--- title: Tri-Sen Blog description: Topics related to turbomachinery controls --- [![26TRIS065-Tri-Sen 50 years logo-R2](https://blog.tri-sen.com/hs-fs/hubfs/Assets/26TRIS065-Tri-Sen%2050%20years%20logo-R2.png?width=1476&height=573&name=26TRIS065-Tri-Sen%2050%20years%20logo-R2.png "26TRIS065-Tri-Sen 50 years logo-R2")](https://tri-sen.com/) # Tri-Sen Blog [![](https://blog.tri-sen.com/hs-fs/hubfs/red%20alligator%20with%20text.png?width=690&name=red%20alligator%20with%20text.png) ](https://blog.tri-sen.com/proof_test_intervals) ## [Proof Test Intervals (PTI) as Proxy for Reliability](https://blog.tri-sen.com/proof_test_intervals) Posted by [Harry L. Cheddie, P.Eng.,CRE, CQE, CFSE](https://blog.tri-sen.com/author/harry-cheddie) on Nov 4, 2025 2:56:55 PM - [Tweet](https://twitter.com/share) It's been a minute, so to get back in the swing of things, we've asked  guest blogger, [Mr. Harry Cheddie, ](https://blog.tri-sen.com/author/harry-cheddie)P.Eng. CRE, CQE, CFSE; an industry-recognized expert in industrial safety, to comment on the [...] [Read More](https://blog.tri-sen.com/proof_test_intervals) 0 Comments [Click here to read/write comments](https://blog.tri-sen.com/proof_test_intervals#comments-listing) [ turbine safety ](https://blog.tri-sen.com/topic/turbine-safety) , [ safety systems ](https://blog.tri-sen.com/topic/safety-systems) , [ PFD average ](https://blog.tri-sen.com/topic/pfd-average) , [ proof test interval ](https://blog.tri-sen.com/topic/proof-test-interval) , [ PTI ](https://blog.tri-sen.com/topic/pti) , [ TSODS ](https://blog.tri-sen.com/topic/tsods) , [ overspeed detection ](https://blog.tri-sen.com/topic/overspeed-detection) [![](https://blog.tri-sen.com/hs-fs/hubfs/blog/trip%20block%20architecture/TetraSentry%20for%20blog%20r2.png?width=690&name=TetraSentry%20for%20blog%20r2.png) ](https://blog.tri-sen.com/hydraulic_trip_architecture) ## [Hydraulic trip Interface failure probabilities and spurious trip rates](https://blog.tri-sen.com/hydraulic_trip_architecture) Posted by [Harry L. Cheddie, P.Eng.,CRE, CQE, CFSE](https://blog.tri-sen.com/author/harry-cheddie) on Sep 1, 2020 9:30:00 AM - [Tweet](https://twitter.com/share) We're going to change it up a little this post with a guest blogger, [Mr. Harry Cheddie, ](https://blog.tri-sen.com/author/harry-cheddie)P.Eng. CRE, CQE, CFSE; an industry-recognized expert in industrial safety. [Read More](https://blog.tri-sen.com/hydraulic_trip_architecture) 1 Comment [Click here to read/write comments](https://blog.tri-sen.com/hydraulic_trip_architecture#comments-listing) [ turbine safety ](https://blog.tri-sen.com/topic/turbine-safety) , [ hydraulic trip ](https://blog.tri-sen.com/topic/hydraulic-trip) , [ MTTF ](https://blog.tri-sen.com/topic/mttf) , [ trip block ](https://blog.tri-sen.com/topic/trip-block) , [ safety systems ](https://blog.tri-sen.com/topic/safety-systems) , [ PFD average ](https://blog.tri-sen.com/topic/pfd-average) , [ API612 ](https://blog.tri-sen.com/topic/api612) [![](https://blog.tri-sen.com/hs-fs/hubfs/Assets/Triconex_LP/hero-ebara-on-test.jpg?width=690&name=hero-ebara-on-test.jpg) ](https://blog.tri-sen.com/pid_tmc_structures) ## [Turbomachinery PID Control - Structures](https://blog.tri-sen.com/pid_tmc_structures) Posted by [Tom Bailey](https://blog.tri-sen.com/author/tom-bailey) on Jun 23, 2020 7:00:00 AM - [Tweet](https://twitter.com/share) Has it been +two weeks already?  In our last post - [TMC PID basics](https://blog.tri-sen.com/pid_tmc_basics) - we reviewed some basic controls vocabulary associated with "PID control," and then summarized the PID forms (Parallel, Interactive, [...] [Read More](https://blog.tri-sen.com/pid_tmc_structures) 0 Comments [Click here to read/write comments](https://blog.tri-sen.com/pid_tmc_structures#comments-listing) [ PID control ](https://blog.tri-sen.com/topic/pid-control) , [ PID ](https://blog.tri-sen.com/topic/pid) , [ TMC ](https://blog.tri-sen.com/topic/tmc) , [ turbomachinery controls ](https://blog.tri-sen.com/topic/turbomachinery-controls) , [ process control ](https://blog.tri-sen.com/topic/process-control) [![](https://blog.tri-sen.com/hs-fs/hubfs/Old%20products/TS310%20Past%20Products%20hero%20r1.0.png?width=690&name=TS310%20Past%20Products%20hero%20r1.0.png) ](https://blog.tri-sen.com/pid_tmc_basics) ## [Turbomachinery PID Control - the basics](https://blog.tri-sen.com/pid_tmc_basics) Posted by [Tom Bailey](https://blog.tri-sen.com/author/tom-bailey) on Apr 27, 2020 8:59:40 AM - [Tweet](https://twitter.com/share) It's not an overstatement to say that there has been "a lot" of literature written about industrial process control and the venerable PID control algorithm. However, if there's been a lot written [...] [Read More](https://blog.tri-sen.com/pid_tmc_basics) 0 Comments [Click here to read/write comments](https://blog.tri-sen.com/pid_tmc_basics#comments-listing) [ PID control ](https://blog.tri-sen.com/topic/pid-control) , [ PID ](https://blog.tri-sen.com/topic/pid) , [ TMC ](https://blog.tri-sen.com/topic/tmc) , [ turbomachinery controls ](https://blog.tri-sen.com/topic/turbomachinery-controls) , [ process control ](https://blog.tri-sen.com/topic/process-control) ## [Surge Detection - Eleven Frequently Asked Questions](https://blog.tri-sen.com/surgedetection_faqs) Posted by [Tom Bailey](https://blog.tri-sen.com/author/tom-bailey) on Mar 19, 2020 7:00:00 AM - [Tweet](https://twitter.com/share) We've been getting a lot of surge detection questions lately - what follows are the eleven most frequent, surge-detection-related questions we've been asked. [Read More](https://blog.tri-sen.com/surgedetection_faqs) 8 Comments [Click here to read/write comments](https://blog.tri-sen.com/surgedetection_faqs#comments-listing) [ compressor control ](https://blog.tri-sen.com/topic/compressor-control) , [ surge ](https://blog.tri-sen.com/topic/surge) , [ process protection ](https://blog.tri-sen.com/topic/process-protection) , [ surge detection ](https://blog.tri-sen.com/topic/surge-detection) , [ API670 ](https://blog.tri-sen.com/topic/api670) ## [Refrigeration Systems - Quench Control (Part 2)](https://blog.tri-sen.com/quench-control) Posted by [Jim Jacoby](https://blog.tri-sen.com/author/jim-jacoby) on Feb 12, 2020 8:50:57 AM - [Tweet](https://twitter.com/share) In our last post, [Refrigeration Systems - Quench Control (Part 1)](https://blog.tri-sen.com/refrigeration-systems), we discussed the industrial refrigeration process, and basic recycle temperature control. In what follows, we will discuss the [...] [Read More](https://blog.tri-sen.com/quench-control) 0 Comments [Click here to read/write comments](https://blog.tri-sen.com/quench-control#comments-listing) [ "Jim Jacoby ](https://blog.tri-sen.com/topic/jim-jacoby) , [ compressor control ](https://blog.tri-sen.com/topic/compressor-control) , [ surge ](https://blog.tri-sen.com/topic/surge) , [ recycle ](https://blog.tri-sen.com/topic/recycle) , [ quench ](https://blog.tri-sen.com/topic/quench) , [ refrigeration ](https://blog.tri-sen.com/topic/refrigeration) , [ temperature control ](https://blog.tri-sen.com/topic/temperature-control) ## [Refrigeration Systems - Quench Control (Part 1)](https://blog.tri-sen.com/refrigeration-systems) Posted by [Jim Jacoby](https://blog.tri-sen.com/author/jim-jacoby) on Jan 20, 2020 10:23:42 AM - [Tweet](https://twitter.com/share) This will be the first of two posts discussing:  # Quench Control in hydrocarbon processing refrigeration systems. In the hydrocarbon processing industry, refrigeration systems are widely used to [...] [Read More](https://blog.tri-sen.com/refrigeration-systems) 0 Comments [Click here to read/write comments](https://blog.tri-sen.com/refrigeration-systems#comments-listing) [ "Jim Jacoby ](https://blog.tri-sen.com/topic/jim-jacoby) , [ compressor control ](https://blog.tri-sen.com/topic/compressor-control) , [ surge ](https://blog.tri-sen.com/topic/surge) , [ recycle ](https://blog.tri-sen.com/topic/recycle) , [ quench ](https://blog.tri-sen.com/topic/quench) , [ refrigeration ](https://blog.tri-sen.com/topic/refrigeration) ## [Deriving the Universal Surge Curve](https://blog.tri-sen.com/deriving-the-universal-surge-curve) Posted by [Jim Jacoby](https://blog.tri-sen.com/author/jim-jacoby) on Jan 6, 2020 11:37:39 AM - [Tweet](https://twitter.com/share) In this post we will describe how we can convert a compressor manufacturer's compressor performance map to a surge line we can use to determine where, in relation to that surge line, a compressor is [...] [Read More](https://blog.tri-sen.com/deriving-the-universal-surge-curve) 1 Comment [Click here to read/write comments](https://blog.tri-sen.com/deriving-the-universal-surge-curve#comments-listing) [ compressor control ](https://blog.tri-sen.com/topic/compressor-control) , [ surge ](https://blog.tri-sen.com/topic/surge) , [ process protection ](https://blog.tri-sen.com/topic/process-protection) , [ recycle ](https://blog.tri-sen.com/topic/recycle) , [ compressor efficiency ](https://blog.tri-sen.com/topic/compressor-efficiency) , [ polytropic ](https://blog.tri-sen.com/topic/polytropic) , [ surge curve ](https://blog.tri-sen.com/topic/surge-curve) ## [Recycle Valve Sizing for Refrigeration Compressors](https://blog.tri-sen.com/compressor-recycle_valve_sizing_refrigeration) Posted by [Jim Jacoby](https://blog.tri-sen.com/author/jim-jacoby) on Nov 27, 2019 9:49:40 AM - [Tweet](https://twitter.com/share) Proper selection of the recycle valves for a refrigeration compressor can be significantly more complicated than the selection valves for most other anti-surge applications. Refrigeration Compressors [...] [Read More](https://blog.tri-sen.com/compressor-recycle_valve_sizing_refrigeration) 1 Comment [Click here to read/write comments](https://blog.tri-sen.com/compressor-recycle_valve_sizing_refrigeration#comments-listing) [ compressor control ](https://blog.tri-sen.com/topic/compressor-control) , [ surge ](https://blog.tri-sen.com/topic/surge) , [ recycle ](https://blog.tri-sen.com/topic/recycle) , [ quench ](https://blog.tri-sen.com/topic/quench) , [ refrigeration ](https://blog.tri-sen.com/topic/refrigeration) ## [Compressor Control Surge Margin](https://blog.tri-sen.com/compressor-control-surge-margin) Posted by [Jim Jacoby](https://blog.tri-sen.com/author/jim-jacoby) on Oct 28, 2019 4:31:23 PM - [Tweet](https://twitter.com/share) With the proliferation of dedicated digital anti-surge control systems over the last 20 [Read More](https://blog.tri-sen.com/compressor-control-surge-margin) 1 Comment [Click here to read/write comments](https://blog.tri-sen.com/compressor-control-surge-margin#comments-listing) [ compressor control ](https://blog.tri-sen.com/topic/compressor-control) , [ surge ](https://blog.tri-sen.com/topic/surge) , [ surge margin ](https://blog.tri-sen.com/topic/surge-margin) [All posts](https://blog.tri-sen.com/all) [Next](https://blog.tri-sen.com/page/2) ## The Tri-Sen Blog... About once every two weeks we'll discuss a turbomachinery controls topic that; we were either asked about recently, or a topic that we think you might be interested in learning more about.  Topics that are included or that will be: - Compressor Controls - Turbine Controls - Turbine Safety - Relevant API directives - General Industry Happenings ### Subscribe Here! ### Recent Posts ### Posts by Tag - [compressor control (10)](https://blog.tri-sen.com/tag/compressor-control) - [surge (9)](https://blog.tri-sen.com/tag/surge) - [recycle (4)](https://blog.tri-sen.com/tag/recycle) - [process protection (3)](https://blog.tri-sen.com/tag/process-protection) - [quench (3)](https://blog.tri-sen.com/tag/quench) - [refrigeration (3)](https://blog.tri-sen.com/tag/refrigeration) - ["Jim Jacoby (2)](https://blog.tri-sen.com/tag/jim-jacoby) - [PFD average (2)](https://blog.tri-sen.com/tag/pfd-average) - [PID (2)](https://blog.tri-sen.com/tag/pid) - [PID control (2)](https://blog.tri-sen.com/tag/pid-control) - [TMC (2)](https://blog.tri-sen.com/tag/tmc) - [process control (2)](https://blog.tri-sen.com/tag/process-control) - [safety systems (2)](https://blog.tri-sen.com/tag/safety-systems) - [turbine safety (2)](https://blog.tri-sen.com/tag/turbine-safety) - [turbomachinery controls (2)](https://blog.tri-sen.com/tag/turbomachinery-controls) - [API612 (1)](https://blog.tri-sen.com/tag/api612) - [API670 (1)](https://blog.tri-sen.com/tag/api670) - [MTTF (1)](https://blog.tri-sen.com/tag/mttf) - [PTI (1)](https://blog.tri-sen.com/tag/pti) - [TSODS (1)](https://blog.tri-sen.com/tag/tsods) - [axial compressor (1)](https://blog.tri-sen.com/tag/axial-compressor) - [compressor efficiency (1)](https://blog.tri-sen.com/tag/compressor-efficiency) - [hydraulic trip (1)](https://blog.tri-sen.com/tag/hydraulic-trip) - [incipient surge (1)](https://blog.tri-sen.com/tag/incipient-surge) - [overspeed detection (1)](https://blog.tri-sen.com/tag/overspeed-detection) - [polytropic (1)](https://blog.tri-sen.com/tag/polytropic) - [proof test interval (1)](https://blog.tri-sen.com/tag/proof-test-interval) - [stonewall (1)](https://blog.tri-sen.com/tag/stonewall) - [surge curve (1)](https://blog.tri-sen.com/tag/surge-curve) - [surge detection (1)](https://blog.tri-sen.com/tag/surge-detection) - [surge margin (1)](https://blog.tri-sen.com/tag/surge-margin) - [temperature control (1)](https://blog.tri-sen.com/tag/temperature-control) - [trip block (1)](https://blog.tri-sen.com/tag/trip-block) [See all](https://blog.tri-sen.com#) ** HELP ###### HeadQuarters - North America  Engineering 109 Magellan Circle Webster, TX 77598 Tel:  +1-832-632-1211 Fax: +1 281-724-1226 ###### Netherlands Verlengde Zuiderloswal 4 Hilversum, NH 1216 BX Tel: [+31 88 011 9292](tel://+31%2088%20011%209292) ###### Singapore 56 Kallang Pudding Road #06-10 HH@Kallang  Singapore 349328 Tel: +65 6381 9188 Fax: +65 6381 9199 ### Search ** ### Stay in Touch - [** ** ](https://www.linkedin.com/company/tri-sen-systems-corporation/) [Privacy Policy](https://tri-sen.com/privacy) | [Terms and Conditions](https://tri-sen.com/terms) Copyright © 2019. 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