<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">Hi guys, thanks for the input. I will take it as a compliment that you think I can manage these electronic solutions. <div>I will opt for a more simple system. I ordered a compressor pressure switch. I will modify the low pressure setting. The switch will activate a small solenoid to fill the chamber to 175 psi. The chamber will have a bleed valve that is constantly bleeding very slowly. Once the pressure drops to near zero, the switch will tell the solenoid to fill the chamber again. We can time the cycle, and walk away for a month. </div><div>Hank<br><br><div dir="ltr">Sent from my iPhone</div><div dir="ltr"><br><blockquote type="cite">On Nov 13, 2022, at 8:33 PM, Cliff Redus via Personal_Submersibles <personal_submersibles@psubs.org> wrote:<br><br></blockquote></div><blockquote type="cite"><div dir="ltr"><!--[if gte mso 9]><xml><o:OfficeDocumentSettings><o:AllowPNG/><o:PixelsPerInch>96</o:PixelsPerInch></o:OfficeDocumentSettings></xml><![endif]--><div class="ydpeba02843yahoo-style-wrap" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><div style="font-family: times new roman, new york, times, serif; font-size: 16px;"></div>
<div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;">Hank,</div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><br></div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;">I would use a direct acting cartridge style proportional pressures reducing valve, something like a Hydraforce <span><span style="color: rgb(102, 102, 102); font-family: Montserrat; font-size: 16px;">EHPR08-33X </span></span><a href="https://www.hydraforce.com/products/valves/electro-proportional-controls/ehpr08-33/" rel="nofollow" target="_blank" class="enhancr_card_8469163983">Hydraforce | Pressure Rising with Current - EHPR08-33</a>. These are installed in a small aluminum manifold in which you connect hydraulic tubing with Swagelok fittings. These valves let you specify a control signal, usually 4-20mA. They then can be used to automatically hold the pressure and any level between zero and the maximum your pressure supply can make. You then use a small inexpensive PLC like the Automation Direct Click PLC <a href="https://www.automationdirect.com/adc/overview/catalog/programmable_controllers/click_plcs_(stackable_micro_brick)" rel="nofollow" target="_blank" class="enhancr_card_8717910036">CLICK (Stackable Micro Brick PLC) | AutomationDirect</a> along with pressure transducer and an inexpensive small touch screen display. Again, you can get these from Automationdirect. You would also need to install in the PLC an analog current output that will would be connected to the proportional pressure regulator. You then program the PLC with your laptop with some simple ladder logic that sends the control current to the proportional pressure regulator to step through the pressures you want the test chamber to see over time. Most of these small PLC's have data logging capability so you can log test chamber pressure as a function of time. If you also installed a contactor on the power to the pressure supply, the PLC could be programed to shut down the system if the viewport failed based on the measured test chamber pressure dropping to zero. </div><div><br></div><div id="ydp42158c62enhancr_card_8717910036" class="ydp42158c62yahoo-link-enhancr-card ydp42158c62yahoo-link-enhancr-not-allow-cover ydp42158c62ymail-preserve-class ydp42158c62ymail-preserve-style" style="max-width:400px;font-family:YahooSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif" data-url="https://www.automationdirect.com/adc/overview/catalog/programmable_controllers/click_plcs_(stackable_micro_brick)" data-type="YENHANCER" data-size="MEDIUM" contenteditable="false"><a href="https://www.automationdirect.com/adc/overview/catalog/programmable_controllers/click_plcs_(stackable_micro_brick)" style="text-decoration:none !important;color:#000 !important" class="ydp42158c62yahoo-enhancr-cardlink" rel="nofollow" target="_blank"><table border="0" class="ydp42158c62card-wrapper ydp42158c62yahoo-ignore-table" cellpadding="0" cellspacing="0" style="max-width:400px"><tbody><tr><td width="400"><table border="0" class="ydp42158c62card ydp42158c62yahoo-ignore-table" cellpadding="0" cellspacing="0" width="100%" style="max-width:400px;border-width:1px;border-style:solid;border-color:rgb(224, 228, 233);border-radius:2px"><tbody><tr><td><table border="0" class="ydp42158c62card-info ydp42158c62yahoo-ignore-table" cellpadding="0" cellspacing="0" style="background:#fff;position:relative;z-index:2;width:100%;max-width:400px;border-radius:0 0 2px 2px;border-top:1px solid rgb(224, 228, 233)"><tbody><tr><td style="background-color:#ffffff;padding:16px 0 16px 12px;vertical-align:top;border-radius:0 0 0 2px"></td><td style="vertical-align:middle;padding:12px 24px 16px 12px;width:99%;font-family:YahooSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif;border-radius:0 0 2px 0"><h2 class="ydp42158c62card-title" style="font-size: 14px; line-height: 19px; margin: 0px 0px 6px; font-family: YahooSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif; color: rgb(29, 34, 40); max-width: 314px;">CLICK (Stackable Micro Brick PLC) | AutomationDirect</h2><p class="ydp42158c62card-description" style="font-size: 12px; line-height: 16px; margin: 0px; color: rgb(151, 158, 168);">Save on CLICK Series Programmable Logic Controllers at AutomationDirect, your source for Click PLCs at low price...</p></td></tr></tbody></table></td></tr></tbody></table></td></tr></tbody></table></a></div><div><br></div><div><br></div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><br></div><div dir="ltr" data-setdir="false" style="">These proportional pressures reducing valve could also be run with a microprocessor like Jon uses and setup in a similar way.</div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><br></div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;">Best </div><div style="font-family: times new roman, new york, times, serif; font-size: 16px;"><br></div><div id="ydp70c3b12enhancr_card_8469163983" class="ydp70c3b12yahoo-link-enhancr-card ydp70c3b12yahoo-link-enhancr-not-allow-cover ydp70c3b12ymail-preserve-class ydp70c3b12ymail-preserve-style" style="font-family: YahooSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif; font-size: 16px; max-width: 400px; position: relative;" data-url="https://www.hydraforce.com/products/valves/electro-proportional-controls/ehpr08-33/" data-type="YENHANCER" data-size="MEDIUM" contenteditable="false"><a href="https://www.hydraforce.com/products/valves/electro-proportional-controls/ehpr08-33/" style="text-decoration:none !important;color:#000 !important" class="ydp70c3b12yahoo-enhancr-cardlink" rel="nofollow" target="_blank"><table border="0" class="ydp70c3b12card-wrapper ydp70c3b12yahoo-ignore-table" cellpadding="0" cellspacing="0" style="max-width:400px"><tbody><tr><td width="400"><table border="0" class="ydp70c3b12card ydp70c3b12yahoo-ignore-table" cellpadding="0" cellspacing="0" width="100%" style="max-width:400px;border-width:1px;border-style:solid;border-color:rgb(224, 228, 233);border-radius:2px"><tbody><tr><td><table border="0" class="ydp70c3b12card-info ydp70c3b12yahoo-ignore-table" cellpadding="0" cellspacing="0" style="background:#fff;position:relative;z-index:2;width:100%;max-width:400px;border-radius:0 0 2px 2px;border-top:1px solid rgb(224, 228, 233)"><tbody><tr><td style="background-color:#ffffff;padding:16px 0 16px 12px;vertical-align:top;border-radius:0 0 0 2px"></td><td style="vertical-align:middle;padding:12px 24px 16px 12px;width:99%;font-family:YahooSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif;border-radius:0 0 2px 0"><h2 class="ydp70c3b12card-title" style="font-size: 14px; line-height: 19px; margin: 0px 0px 6px; font-family: YahooSans, Helvetica Neue, Segoe UI, Helvetica, Arial, sans-serif; color: rgb(29, 34, 40); max-width: 314px;">Hydraforce | Pressure Rising with Current - EHPR08-33</h2><p class="ydp70c3b12card-description" style="font-size: 12px; line-height: 16px; margin: 0px; color: rgb(151, 158, 168);">PROPORTIONAL PRESSURE REDUCING / RELIEVING CARTRIDGE VALVE</p></td></tr></tbody></table></td></tr></tbody></table></td></tr></tbody></table></a><div class="loadingSpinnerContainer" style="position: absolute; top: 0px; width: 100%; height: 100%; display: flex; align-items: center; justify-content: center; background-color: rgba(255, 255, 255, 0.3);"><div class="D_F F_n gl_C ab_C H_6MGW o_h"><div class="W_6MGW H_6MGW D_X ah_1PEzoz" data-test-id="loading_indicator"><svg class="W_6MGW H_6MGW ah_Zq6hUs" viewBox="0 0 24 24" width="24" height="24"><path class="cdPFi_n cZ13pKbK_Z29WjXl cZ1XO2Ji_dRA c2abBOT_EY cZ1vNhDV_rd cZV8aCd_pI ah_14s73" d="M12,22C6.477,22,2,17.523,2,12S6.477,2,12,2"></path><path class="cdPFi_n cZ13pKbK_Z29WjXl cZ1XO2Ji_dRA c2abBOT_EY cZ1vNhDV_rd cZV8aCd_pI ah_14s73" d="M12,2c5.523,0,10,4.477,10,10s-4.477,10-10,10"></path></svg></div></div></div></div><div style="font-family: times new roman, new york, times, serif; font-size: 16px;">. </div><div style="font-family: times new roman, new york, times, serif; font-size: 16px;"><br></div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><br></div><div dir="ltr" data-setdir="false" style="font-family: times new roman, new york, times, serif; font-size: 16px;"><br></div><div style="font-family: times new roman, new york, times, serif; font-size: 16px;"><br></div>
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On Sunday, November 13, 2022 at 09:45:39 AM CST, hank pronk via Personal_Submersibles <personal_submersibles@psubs.org> wrote:
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<div><div dir="ltr">Hi submarine friends. I just completed a pressure test to failure on our Cast Epoxy port. The port was 1 inch by 8 inches OD. An acrylic port this size is rated to fail at 2,100 feet sea water. My Epoxy port failed at 1,225 psi or 2,744 feet fresh water. <br></div><div dir="ltr"> Any ideas on how to make a hydraulic apparatus to cycle the port from zero to operating depth in my chamber? <br></div><div dir="ltr">Hank<br></div><div dir="ltr">Sent from my iPhone<br></div><div dir="ltr"><br></div><div dir="ltr">_______________________________________________<br></div><div dir="ltr">Personal_Submersibles mailing list<br></div><div dir="ltr"><a href="mailto:Personal_Submersibles@psubs.org" rel="nofollow" target="_blank">Personal_Submersibles@psubs.org</a><br></div><div dir="ltr"><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles" rel="nofollow" target="_blank">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><br></div></div>
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