636321897m_-1904202565053152574yui_3_16_0_ym19_1_1477970226444_3211">Cheers Alan</span></div></div></div><br clear="none">______________________________ _________________<br clear="none">
Personal_Submersibles mailing list<br clear="none">
<a id="yui_3_16_0_ym19_1_1478077967724_4394" href="mailto:Personal_Submersibles@psubs.org" target="_blank" rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs. org</a><br clear="none">
<a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank" rel="nofollow" shape="rect">http://www.psubs.org/mailman/ listinfo.cgi/personal_ submersibles</a><br clear="none">
<br clear="none"></blockquote></div><br clear="none"></div>
</div></blockquote></div><blockquote id="yui_3_16_0_ym19_1_1478077967724_4398" type="cite"><div id="yui_3_16_0_ym19_1_1478077967724_4397"><span>_______________________________________________</span><br clear="none"><span>Personal_Submersibles mailing list</span><br clear="none"><span id="yui_3_16_0_ym19_1_1478077967724_4396"><a id="yui_3_16_0_ym19_1_1478077967724_4395" href="mailto:Personal_Submersibles@psubs.org" target="_blank" rel="nofollow" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a></span><br clear="none"><span><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank" rel="nofollow" shape="rect">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a></span><br clear="none"></div></blockquote></div></div><br><div class="yqt3305599012" id="yqt31552">_______________________________________________<br clear="none">Personal_Submersibles mailing list<br clear="none"><a href="mailto:Personal_Submersibles@psubs.org" shape="rect" ymailto="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br clear="none"><a id="yui_3_16_0_ym19_1_1478077967724_4399" href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" target="_blank" shape="rect">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br clear="none"></div><br><br></div> </div> </div> </div></div></body></html>