A few trips ago we had some alarm issues on the tug, and I’d like to see what you guys think from both a deck and engineering point of view.
Random alarm acknowledged by chief, investigated, manual pressure guages on machinery say there’s no fault. Alarms continue to say otherwise. Manual gauge from opposite machinery swapped out to rule out a bad gauge. All spec’s correct. Alarm is being triggered every 10 minutes, every 30 seconds, every hour, distracting the whole crew from their jobs as well as preventing rest. It’s likely a bad sender, but who are you to make that assumption and bypass an alarm, lest the machinery blow up for the very fault being erroneous reported at the time? [I]Allegedly,[/I] in this case its not as simple as checking for open/closed switch in the sensor.
So…what do you do?
Bypass it, take a the risk of a casualty and take the blame?
Hope to get someone in the office to sign off and then bypass it?
Listen to alarms all day and all night?
Tie boat up until you can get a vendor there? (and look for a new job)
After talking with his engineering boss in the office (2200 on a Saturday), the chief got ahold of a support engineer in a far away country. They sent instructions on bypassing the alarm in one of the junction boxes, and with shore-side’s blessing this was done. Quiet alarms until we get a new sender.
How do you guys feel about these immensely complicated vessel alarm systems. For fucks sake we can’t open a water tight door and fully dog it without an alarm, that encourages crew to either not makes rounds through spaces, OR not completely dog doors. In one way it creates a ton of reliance on the system, as hell, if a mouse farts in the engine room we get an alarm, why the hell make rounds and check things? Then when there’s a problem, the boat is nearly crippled by sirens and beeps.Same for acknowledging the same alarm, if the same exact thing happens so many times, the alarm system should have some logic to back down and issue a more subtle “check engine light” or something, after the chief has determined it is not an issue.
Very good question. “Back in the Day”, when there were larger crews onboard, I remember seeing so many toothpicks jammed into “Alarm Silence” buttons that the control console looked like a denuded forest. . . . That said, the watch standing crew could keep track of the machinery displaying the alarm conditions to verify that the signal was erroneous. Even when I sailed as the sole engineer (Crowley), there were the rare occasions where I would pull a relay on an alarm that was in error. Of course now, with scaled back crews (for the most part), unmanned engine rooms, the Alarm System takes the place of the diligent, experienced watch stander. I would seriously doubt that a system design would also publish a protocol for disabling alarms, yet that would appear to nullify the need for a system in the first place. Ultimately, the onus falls on the shoulders of the Chief Engineer. At least I can safely say that during my tenure as Chief, I never had a serious failure result from any alarms that I bypassed. Probably didn’t sail long enough. . . . Anytime that I DID bypass an alarm condition, I also made sure that they affected system/machinery was noted and particular attention was paid during rounds. Tough question with no particularly right answer. Falls do the judgment of the engineer.
I know your pain, I would silence the alarms till the new one arrives. 9/10 nothing downstairs is going to happen but monitoring closely till the new part arrives should do
What rshrew said but I’d go one step further. Monitor and document. Write up instructions for the crew making rounds and make an entry in the log (or start a separate sheet) showing that you’ve taken steps to mitigate the risk of the disabled alarm. Instead of just of writing the usual “rounds made, all in order” or some such add a specific observation. For example “rounds made, all in order, E/R bilge level 0 inches” (or whatever)
It’s a pain but it will get PSC inspector off your back.
What type of alarm system? What alarm point is being triggered? What type of sensor/transducer? For the most part there shouldn’t be anything you can’t check/test yourself with equipment onboard. Not everyone carries a heat pot onboard unless they are doing the old fry daddy trick. Other than that you should be able to test your stuff.
No idea. It's a hydraulic pressure sensor in the propulsion system. I'm told it measures a small swing (hundred) in pressures in the many thousands of PSI. When we had the reps onboard in shipyard they had digital hydraulic pressure gauges that could show these small changes and log them for display, something we don't have. It's small tolerance stuff from my understanding.
Another problem with too much complexity, too many computer controlled systems, too much networking, too many computerized alarms.
We have so many similar sounding alarms that are so networked together, that it sometimes completely disrupts safe navigation, and can take several minutes to find out what is causing half a dozen different alarms to ring at the same time. You cannot put a toothpick in these touch screen panels to stop the alarms.
I used to design and install Automation / Alarm Systems back in the day. When my company installed the newest and best (???) Computer System to monitor all of our systems we had all kinds of Ghost Alarms. I worked really close with the Engineer / Designer / Installer when he the install on my boat. I was lucky enough that he trusted me and gave me the program to get into the software, which made it possible to see the real data not just what was shown on the readout panel.
If I was Chief on the boat in question, I would have replaced the sensor with a spare with the same ratings. If no spare was onboard, I would have them overnight one to the vessel. If this is a Computerized System there should be some way to either change the alarm points or disable the problem child sensor. The last thing that I wanted as the designer of a system was having a False Alarm sounding so much the everyone ignores any future Alarms, which could lead to some serious problems down the line.
Any and ALL Chiefs should pester their Port Engineers to get them all of the Training that is available. Also, if whatever system is being used the Company should make sure that it can be troubleshot over the Phone!
Back in the 80’s and 90’s there was a Company from the Norfolk VA area named Pan Am (If I remember Correctly) that was infamous for building systems that ONLY they could fix. I caught them splicing wires in a big bundle with a different color wire which made tracing them almost impossible. Also, they went so far as making you replace a printed circuit board just because of a burned out bulb.
[QUOTE=z-drive;156817]No idea. It’s a hydraulic pressure sensor in the propulsion system. I’m told it measures a small swing (hundred) in pressures in the many thousands of PSI. When we had the reps onboard in shipyard they had digital hydraulic pressure gauges that could show these small changes and log them for display, something we don’t have. It’s small tolerance stuff from my understanding.[/QUOTE]
99.99999% of the time it will be a loose connection on a terminal strip or DIN rail block. Especially on new equipment. The problem is usually right in front of our faces but we tend to look for the more complex. A regiment of tightening connections should be done every time a panel or Jbox is opened.
[QUOTE=z-drive;156817]No idea. It’s a hydraulic pressure sensor in the propulsion system. I’m told it measures a small swing (hundred) in pressures in the many thousands of PSI. When we had the reps onboard in shipyard they had digital hydraulic pressure gauges that could show these small changes and log them for display, something we don’t have. It’s small tolerance stuff from my understanding.[/QUOTE]
If you can’t fix it with a hammer you have an electrical problem. Log it, do a proper JSA for heavens sake, get emails to management so you have some type of cover your @$$ paperwork, then put a plan in place to monitor the system while the alarm is “muted”. Paperwork fixes everything!
Last year, I made a trip on a brand new ship loaded with alarms and boy did they go off like crazy. Always running down to check the engines every few minutes, etc. Problem was she was a newbuild under warranty and you just don’t bypass alarms on something like that. Eventually we had to bypass a low level alarm in the sewage holding tank because it went nuts in even a little weather after you pumped down (the MSD was not working…another story…we were outside of the limits). But the engines we just had to keep silencing because being so new, there could either be a real issue or just a “bug.” You don’t want to be the one to screw things up.
There is a Pan-American alarm system on here, not a pleasant sight. Actually in its day it was state of the art but its been a serious pain in the ass. I know another chief on a new PB+J boat with sensors up the ass and he has had alot of trouble, unfortunately due to the reduction in man power we rely on automation. You take the average engineer and throw him into an Intercon panel and he just scratches his head, some of these newer systems are very PLC + relay heavy and even im stumped most of the time.
The boat I’m on currently has a consolidated touch screen alarm system that goes off about once every two hours for various false triggers. More frustrating than that is that the panel displays what it’s sensing is wrong but doesn’t show the actual value, i.e. oil pressure, temperature, etc. So much for the convenience of remote monitoring. Luckily there is a silence button nearby.
That being said, I once ran for 5 hours listening to a computerized voice tell me that the intake air temp was too high (it wasn’t) because all of the engine alarms were tied into the same computer and I didn’t want to turn the volume down and risk missing a legitimate alarm. Hitting the silence button didn’t work in this case because the values from the sensor were fluctuating and would set the alarm off again. As soon as I could I learned how to disable the sensor and did the c.y.a. paperwork.
[QUOTE=injunear;156841]99.99999% of the time it will be a loose connection on a terminal strip or DIN rail block. Especially on new equipment. The problem is usually right in front of our faces but we tend to look for the more complex. A regiment of tightening connections should be done every time a panel or Jbox is opened.[/QUOTE]
Correct ! Likely a loose connection. Should be SOP to check connections whenever you open a box. You could feed a signal from the sensor or install a resistor across it and see if it still happens. If so it is just like injunear said and a loose connection or you could just check all connections. You should have a spare sensor on board if the system is critical.
Spurious alarms must be corrected or people quit paying attention after awhile.
There are so many little things overlooked in alarm systems. It helps to have a basic understanding of electrical principles. Are the sensors NO or NC. Current loops? Someone mentioned Intercon. Their PLC control is very basic. Learning how ladder logic works and following the input and output indicators pinpoints the area of fault. Improper clearance of magnetic pick-ups and misaligned proximity switches are big culprits.
Technology advances at a faster rate than we can piss and moan about it. I remember several questions on my electricians exam in 1971 about carbon pile regulators.
[QUOTE=injunear;156967]There are so many little things overlooked in alarm systems. It helps to have a basic understanding of electrical principles. Are the sensors NO or NC. Current loops? Someone mentioned Intercon. Their PLC control is very basic. Learning how ladder logic works and following the input and output indicators pinpoints the area of fault. Improper clearance of magnetic pick-ups and misaligned proximity switches are big culprits.
Technology advances at a faster rate than we can piss and moan about it. I remember several questions on my electricians exam in 1971 about carbon pile regulators.[/QUOTE]
Carbon pile? damn you are old if you even remember that [I do]
It is true that the technology is advancing but it is also true the guys don’t either have the background or the training to advance with it. Sadly, when they budget for all the new technology to cut labor they do not budget for the training to maintain it.
Sometimes you can reset alarm set points in the software or time delays to stop harassing alarms. You can hook your amp meter in series with the sensor and find out what kind of output you are getting from the sensor ( usually 4-20 milliamps) for a pressure transducer and check alarm settings for that alarm and see where it alarming at. You can "off scan/inhibit/or remove wires in terminal strip to stop the alarm too. You should fix the problem when you determine whether it is a hardware or software problem.
I once had a USCG test procedure changed because it was impossible to do. The head pressure from a freshwater cooling system when off was 43 psi at the pump suction (giant engineroom on a tanker) and the standby pump was supposed to start at 37 psi. The pressure at the pump would never be 37 due to static head unless you lowered the head tank. That ship was 16 years old when I found the problem when setting standby pressure switches with a calibration hand-pump.
Yes, getting to know the system is invaluable. When Crowley bought the Robin tugs in the mid 80s, I spent quite a bit of time in the yard with them and also with the guys who were installing the new alarm system. I not only learned the alarm settings, but also the code to access and change them. Flash forward a few years and I was back on one of them on the West Coast. I was getting a nagging alarm (forget which one now), but was able to enter the system, saw what was setting the alarm off, changed the alarm points and logged it. Got into port and had everything fixed.