1 00:00:00,360 --> 00:00:06,750 Well before we get started programming alarms we're going to talk about something that's even more important 2 00:00:06,750 --> 00:00:14,930 and more fundamental and that is consideration before we start putting any logic into a program. 3 00:00:14,940 --> 00:00:25,050 The first thing we really need to do is stop and think and plan how to program alarms and notifications 4 00:00:25,380 --> 00:00:27,650 for each and every system. 5 00:00:27,660 --> 00:00:35,580 The reason is there are several factors that you want to consider and not all alarms and notifications 6 00:00:35,670 --> 00:00:36,850 are alike. 7 00:00:37,230 --> 00:00:43,030 The first consideration on a programmer's mind is always safety. 8 00:00:43,470 --> 00:00:49,890 What alarms do we absolutely have to have no matter what. 9 00:00:49,950 --> 00:00:53,220 What are the alarms that have to be in our program. 10 00:00:53,460 --> 00:01:02,550 And obviously for anything critical we want to notify an operator but there are limits to all of these 11 00:01:02,550 --> 00:01:03,590 things. 12 00:01:03,810 --> 00:01:09,910 We don't need an alarm for every single thing that happens in our system. 13 00:01:09,930 --> 00:01:18,840 There are certain things that don't affect the process that don't endanger anybody they don't damage 14 00:01:18,840 --> 00:01:19,970 equipment. 15 00:01:20,100 --> 00:01:29,820 And even though you have an analog signal coming in you might not need a high high and or low low alarm 16 00:01:29,820 --> 00:01:37,660 condition just because you know how to program and LLN and H.H. doesn't mean you need to. 17 00:01:37,710 --> 00:01:39,390 Every single time. 18 00:01:39,570 --> 00:01:47,250 Also you want to be particular about what notifications you provide your operators if you give them 19 00:01:47,310 --> 00:01:53,480 an abundance of notifications for everything that happens every day in a system. 20 00:01:53,520 --> 00:01:59,370 They're probably going to start looking at them after a few days in which case anything important that 21 00:01:59,370 --> 00:02:04,380 you try to notify them of is going to be lost and they're not even going to know what happened. 22 00:02:04,410 --> 00:02:10,800 They're going to hit a reset button here a clear button hit an acknowledged button and make your important 23 00:02:10,830 --> 00:02:15,960 notifications disappear with all the garbage that you decided to put into the system. 24 00:02:16,140 --> 00:02:21,810 Just because you know how to do it more is not always the merrier. 25 00:02:21,900 --> 00:02:24,420 You have to take consideration. 26 00:02:24,510 --> 00:02:27,770 What does the operator need to know. 27 00:02:27,770 --> 00:02:32,220 What does the operator want to know what's beneficial. 28 00:02:32,400 --> 00:02:35,400 What is going to keep people safe. 29 00:02:35,460 --> 00:02:40,360 What's going to keep the system running the way that it's supposed to be running. 30 00:02:40,500 --> 00:02:46,890 Take into consideration how your alarms are actually going to function and how your notifications are 31 00:02:46,890 --> 00:02:48,990 actually going to function. 32 00:02:49,020 --> 00:02:55,890 For instance if a problem occurs at 3:00 in the morning when nobody is monitoring a system let's say 33 00:02:55,890 --> 00:02:58,490 a part of your system is going to shut down. 34 00:02:58,710 --> 00:03:05,160 Well if that condition resolves itself automatically do you really want to leave the system shut down 35 00:03:05,160 --> 00:03:11,850 for six hours until somebody comes in to look at it or if the problem goes away on its own and it's 36 00:03:11,850 --> 00:03:13,580 nothing too critical. 37 00:03:13,620 --> 00:03:17,760 Would it be smarter to let the system go ahead and resume operation. 38 00:03:18,150 --> 00:03:23,730 Well consider that system might be filtering drinking water for a small community. 39 00:03:23,760 --> 00:03:28,890 Do you really want them to wake up in the morning and not be able to take a shower because maybe at 40 00:03:28,890 --> 00:03:34,770 one point in the night your tank level got a little too low that's going to seem really silly when the 41 00:03:34,770 --> 00:03:39,960 operator comes in in the morning and the tank is full and everybody's yelling at them because they don't 42 00:03:39,960 --> 00:03:41,030 have any water. 43 00:03:41,160 --> 00:03:46,350 Obviously if the tanks are running low that's something the operators are going to want to know about 44 00:03:46,400 --> 00:03:46,510 . 45 00:03:46,560 --> 00:03:52,920 Maybe he's going to need a larger pump or a secondary pump for times of high demand. 46 00:03:53,010 --> 00:03:59,000 On the other hand you don't want to leave the system shut down if it's not critical. 47 00:03:59,010 --> 00:04:05,760 On the contrary if you have a boiler that's getting out of control and heats up to a high high set point 48 00:04:06,210 --> 00:04:12,960 you probably do want to shut the system down and leave it down until an operator comes in physically 49 00:04:12,960 --> 00:04:15,020 interacts with that system. 50 00:04:15,060 --> 00:04:17,460 Otherwise somebody could die. 51 00:04:17,850 --> 00:04:23,940 So while consistency is oftentimes desirable especially when it comes to a learning curve for a new 52 00:04:23,940 --> 00:04:32,040 system if you have 20 or 30 alarms it's not necessarily reasonable that all 30 of those alarms are going 53 00:04:32,040 --> 00:04:34,450 to work exactly the same. 54 00:04:34,500 --> 00:04:38,760 Some of those conditions might be able to reset themselves. 55 00:04:38,970 --> 00:04:46,950 Others might require an operator to interact some of those notifications can probably be silenced. 56 00:04:46,980 --> 00:04:53,730 So they're not perpetually annoying an operator on the other hand some of those notifications might 57 00:04:53,730 --> 00:04:58,120 be a little bit more persistent and depending on the nature of the condition. 58 00:04:58,410 --> 00:05:05,380 So before we start programming before we started dropping logic and XICs and TEONs. 59 00:05:05,580 --> 00:05:06,830 Let's take a minute. 60 00:05:06,840 --> 00:05:08,570 Consider our process. 61 00:05:08,610 --> 00:05:17,490 Consider our operators needs and really think hard about what alarms do we need how are those alarms 62 00:05:17,490 --> 00:05:20,970 going to work what notifications do we need. 63 00:05:21,060 --> 00:05:28,590 Who's going to see those notifications and so on and so forth doing that in the beginning is not only 64 00:05:28,590 --> 00:05:35,260 going to save you a lot of rework down the road it's also going to make you a much more popular programmer 65 00:05:35,280 --> 00:05:38,970 with your own company and with your customers as well.