Lead Commissioning Engineer-Instrument | 20+ Years Exp. | Mcdermott (Aramco & Qatar LNG Offshore) | PACO | ICSS | Oil & Gas | Onshore & Offshore | PMC | Survey Expert | Completions & Testing | Expeditor | Refinery | MOC
I thought of posting Q&A's related to Oil and gas commissioning to our Linked in members (Elect, Inst, Mech Etc). This will helpful to share our experience and thoughts. You can also share your knowledge / questions thro message to post in my page. It will be useful for young commissioning engineers ..! Question# 1 What are the types of Smoke / Flame detectors available in the market? and how to configure pre-warning/Alarm prior to Trip or High High for these detectors (Conventional and 4-20 mA)? Follow for more.... #commissioning #commissioningengineer #oilandgasindustry #oilandgas #interviewtips #construction #instrumentation #instrumentationandcontrol #dcs #esd #firesafety #Fireandgas
Hi Sudan, Most multisensor detectors are available in the market. You can detect smoke and heat. Both of these functions are working in a multisensor detector. Firstly if you want to set the trip or high. Then you need to know the temperature trip set value in 4-20 mA or you can do data logging with Smoke and flame detectors to check temperature value compared with mA and you can set trip values of devices in SCADA & PLC System.
Hi Sudhan, we have various products with various type sensor technology and outputs it is depending on what kind application, fuel, fire hazards, specification, local standard & rules etc based on that sensor technology to be determined. As I said there are various type sensor technology are available in the market but Today's most industries are using optical technology sensor for smoke detector and Multi spectrum (Triple IR) flame detector those are available (depending manufacturer) with proprietary addressable type outputs, digital or potential free contact outputs and conventional analog (4-20mA) output. Determining of pre-alarm and Alarm to be advised by customer, their local guideline, safety and engineering team based on cause and effects sheet. Hope this we will helpful information. Thanks for posting such queries.
Smoke detectors types are based IO signal type and area of configuration ( outdoor, ex proof, duct mount). The most of the cases pre-warning alarms won’t be available in smoke detectors, on detection it will spike high high.
Smoke detectors are part of fire and gas system, they are used to mitigate the event occured. Hence pre alarm are not provided. Even smoke detectors of 4-20mA are not generate linear value. They’re genarating discrete value only.
Lead Instrument Commissioning Engineer - KBR
5moSD and FD pre-alarm isn't required and not useful because the trigger time is short. Generally SD comes as a digital signal 0/1. Pre-alarm can only be set for the HSSD(VESDA) For earlier detection of the air flow, filter,...etc.