<html><body><div style="font-family: arial, helvetica, sans-serif; font-size: 12pt; color: #000000"><div>Francesco,</div><div><br data-mce-bogus="1"></div><div>If you have reduced flow at the flow meters, the demand flow must be reduced as well. Please change the BMT Flow Set point (on the MVT PLC gas controls interface) to the set point of your flow meters. This will automatically change the demand flow from the mixing system.<br data-mce-bogus="1"></div><div><br></div><div><br></div><div data-marker="__SIG_PRE__">Marc McMullen<br>Physics Division<br>Detector Support Group<br>7738</div><div><br></div><hr id="zwchr" data-marker="__DIVIDER__"><div data-marker="__HEADERS__"><b>From: </b>"Francesco Bossù" <fbossu@jlab.org><br><b>To: </b>"Marc McMullen" <mcmullen@jlab.org><br><b>Cc: </b>dsg-mvt@jlab.org<br><b>Sent: </b>Wednesday, May 16, 2018 9:35:35 AM<br><b>Subject: </b>Re: [Dsg-mvt] [Dsg-hallbgas] micromega gas mix pressures<br></div><div><br></div><div data-marker="__QUOTED_TEXT__">Hi,<br><br>yes, we reduced the request at the flow-meters in the hall because we<br>disconnected 6 detectors. Is is possible to reduced the set point? Can<br>we do it from some panel in Clascss?<br><br>Francesco<br><br><br>On 16/05/2018 15:32, Marc McMullen wrote:<br>> Hi Francesco,<br>><br>> Your flow setpoint is 9.2 but your flow in/out is only 5.0/4.7 liter<br>> per hour. So something is restricting on your end. So your system is<br>> requesting more than your are taking, this is why pressure is building<br>> in the tank. Is it possible that something is valved off?<br>><br>><br>><br>> Marc McMullen<br>> Physics Division<br>> Detector Support Group<br>> 7738<br>><br>> ------------------------------------------------------------------------<br>> *From: *"Francesco Bossù" <fbossu@jlab.org><br>> *To: *dsg-mvt@jlab.org<br>> *Sent: *Wednesday, May 16, 2018 9:26:36 AM<br>> *Subject: *Re: [Dsg-mvt] [Dsg-hallbgas] micromega gas mix pressures<br>><br>> Hi Marc,<br>><br>> yes, the MVT group needs gas until the end of the week for testing the<br>> BMT.<br>><br>> What is the simplest solution? We need to continue our test as soon as<br>> possible.<br>><br>> Thanks<br>><br>> Francesco<br>><br>><br>> On 16/05/2018 15:19, Marc McMullen wrote:<br>> > Hi Morgan,<br>> ><br>> > Just for clarification, please contact the MVT group and ask them to<br>> > check to see if their settings are appropriate. Our system will<br>> > continue to supply the gas as long as it is requested, so the tank<br>> > pressure will not decrease.<br>> ><br>> > Thanks,<br>> ><br>> ><br>> > Marc McMullen<br>> > Physics Division<br>> > Detector Support Group<br>> > 7738<br>> ><br>> > ------------------------------------------------------------------------<br>> > *From: *"Marc McMullen" <mcmullen@jlab.org><br>> > *To: *"Morgan Cook" <mcookiv@jlab.org><br>> > *Cc: *dsg-hallbgas@jlab.org, dsg-mvt@jlab.org<br>> > *Sent: *Wednesday, May 16, 2018 8:58:56 AM<br>> > *Subject: *Re: [Dsg-hallbgas] micromega gas mix pressures<br>> ><br>> > Hi Morgan,<br>> ><br>> > It looks like there is some issue downstream of the mixing system. The<br>> > signals used to supply gas to the barrel (B_DET_BMT_GAS_WANTGAS) is<br>> > still set to supply the gas. But the pressure in the tank is at 20psi<br>> > which is the interlock set point to flow 0 gas. So that pressure is<br>> > too high. I am not sure if the MVT is trying to flow to the barrel on<br>> > their end or not, but if they need flow some pressure has to be<br>> > relieved. They either have to flow more gas down stream of tank or<br>> > relieve the tank.<br>> ><br>> > The signals for the MVT forward tracker and the FTT are set so they<br>> > will not request gas.<br>> ><br>> ><br>> ><br>> ><br>> ><br>> > Marc McMullen<br>> > Physics Division<br>> > Detector Support Group<br>> > 7738<br>> ><br>> > ------------------------------------------------------------------------<br>> > *From: *"Morgan Cook" <mcookiv@jlab.org><br>> > *To: *dsg-hallbgas@jlab.org<br>> > *Sent: *Wednesday, May 16, 2018 8:22:53 AM<br>> > *Subject: *[Dsg-hallbgas] micromega gas mix pressures<br>> ><br>> > Hi,<br>> ><br>> > Is there any particular reason why the Mix2_Press is twice it's 2 week<br>> > average pressure and the Mix1_Press is running at 1/2 it's 2 week<br>> average?<br>> > _______________________________________________<br>> > Dsg-hallbgas mailing list<br>> > Dsg-hallbgas@jlab.org<br>> > https://mailman.jlab.org/mailman/listinfo/dsg-hallbgas<br>> ><br>> > _______________________________________________<br>> > Dsg-hallbgas mailing list<br>> > Dsg-hallbgas@jlab.org<br>> > https://mailman.jlab.org/mailman/listinfo/dsg-hallbgas<br>> ><br>> ><br>> > _______________________________________________<br>> > Dsg-mvt mailing list<br>> > Dsg-mvt@jlab.org<br>> > https://mailman.jlab.org/mailman/listinfo/dsg-mvt<br>><br>> _______________________________________________<br>> Dsg-mvt mailing list<br>> Dsg-mvt@jlab.org<br>> https://mailman.jlab.org/mailman/listinfo/dsg-mvt<br></div></div></body></html>