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  1. #1
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    For Osiyo on HMI Design

    Quote Originally Posted by sysint View Post
    Osiyo, the problem had nothing to do with the control scheme.

    I'm thinking:
    • The specifier didn't have anything in the specs about specific PM for critical components.
    • The responsible people did not have a baseline correct running conditions and energy consumption specified.
    • The HMI was improperly designed because it could not identify an issue with a critical sensor drifting and proper system operation.


    So, really the installation group is the biggest failure here and not the building staff or control scheme.
    Fair enough statements, as far as they go.

    -- The engineer who did the operational design, did in fact specify in his paperwork that the CO2 sensors be checked periodically. With no more than 5 years between checks. As suggested by the manufacturers of the sensors.

    Now, the original install and programming job was not mine. But in my run through of sensor checks I did talk to one of the maintenance staff members who remembered that when they'd attended the training session one of our guys provided at end of project, periodic checks of CO2 sensors was mentioned and discussed. AND ... I looked at our archive files. And found that we'd bought the school district a test and calibration kit as part of the project.

    I eventually located it. In one of their store rooms. A district level maintenance staff member remembered they had it. It was still sparkly, shiny brand new ... having never been used.

    --As far as "responsible" people having and knowing baseline correct running conditions. Depending on the specific school in question, when I queried folks some had a clue what background ambient CO2 might be. Most did not. Some had learned the numbers, back when, but couldn't recall them. Some were new replacements for guys now gone, who'd never been told or read up on it.

    Most, just never gave the subject much thought. Or none at all.

    Keep in mind that at many sites, the in-house maintenance people are at minimum numbers and have many other duties besides HVAC system maintenance and monitoring. As one guy, head of maintenance for a significant building, told me ... he spent the majority of his time with "bricks and mortar and misc hardware" stuff.

    Fixing chairs and desks, the stuck drawer in a filing cabinet, leaky plumbing fixture, lock that doesn't work, trim work that was loose, carpet or floor tile needing attention, burnt out light bulbs or starters, etc. Neither he nor his staff had time to be looking at BAS screens, unless someone was complaining or some alarm was going off.

    Just for info, system was keeping historical data and trends. It was all available. Covering the entire period that DDC system had been installed. Several of the maintenance folks said that in fact, at first, they'd looked at that data from time to time.

    But it was a LOT of numbers. And things seemed to be working just fine. And no one had time to just sit around and analyze what all those 10's or 100's of thousands of numbers were telling them. Few had the technical background, in depth, to really USE the info.

    So they'd finally just stopped paying attention to that stuff or looking at it. Except when someone complained. Then only looked at the specific data related directly to the complaint.

    One site maintenance sup mentioned to me that at first after the install of their DDC systems, at the district level their top guy in charge of HVAC and Electrical services HAD routinely collected the historical/trend data and actually looked at it and analyzed it. Took some actions as a result. But he'd retired. His replacement? Well the DDC conversion project hadn't been his toy. As far as he was concerned, it was a done deal. So, as I find to be normal for such things and people in the higher up positions, he spent his time and energies concentrating on something else. HIS pet concerns and projects. Something different, that he could tack his name on as HIS idea. So that if he succeeded, he could make name for himself, claim credit, and be in a position for promotion or pay increase.

    And, as such things go, if the new boss wasn't pressing them about it, individual maintenance staffs in the various buildings sort of let all that data collection just continue without a look or much thought.

    I'm not singling out this specific customer school district.

    I see this same sort of thing ALL the time. Other school districts (we do about a dozen); city, county, state, and federal governmental agencies; and businesses.

    There are, of course, exceptions. i.e. One county for whom we do all their controls. Their head of mechanical and electrical systems is an ex-HVAC service guy, turned HVAC business owner, turned into county employee. Who is sharp, knows his stuff, and has the ability to convince the upper county officials to listen to him, to provide adequate staff, etc. He has a counterpart over in one of the school districts we serve, with similar background and attitude.

    And, of course, we have several more serious private businesses we serve, mostly process control related (i.e. a pharmaceuticals manufacturer) who have excellent in-house staff in adequate numbers. Add a couple casinos who ensure they've got very good staff, both to ensure the comfort of the customers, and to maximize net profit margins.

    But for most customers we deal with ... if somebody isn't griping or alarms going off, etc ... they hardly pay attention. And staff hasn't time to just sit around and look at screens, data records, etc.

    Keep in mind that those of us who hang around these forums, live and breath this stuff. Think about it all the time. Its what we do for a living. Most of us would almost instantly spot the sort of issues mentioned. Its second nature to most of us.

    i.e. Its rare that I get a complaint call and go to a site in response, where I won't incidentally while troubleshooting the specific complaint, spot another half dozen or a dozen issues. Happens all the friggin time.

    Yesterday I was on a site where we're doing a front end conversion. Changing over from what Automatrix calls a Sage, to a Matrix and Facility Server system. (Somewhat similar to the Tridium AX type of system)

    A large commercial building, 36 floors not counting 3 level basement. Had originally had a Barber-Colman Network system, years ago was gradually converted over to Automatrix. That stuff is working fine, some of it 10 years old or older. But the front end stuff is dated, no longer made, etc. The building controls have been done by various contractors over the years, before we became their sole controls contractor. So we have a problem that we were just not to sure how accurate our info was about what controllers were where, what was really connected to what I/O (various folks in the past made changes but left no documentation), what were all the running programs doing and why, etc.

    So my part of the task was to audit and verify the installed controls, points, programs resident in controllers and programs running on the front end, etc. Make changes as necessary. i.e. IAW our standard procedure, move as much programming and control into the unitary controllers as possible. We like things to be as "stand alone" as possible. Especially in large, complex installations.

    Anyway, net result was that I was looking at everything. And spotting an almost endless list of possible issues with equipment. Have been keeping a list. Will present to customer to see if they'd like us to fix it or will fix it themselves.

    Haven't found a problem with any controllers themselves. Altho customer's guys have told me that they thought this or that problem was with the controllers/programming. They've been wrong. Everything they've pointed out has been something they should've/could've fixed. i.e. Faulty/failed sensor, out of cal sensor, pneu actuators not properly linked or with leaking diaphragm, VFD they replaced themselves but didn't set up right, dirty coils, dampers needing some work or replacement, valves leaking by, etc etc.

    And I've spotted a bunch of stuff they didn't recognize as an issue.

    But ... I don't really fault them. I do this for a living, full time. Those systems are something they deal with pretty much only upon complete failure or a comfort complaint.

    When I talk to them explaining this or that issue, light bulb lights up in their eyes, they follow my logic. Just hadn't thought about whatever on their own. Most of their focus is upon stamping out fires, fixing this or that other thing ... an endless and never ending list, etc. I think that if they'd more time, and experience, to look and think about what they were seeing on the screens, they'd have figured at least most of it out. But they don't.

    FWIW, that school district with the CO2 sensor issues? Listened to us. Now have hired an energy audit service to do routine audits and checks to spot things they've not seen or overlooked or didn't recognize as an issue. Folks, who like myself, think about this sort of stuff all the time.

    --As concerns the installers and controls company not doing an adequate HMI. That's PERHAPS true.

    However, in my experience HMI's are like anything else. They're spec'd and a price agreed upon. We have a "standard package", with one price. Anything more than that, is an extra. Price goes up. I've sat in meetings with customers where we presented various extra options (somebody has to spend the time to create those), where we proposed and suggested this or that extra feature, and our reasoning behind it. Just to have customer take a pass on it.

    We're not in the habit of spending an extra 50% of manhours to add stuff ... for free. And it might seem silly that in a controls contract with a total price tag of $1 to $2 million that a customer would haggle over an extra 20 - 40 hours of front end programming ... but they'll sure as heck do it.

    As far as end of project baseline data collection and such, its done. But what customer does with it, or even if they look at it at all is in their ball park.

    We make suggestions. We don't come back and insist they follow our suggestions.
    A site where I stash some stuff that might be interesting to some folks.
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  2. #2
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    Hi Osiyo,

    If your customers do not <insert scenario here> then your HMI needs to identify.

    Identification is not reams of trends and pictures to sift through.

    You stated: "However, in my experience HMI's are like anything else. They're spec'd and a price agreed upon. We have a "standard package", with one price. Anything more than that, is an extra. Price goes up. I've sat in meetings with customers where we presented various extra options (somebody has to spend the time to create those), where we proposed and suggested this or that extra feature, and our reasoning behind it. Just to have customer take a pass on it."

    I would reply that maybe you should examine your HMI base package. Does it contain many mostly useless trends and pictures? Then maybe your base package needs to be redesigned. Isn't the bigger problem you cannot sit in a room with your guys and determine a way to display your HMI that is really beneficial?

    I examine specs and note oftentimes these specifications contain meaningless trends. And, a commissioning agent will spend needless hours verifying they are all there. The customer gets this overburdened HMI and doesn't know how to run it. However, this same customer can get into his relatively complicated car and for most issues it tells him what's wrong and he can operate it rather simply.

    Obviously you know the problems. What's the solution? My take is that you identify a bad system trend or problem. With the CO2 sensor issues can you tell me what metrics tell you that this sensor is not reading correctly? Well, those value ranges should be identified on the drawing the guy would look at. When the values go beyond acceptable range indicators this means there is some sort of issue. Why wasn't there a popup on the screen tracking hours that came up and said "calibrate me NOW dammit!" instead of waiting for Mayhem to show up?

  3. #3
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    For Osiyo on HMI Design

    Hi Osiyo,

    If your customers do not <insert scenario here> then your HMI needs to identify
    .

    Identification is not reams of trends and pictures to sift through.

    You stated: "However, in my experience HMI's are like anything else. They're spec'd and a price agreed upon. We have a "standard package", with one price. Anything more than that, is an extra. Price goes up. I've sat in meetings with customers where we presented various extra options (somebody has to spend the time to create those), where we proposed and suggested this or that extra feature, and our reasoning behind it. Just to have customer take a pass on it."

    I would reply that maybe you should examine your HMI base package. Does it contain many mostly useless trends and pictures? Then maybe your base package needs to be redesigned. Isn't the bigger problem you cannot sit in a room with your guys and determine a way to display your HMI that is really beneficial?

    I examine specs and note oftentimes these specifications contain meaningless trends. And, a commissioning agent will spend needless hours verifying they are all there. The customer gets this overburdened HMI and doesn't know how to run it. However, this same customer can get into his relatively complicated car and for most issues it tells him what's wrong and he can operate it rather simply.

    Obviously you know the problems. What's the solution? My take is that you identify a bad system trend or problem. With the CO2 sensor issues can you tell me what metrics tell you that this sensor is not reading correctly? Well, those value ranges should be identified on the drawing the guy would look at. When the values go beyond acceptable range indicators this means there is some sort of issue. Why wasn't there a popup on the screen tracking hours that came up and said "calibrate me NOW dammit!" instead of waiting for Mayhem to show up?

  4. #4
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    I look forward to constructive conversation generated by this thread

    I am kind of on all sides of this one.

    1. I designed the HMI for my building and definitely want it to be useful and look professional.

    2. I am the building engineer and have to use the data and have my staff be able to decipher the display and data.

    3. We are just starting a LEED certification for our building and will be implementing a good bit more data trending.

    Part of my fear with the LEED certification process is that beyond the LEED cert all that trending and data will just start to be unimportant.

    So.... I am very interested in hearing how different people implement trending that is truly beneficial long term. How people manage data long term and how to design the HMI to make it useful to even a low level building engineer.
    I want to know when fluffy is sick.

  5. #5
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    Quote Originally Posted by sysint View Post
    Hi Osiyo,

    If your customers do not <insert scenario here> then your HMI needs to identify.

    Identification is not reams of trends and pictures to sift through.

    You stated: "However, in my experience HMI's are like anything else. They're spec'd and a price agreed upon. We have a "standard package", with one price. Anything more than that, is an extra. Price goes up. I've sat in meetings with customers where we presented various extra options (somebody has to spend the time to create those), where we proposed and suggested this or that extra feature, and our reasoning behind it. Just to have customer take a pass on it."

    I would reply that maybe you should examine your HMI base package. Does it contain many mostly useless trends and pictures? Then maybe your base package needs to be redesigned. Isn't the bigger problem you cannot sit in a room with your guys and determine a way to display your HMI that is really beneficial?

    I examine specs and note oftentimes these specifications contain meaningless trends. And, a commissioning agent will spend needless hours verifying they are all there. The customer gets this overburdened HMI and doesn't know how to run it. However, this same customer can get into his relatively complicated car and for most issues it tells him what's wrong and he can operate it rather simply.

    Obviously you know the problems. What's the solution? My take is that you identify a bad system trend or problem. With the CO2 sensor issues can you tell me what metrics tell you that this sensor is not reading correctly? Well, those value ranges should be identified on the drawing the guy would look at. When the values go beyond acceptable range indicators this means there is some sort of issue. Why wasn't there a popup on the screen tracking hours that came up and said "calibrate me NOW dammit!" instead of waiting for Mayhem to show up?
    I don't disagree with you at all.

    And I do have a voice, and a vote about these things.

    But its only one vote. And while a number of others agree with me, we haven't gotten an adequate number of votes to make that change occur.

    Some others, who might also agree, have voted "Nay" simply on the principle that in the current market and economic situation .... we're already having to exist on slimmer profit margins than the board of directors would wish for. ANY change that'd mean an increase in man hours spent on a project is viewed with disfavor.

    I don't see this changing until the market improves. One way or the other. Either by a better economy, or by competitors knuckling under and giving us a bit more leeway in asking a couple or 3 percentage points extra profit. The later may happen. While our profit margins are way down, we're still paying the bills and making money. While a few of our competitors have gone bye-bye. And in a couple other cases we've taken some major accounts away from a couple major players locally. They scr*wed the pup and pi**ed off the customers.

    So we'll see.

    But right now, we're in the minimalist mode. Bidding projects with slim margins. No one wants to propose anything to the higher ups that'll trim another 1% off. Not that we actually have to request permission first. Could just do it. But then my boss would have to explain that additional loss at end of project, and he wouldn't like that.

    Things are picking up tho. Slowly, but surely. Maybe I'll get the group to think it over again by this fall.
    A site where I stash some stuff that might be interesting to some folks.
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  6. #6
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    Quote Originally Posted by sysint View Post
    You stated: "However, in my experience HMI's are like anything else. They're spec'd and a price agreed upon. We have a "standard package", with one price. Anything more than that, is an extra. Price goes up. I've sat in meetings with customers where we presented various extra options (somebody has to spend the time to create those), where we proposed and suggested this or that extra feature, and our reasoning behind it. Just to have customer take a pass on it."

    I would reply that maybe you should examine your HMI base package. Does it contain many mostly useless trends and pictures? Then maybe your base package needs to be redesigned. Isn't the bigger problem you cannot sit in a room with your guys and determine a way to display your HMI that is really beneficial?
    We do indeed review our HMI base package on a regular basis. We review most of our standards and the way we do things routinely.

    As a group, we are always seeking suggestions for ways of doing things better. Even with the current economic hard times, and having to work with slimmer profit margins, upper management doesn't just quietly allow, they actively promote and encourage our monthly Tech-Talk meetings. Which range from a couple hours up to 4 hrs. Where we all get together and discuss issues, concerns, suggestions for doing whatever a better way, trade things learned, new and better techniques, and so forth.

    This is not time devoted to discussing active contracted projects. Time for that is done and billed to the project concerned. And generally only includes the particular folks concerned. Tech-Talk time is, officially, "non-productive" time. We're not talking about specific issues related to a specific job. Its attended by anywhere from 15 to 25 folks (some will not attend due to other commitments which they can not reschedule). Techs, engineers, and usually one or more of the management types.

    So it is a not an insignificant expense for "non-productive" time. At the cost per head per hour to the company, you can pretty much figure that each such meeting costs them from over $2500 to over $5000. Not counting time spent before and after by some. Who'll be drumming up lists of discussion points and issues to be addressed; some guy or guys who'll be preparing material for making their case; and time spent afterward sifting through notes taken in the meeting, deciding on actions to be taken, drafting a "Meeting Report and Summary" ... which is drafted, cleaned up and sent to all via email. So each person has a record of anything decided, what was discussed, requests that someone volunteer to take the initiative to gather more data, so forth and so on. And so those who had to miss the meeting are kept in the information loop.

    So the Big Boss is in fact committed to the department MAKING time to do this sort of thing. And willing to attend those meetings where he has to stand in front of the company Board of Directors and justify the "non-productive" time expense. He does take hits and dings and gaffs as a result. He and I don't always see eye to eye, but he's good people. Ex-HVAC type who went on to get his degree and moved into upper management.

    But to get something done, to initiate change isn't so simple ... many times ... as just proposing it and making your argument/justifications.

    Everybody and their brother can come up with something "new", find fault with a previous method, etc. That, really, takes no particular talent, skill, or extra intelligence.

    Especially so amongst that crowd.

    We have some folks doing controls who are relative newbies. Mostly over on the service side. Only 5 years or so. Most of the people present have been doing this stuff for 10 to 20+ years. And are inclined to look at things from an experienced, practical, and pragmatic point of view.

    Mention most anything, and the kind of things they're gonna ask is pretty much focused upon:

    -- How much extra time or expense is this gonna cost us?

    -- How difficult is it to implement, then test and verify?

    -- How reliable is it, long term?

    -- What's our increased liability?

    -- What is the REAL ... lets see some hard data ... benefit to us and the customer versus the hassle and costs of making this change.

    So forth and so on.

    Keep in mind that amongst that crowd you've got at least a couple centuries worth of accumulated experience at seeing "the next new, better idea ... that turned out to be just not all that good."

    And they're all basically tech-geeks who've seen just about every sort of the "latest and greatest", whiz-bang, gadget or idea thought of. And have seen a lot of them turn out not to be just all-that.

    So you have to convince them, and get buy in from the majority to get things to actually happen. And, depending on what it is you're suggesting ... that can be a chore.

    Once you get them to buy in, next step is to get management, which includes the salesmen (who are all ex-techs/engineers), to buy into it if its gonna cost more than the current methods.

    Generally speaking, if you can make your case at the Tech-Talk meeting and get the buy-in of those folks, the management/salesmen level will give it the thumbs up. Most of the time.

    Just laying out how these things work where I work. You're not talking to the semi-literate or ill informed, or customers who barely know more than what the short articles in a trade magazine say. You're addressing peers, every bit as smart as yourself, as experienced or even more so, who understand all the bits and bytes talk. As well as the nuts and bolts.

    Now, any of us could just decide to "do" it, whatever new idea it is we have. Its not like management is looking over our shoulders and/or nitpicking us on everything. We're actually given a lot of latitude and leeway.

    But if you do just decide to go ahead with a new idea, without group buy in, its your baby. And responsibility. Better be ready to take the heat if it fails, customer doesn't like it (company policy is that someone will make it good, regardless of cost), or if it significantly impacts bottom line at the end of the project. Hard questions will be asked, and you'd better have some good answers.

    Its not as if you're immediately kicked out onto the street in such cases. Has happened. As in the case when one guy's "better idea" cost us $350,000 plus a really ticked off customer. But most times, you're just raked over the coals a few times, get your tally-whacker whacked, and are told to think a LOT HARDER about it ahead of time before proceeding along with what seemed like a good idea at first blush. In short, next project had better have better bottom line results.

    That basic HMI package we offer as a standard, has been thought over and thought over, reviewed, examined, and does undergo change over time (slowly). And tested with LONG term customers. Folks we've had recurring projects with for 10 years or better.

    Every single item in it has had a great deal of thought put into it. Thought ... and experience with feedback from customers. We even have standards for such things as color schemes, default resolutions, size of screens, button and widget types for the various purposes, terminology for labeling, general layout plans for the various type screens, etc.

    The "standard" is used for various reasons.

    One, it represents our company. Customer gather impressions about your competency based upon what they see. Nice looking, professional looking, functional and usable screens reflect well upon you. Tends to also give customer impression that you probably spent as much attention to detail at installing the actual controllers, programming, etc.

    It's also almost a sort of trade mark thing. We DO NOT put our company name on any of those screens. After all, the equipment and systems now belong to the customer. Screens have customer organization names shown.

    But if you've seen our HMI's, you'll recognize them any other time you see one. Appearance, layout, general scheme, methods employed, general color scheme, etc are always consistent. There is an unmistakable "sameness" to them regardless of platform or system used. AAM, TAC, whatever. Proprietary front end, or JACE, etc.

    We KNOW, from experience, just about how long each screen for each type of equipment, subsystem, or whatever in that basic package is gonna take a man to make. This makes it easier to estimate manhours, etc.

    We KNOW, that in 95% of the cases, basic package will cover 90% or better of customer wants, needs, and expectations. For smaller and/or less demanding customers, it usually exceeds expectations. HMI programmer just has to be concerned with that odd ball 5 to 10% which will require "extra" time because he's starting from scratch.

    It works for us. The VAST majority of our customers are quite pleased with the results. In most cases, that "standard" ends up saving us time and man power.

    So we don't dink with it much. Not without some sort of logical justification. Suggested changes are reviewed closely by a whole room full of folks. Folks who've been doing this sort of thing, hands on, for as long as you or I ... or longer.

    Quote Originally Posted by sysint View Post
    I examine specs and note oftentimes these specifications contain meaningless trends. And, a commissioning agent will spend needless hours verifying they are all there. The customer gets this overburdened HMI and doesn't know how to run it. However, this same customer can get into his relatively complicated car and for most issues it tells him what's wrong and he can operate it rather simply.

    Obviously you know the problems. What's the solution? My take is that you identify a bad system trend or problem. With the CO2 sensor issues can you tell me what metrics tell you that this sensor is not reading correctly? Well, those value ranges should be identified on the drawing the guy would look at. When the values go beyond acceptable range indicators this means there is some sort of issue. Why wasn't there a popup on the screen tracking hours that came up and said "calibrate me NOW dammit!" instead of waiting for Mayhem to show up?
    No argument. But will address this specific part of your post later. Have to get moving for today's work.

    Sorry, about the delayed response, just noted this thread this morning after getting ready for work and sitting down for a cup of coffee.
    A site where I stash some stuff that might be interesting to some folks.
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  7. #7
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    Merged (3) post's from the VAV reset thread into this thread as requested

  8. #8
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    I have what may be a simple question with regards to this and the original thread. I went back and looked at the few programs I've done with CO2 and I see I am alarming on a CO2 less than 400 ppm for over an hour, but I did not consider a high. For a high add based on drift I am thinking a CO2 greater than my ventilation set point for more than 24 hours. At the location this is at I don't see 24 hour time frame being an issue, but maybe I am missing something. I just don't want to add another 'nuisance' pop alarm. The other location I am thinking for over a week, but I'll have to check the trends since it is a smoking area. Thoughts?
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  9. #9
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    Crab - Why do you use a low CO2 alarm, to indicate over ventilation and wasted energy? If so, that's a good point that we don't do.

  10. #10
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    Quote Originally Posted by tlp261 View Post
    Crab - Why do you use a low CO2 alarm, to indicate over ventilation and wasted energy? If so, that's a good point that we don't do.
    Hmmm, agreed good point

    Always done just a High alarm here, but ya got me re-thinking things

  11. #11
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    Low is more so if it goes to 0 due to a cut wire/device dies, or I could use the thought if the calibration starts to waiver too low.

    BTW may base CO2 on these other buildings has always been no less than 500 ppm.
    Last edited by crab master; 02-28-2011 at 05:04 PM. Reason: BTW

  12. #12
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    Quote Originally Posted by crab master View Post
    Low is more so if it goes to 0 due to a cut wire/device dies, or I could use the thought if the calibration starts to waiver too low.

    BTW may base CO2 on these other buildings has always been no less than 500 ppm.
    I do a sensor failure check here, but never thought about a lower then average alarm. This could very well indicate an issue, such as a stuck OD damper or something...

  13. #13
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    Well on a typical 0-2000 ppm sensor i would alarm anything below 350 or so just based on average OA is typically higher than that. Most places i see are more 400-450 baseline OA. So if you see a sensor sitting at 350 or less i would assume its failing or not calibrated correctly.

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