X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Fri, 03 Feb 2012 13:10:13 -0500 Message-ID: X-Original-Return-Path: Received: from nm1.bullet.mail.sp2.yahoo.com ([98.139.91.71] verified) by logan.com (CommuniGate Pro SMTP 5.4.4) with SMTP id 5381745 for lml@lancaironline.net; Fri, 03 Feb 2012 12:49:44 -0500 Received-SPF: none receiver=logan.com; client-ip=98.139.91.71; envelope-from=chris_zavatson@yahoo.com Received: from [98.139.91.68] by nm1.bullet.mail.sp2.yahoo.com with NNFMP; 03 Feb 2012 17:49:10 -0000 Received: from [98.139.91.34] by tm8.bullet.mail.sp2.yahoo.com with NNFMP; 03 Feb 2012 17:49:10 -0000 Received: from [127.0.0.1] by omp1034.mail.sp2.yahoo.com with NNFMP; 03 Feb 2012 17:49:10 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 483438.86726.bm@omp1034.mail.sp2.yahoo.com Received: (qmail 38413 invoked by uid 60001); 3 Feb 2012 17:49:09 -0000 DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:In-Reply-To:MIME-Version:Content-Type; b=S+gqSbmRnB8kcPMfTluekXUtS1hTHh+NWgnVFAiti+cHyCoBgQ0563NjZjo9N/DMZ3C2nGt70e0wnbynRUqQ/veyTAE45V6tL1jRRmWrUgeOZ6WgrKdsvq9SUtzKQSSG8hLYv8W5tFKMFGCjlW112IgYUzFjRaXZjSOMtt9Fiak=; X-YMail-OSG: vrvipPQVM1lKhMQGPhxjibPq2kdWRp80V5IzprzccKE78ml aa3o9kYE3Bq0vJYkPV33qk7WcKokz6PRPu2cD76FFw5UfW_zeBSRAE5TTUXl OL6lNszo6ya2rFWsyY412vtvfg.PqKR6Lja2vGZygpTUaCOVCXf8AEr7wo6t HePAwCgrHDYKraE6zqE5nwMJy_Im.ONq7RP3l67cdt_RNRn9C3gj_7G8Dhzb uKETBJ3iVeQeLNtie8maqcDmVs9nJCbPcgyWIMTYACjHXR7AxBQWa3iq7u3C 9sMM9P8iZg71CF6IJ6M3H_pJgRp3r17zXCT3KlhY3sxOrFiESt6BhZYYec_E 5BDQLcF0LVxvSnc_Z_7.utGpD5pR0_MWZ.Qvkdu1ueXiAwTSAU4CYRWcgnDo 1Em8_HS78.1psNx9xfhulOVlNDag1h4aJuDToShZYvwd09LC3RROjJRdohcK BFIqihU3t6DbiVv2ZknzFxXOM.nHwIL9Bow47gAOnNtVoO5EbsW2MgYkGwNO 2sj6oQlGuLnHiu_Mtv7iaodUhSJGIqaIB7Hwyxno5Qar4kTYfLTytqxMRFh9 dF9Z2h5m.x2Ds0NFLVkQ9BdQnsWCR5XO8fnOIzKy1RGGek0SeqOlg_6AMP4Z TFIGYzU8fkOqFgFRc8ZCS1pDbhgFgBKLxscrkGJeAicT95U8x7_gbhiaSKbN rkhDDKel9I0xe05QnyyP0aP8wZW38OdUEPdWdYoPObWI0BJql.ZWJ5nbJuXs g1h_5TT2N_h.xl4ChW7oTJc8lff6F_dKGotEKMr70kkKKmC4RaliX14.e9ke 7ljIAsVEnbo.fCF1p.Ytdp7bI1YMLWc0aMNS3BnWodpTX34lkH18egx01Hj5 wqBnPdXT7deXjI0PTJqzkSlWYSEKoD1Q3DaVjG5N01Iln4IWYGK9xuFivFIH jgx1aDdWvd.yj3ZYGH3Y2gHpM1SaTAG9xH6oTt4yELHIB_uQXlGyB.u4f Received: from [12.130.164.194] by web36901.mail.mud.yahoo.com via HTTP; Fri, 03 Feb 2012 09:49:09 PST X-Mailer: YahooMailWebService/0.8.116.331537 References: <71F2EDC3-4167-46D3-86EC-C0BD049DAA77@yahoo.com> X-Original-Message-ID: <1328291349.13087.YahooMailNeo@web36901.mail.mud.yahoo.com> X-Original-Date: Fri, 3 Feb 2012 09:49:09 -0800 (PST) From: Chris Zavatson Reply-To: Chris Zavatson Subject: Re: [LML] 320/360 Hydraulic Pressure Switch X-Original-To: Lancair Mailing List In-Reply-To: <71F2EDC3-4167-46D3-86EC-C0BD049DAA77@yahoo.com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-2114655128-364687383-1328291349=:13087" ---2114655128-364687383-1328291349=:13087 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Bill,=0AThe TRV is selected based on system operating pressures and not pum= p capabilities. =C2=A0It is there to protect your cylinders and lines and a= nything else downstream of the poppet valves=C2=A0in case of excessive=C2= =A0thermal heating.=C2=A0=C2=A0If we ran our systems at higher pressures, w= e would need a different TRV.=0A=C2=A0Pressure switch setting=C2=A0< adjust= able relief valve setting=C2=A0< thermal relief valve setting=0A=0AChris Za= vatson=0AN91CZ=0A360sd=0Awww.N91CZ.net=0A=0AOn Feb 3, 2012, at 5:02 AM, Bil= l Hannahan wrote:=0A=0A>=0A>Chris, thanks for the fe= edback and the work you did.=0A>=C2=A0=0A>I sense a contradiction in this s= tatement;=0A>=C2=A0=0A>[Our pumps come with the lowest of three fixed TRVva= lues.=C2=A0 The set-point is 2,500 psi, thus the statement "approximately 1= 00-140 bar (1500-2000 psi) above the system relief valve pressure" still ho= lds true.]=0A>=C2=A0=0A>I see two interpretations.=0A>=C2=A0=0A>1=E2=80=A6 = The TRV =E2=80=9Csetpoint is 2,500 psi=E2=80=9D, presumably referenced to r= eservoir pressure, which is ambient cabin pressure assuming the reservoir i= s well vented. Thus the TRV will limit the output pressure to 2,500 psig ma= x. In that case the graphs in the brochure do not apply for our pumps above= 2500 psi.=0A>=C2=A0=0A>2=E2=80=A6 The TRV setpoint is=E2=80=9C(1500-2000 p= si) above the system relief valve pressure.=E2=80=9D I interpret =E2=80=9Cs= ystem relief valve pressure=E2=80=9D to be the setpoint of the internal HPR= V or LPRV located upstream of the check valves. These set points are not sp= ecified in the brochure, but the performance graphs indicate that the HPRV = is at least 3,000 psi which would make the TRV setpoint 4,500 - 5,000 psig.= =0A>=C2=A0=0A>Perhaps you are saying the TRV setpoint is 1,500 =E2=80=93 2,= 000 psi above the pressure switch setpoint=E2=80=99s, but I was commenting = on this quote from the brochure which says something else.=0A>=C2=A0=0A>=E2= =80=9CIt is a fixed relief valve with a pressure setting approximately 100-= 140 bar (1500-2000 psi) above the system relief valve pressure.=E2=80=9D=0A= >=0A>If the TRV setpoint is lower than the HPRV and LPRV setpoints I see no= need for the HPRV and LPRV. What is their purpose?=0A>=C2=A0=0A>=0A>I woul= d like to know how much pressure it takes to keep the wheels in the wells d= uring a high speed high G pullup. If the relief valve lifts and the gear co= mes out of the wells, it could literally blow the doors off the airplane. I= f anybody with gauges does a gear test in the next few months, please note = the pressure just before the gear tightens up in the wells and let me know.= Five times that number should be about right.=0A>Regards,=0A>Bill Hannahan= =0A>wfhannahan@yahoo.com=0A>=0A>=0A>From: Chris Zavatson =0A>To: lml@lancaironline.net =0A>Sent: Wednesday, February 1, 2012= 11:20 AM=0A>Subject: [LML] Re: 320/360 Hydraulic Pressure Switch=0A>=0A>Bi= ll,=0A>Our pumps come with the lowest of three fixed TRV values.=C2=A0 The = set-point is 2,500 psi, thus the statement "approximately 100-140 bar (1500= -2000 psi) above the system relief valve pressure" still holds true.=0A>=C2= =A0=0A>re: question three:3=E2=80=A6 Does the momentum of the motor cause t= he pressure to spike well above the pressure set point?=0A>The pressure doe= s shoot beyond the set point=C2=A0due to inertia of the motor and pump.=C2= =A0 As the hoses etc. stretch in the first second or two, the pressure come= s back down a bit.=C2=A0 The stiffer the system is, the greater the pressur= e will shoot beyond the set-point.=C2=A0 On the test bench with a mere 3 fe= et of hose, the overshoot is quite a bit greater that in a fully populated = aircraft.=0A>=0A>=0A>Chris Zavatson=0A>N91CZ=0A>360std=0A>www.N91CZ.net=0A>= =0A>=C2=A0=0A>=0A>=0A>From: Bill Hannahan =0A>To: lml= @lancaironline.net =0A>Sent: Tuesday, January 31, 2012 3:46 PM=0A>Subject: = [LML] 320/360 Hydraulic Pressure Switch=0A>=0A>=0A>=0A>Regarding this quote= on the trv from the Oildyne brocure;=0A>=0A>=E2=80=9CIt is a fixed relief = valve with a pressure=0A>setting approximately 100-140 bar (1500-2000 psi)= =0A>above the system relief valve pressure.=E2=80=9D=0A>=C2=A0=0A>As I read= this, if the pump is rated to produce flow at 3000 psi, the TRV is set for= 4500 =E2=80=93 5000 psi. That seems way too high for our systems.=0A>=C2= =A0=0A>=C2=A0=0A>The third set of pressure switches on my 360 are acting up= . I am thinking about a spring project to upgrade them. I bought two new/ol= d stock pressure switches for about $75 including shipping.=0A>=C2=A0=0A>ht= tp://www.ebay.com/itm/DIRECT-AUTOMATION-PSD25-0P-1450H-PRESSURE-SWITCH-/220= 904940181?_trksid=3Dp3286.m7&_trkparms=3Dalgo%3DLVI%26itu%3DUCI%26otn%3D3%2= 6po%3DLVI%26ps%3D63%26clkid%3D6005931030562248892=0A>=0A>=0A>They are limit= ed to 250 ma load current and a max overload of 2900 psi. My plan is to res= et the TRV=E2=80=99s to the neighborhood of 1200 psi. At that pressure moto= r current is less than 30 amps.=0A>=0A>I found 50 amp PNP Darlington transi= stors to replace the big power relays. They have enough gain to be driven d= irectly from the pressure switch through an appropriate resistor.=0A>=0A>ht= tp://www.ebay.com/itm/MJ11032-Darlington-Power-transistors-NPN-Audio-Amp-x2= -/180663839378?pt=3DLH_DefaultDomain_0&hash=3Ditem2a10676a92=0A>=0A>=0A>I w= ould appreciate some information from those who have installed pressure gau= ges. =0A>=0A>1=E2=80=A6 At what pressure does your up pressure switch close= and open?=0A>=0A>2=E2=80=A6 At what pressure does your down pressure switc= h close and open?=0A>=0A>3=E2=80=A6 Does the momentum of the motor cause th= e pressure to spike well above the pressure setpoint?=0A>=0A>4=E2=80=A6 In = high G pull-ups and/or turbulence, do you see fluctuations in pressure, fro= m what to what?=0A>=0A>Thanks for your feedback.=0A>=0A>=0A>=0A>=0A>Regards= ,=0A>Bill Hannahan=0A>wfhannahan@yahoo.com=0A>=0A>--- On Mon, 1/30/12, Bruc= e wrote:=0A>=0A>=0A>>From: Bruce =0A= >>Subject: [LML] Re: IV-P Hydraulic Pressure Switch=0A>>To: lml@lancaironli= ne.net=0A>>Date: Monday, January 30, 2012, 12:05 PM=0A>>=0A>>=0A>>You might= look at,=0A>>=C2=A0=0A>>http://www.automationdirect.com/adc/Shopping/Catal= og/Sensors_-z-_Encoders/Pressure_Sensors_-a-_Pressure_Gauges/Pressure_Switc= hes/PSD25-0P-5800H=0A>>=C2=A0=0A>>Solid state and adjustable, don=E2=80=99t= forget the matching cable =0A>>=C2=A0=0A>>Bruce=0A>>WWW.Glasair.org =0A>>-= ----Original Message-----=0A>>From: Lancair Mailing List [mailto:lml@lancai= ronline.net] On Behalf Of Craig Berland.=0A>>Sent: Monday, January 30, 2012= 10:53 AM=0A>>To: lml@lancaironline.net=0A>>Subject: [LML] IV-P Hydraulic P= ressure Switch=0A>>=C2=A0=0A>>A few weeks ago when returning home my main l= anding gear failed to extend.=C2=A0 I have determined the pressure switch t= hat controls the hydraulic pump relay has failed. The kit supplied switch h= as a minimum temperature rating of -22 deg F.=C2=A0 Since my switch failed = with about 110 hrs on it, has anybody found a better switch?=0A>>On a perso= nal note: When building N7VG, the only thing my wife wanted was her own per= sonal landing gear lights. She was all over the fact that the mains did not= lock down. The emergency pump worked and all is well.=0A>>Craig Berland=0A= >>IV-P N7VG=0A>>=C2=A0 ---2114655128-364687383-1328291349=:13087 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Bill,
The TRV is selected based on system operating pressures and not pump capabilities= .  It is there to protect your cylinders= and lines and anything else downstream of the poppet valves in case o= f excessive thermal heating.  If we ran our systems at highe= r pressures, we would need a different T= RV.
 Pressure switch setting < adjustab= le relief valve setting < thermal relief valve setting
 
Chris Zavatson
N91CZ
360sd<= /DIV>
 
 
Chris, thanks for the feedback an= d the work you did.
 
I sense a contradiction in this s= tatement;
 
[Our pumps come with the lowest o= f three fixed TRV values.  The set-point is 2,500 ps= i, thus the statement "approximately 100-140 bar (1500-2000 ps= i) above the system relief valve pressure" still = holds true.]
 
I see two interpretations.=
 
1=E2=80=A6 The TRV =E2=80=9Cset= point is 2,500 psi=E2=80=9D, presumably referenced to reservoir pres= sure, which is ambient cabin pressure assuming the reservoir is well vented= . Thus the TRV will limit the out= put pressure to 2,500 psig max. I= n that case the graphs in the brochure do not apply for our pumps above 250= 0 psi.
 
2=E2=80=A6 The TRV setpoint is =E2=80=9C(1500-2000 psi) above the syste= m relief valve pressure.=E2=80=9D I interpret =E2=80=9Csystem relief valve = pressure=E2=80=9D to be the setpoint of the internal HPRV or LPRV located upstream of the check = valves. These set points are not specified in the brochure, but the perform= ance graphs indicate that the HPRV is at least 3,000 psi which would make the TRV setpoint 4,50= 0 - 5,000 psig.
 
Perhaps you are saying the TRV setpoint is 1,500 =E2=80=93 2,000 psi above the pressure switch setpoint=E2=80=99s, but I was comm= enting on this quote from the brochure which says something else.
 
=E2=80=9CIt is a fixed relief val= ve with a pressure setting approximately 100-140 bar (1500-2000 psi) above = the system relief valve pressure.=E2=80=9D
 
If the TRV setpoint is= lower than the HPRV and LPRV setpoints I see no need for the HPRV and LPRV. What is = their purpose?
 
 
I would like to know how much pressure = it takes to keep the wheels in the wells during a high speed high G pullup. If the relief valve lifts and t= he gear comes out of the wells, it could literally blow the doors off the a= irplane. If anybody with gauges = does a gear test in the next few months, please note the pressure just befo= re the gear tightens up in the wells and let me know. Five times that numbe= r should be about right.
Regards,
Bill Hannahan
wfhannahan@yahoo.com

Bill,
Our pumps come with the lowest of three fixed TRV values.  The set-point is 2,500 psi, thus the st= atement "approximately 100-140 bar (1500-2000 psi) above the = system relief valve pressure" still holds true.
 
re: question three:
3=E2=80=A6 Does the momentum of the mot= or cause the pressure to spike well above the pressure set point?
The pressure does shoot beyond the set = point due to inertia of the motor and pump.&n= bsp; As the hoses etc. stretch in the first second or two, the pressure com= es back down a bit.  The stiffer the system is, the greater the pressu= re will shoot beyond the set-point.  On the test bench with a mere 3 f= eet of hose, the overshoot is quite a bit greater that in a fully populated= aircraft.
 

From: Bill Hannahan <wfhannahan@yahoo.com><= BR>To: lml@lancaironline.net
Sent: Tuesday, January 31, 2012 3:46 PM
Subject: [LML] 320/360 Hydraulic Pressure Switch
 
Regarding this quote on the trv from the Oildyne<= /SPAN> brocure;
 
=E2=80=9CIt is a fixed relief valve with a pres= sure
setting approximately 100-140 bar (1500-2000 ps= i)
above the system relief valve pressure.=E2=80= =9D
 
As I read this, if the pump is rated to produce= flow at 3000 psi, the TRV is set for 4= 500 =E2=80=93 5000 psi. That seems way too high for our systems.
 
 
The third set of pressure switches on my 360 ar= e acting up. I am thinking about a spring project to upgrade them. I bought= two new/old stock pressure switches for about $75 including shipping.
 
http://www.ebay= .com/itm/DIRECT-AUTOMATION-PSD25-0P-1450H-PRESSURE-SWITCH-/220904940181?_tr= ksid=3Dp3286.m7&_trkparms=3D= algo%3DLVI%26itu%3DUCI%26otn%3D3%26po%3DLVI%26ps%3D63%26clkid%3= D6005931030562248892
 
 
They are limited to 250 ma load current= and a max overload of 2900 psi. My plan is to reset the TRV=E2=80=99s to the neighborhood of 1200 psi. At that p= ressure motor current is less than 30 amps.
 
I found 50 amp P= NP Darlington transistor= s to replace the big power relays. They have enough gain to be driven direc= tly from the pressure switch through an appropriate resistor.
 
http= ://www.ebay.com/itm/MJ11032-Darlington-Power-transistors-NPN-Audio-Amp-x2-/= 180663839378?pt=3DLH_DefaultDomain_0&hash=3Ditem2a10676a92
 
 
I would appreciate some information fro= m those who have installed pressure gauges.
 
1=E2=80=A6 At what pressure does your u= p pressure switch close and open?
 
2=E2=80=A6 At what pressure does your d= own pressure switch close and open?
 
3=E2=80=A6 Does the momentum of the mot= or cause the pressure to spike well above the pressure setpoint?
 
4=E2=80=A6 In high G pull-ups and/or tu= rbulence, do you see fluctuations in pressure, from what to what?
 
Thanks for your feedback.
 
 


Regards,
Bill Hannahan

=
--- On Mon, 1/30/12, Bruce <BGra= y@glasair.org> wrote:

From: Bruce <BGr= ay@glasair.org>
Subject: [LML] Re: IV-P Hydraulic Pressure Switch=
To: lml@lancaironline.net
= Date: Monday, January 30, 2012, 12:05 PM

You migh= t look at,
 
http://www.automationdirect.com/adc/Shopping/= Catalog/Sensors_-z-_Encoders/Pressure_Sensors_-a-_Pressure_Gauges/Pressure_= Switches/PSD25-0P-5800H
 
Solid st= ate and adjustable, don=E2=80=99t forget the matching cable <= /DIV>
 
---= --Original Message-----
From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of Craig Be= rland.
Sent: Monday, January 30, 2012 10:53 AM
lml@lancaironline.ne= t
Subject: [LML] IV-= P Hydraulic Pressure Switch
 
A few weeks ago when re= turning home my main landing gear failed to extend.  I have determined= the pressure switch that controls the hydraulic pump relay has failed. The= kit supplied switch has a minimum temperature rating of -22 deg F.  S= ince my switch failed with about 110 hrs on it, has anybody found a better = switch?
On a personal note: Whe= n building N7VG, the only thing my wife wanted was her own personal landing= gear lights. She was all over the fact that the mains did not lock down. T= he emergency pump worked and all is well.
Craig Berland
IV-P N7VG=
 
<= /DIV>
---2114655128-364687383-1328291349=:13087--