1 00:00:01,570 --> 00:00:02,860 Hello and welcome. 2 00:00:02,950 --> 00:00:09,910 In this last one we are going to talk about resisters and how you can identify for this story is in 3 00:00:09,910 --> 00:00:10,620 good shape. 4 00:00:10,630 --> 00:00:18,760 All of this is broken now if it is a good resister the marginal value must be within the range of the 5 00:00:18,770 --> 00:00:27,790 rated value that measured value using an o meter or monthly meter that measure the value using an o 6 00:00:27,790 --> 00:00:35,960 meter or a multimeter is a way to draw mind that is a store value in a circuit. 7 00:00:35,960 --> 00:00:43,670 Another way is using the color band so we can remind the resistance of that is a store using that as 8 00:00:43,670 --> 00:00:48,680 a store color coding as you can see each of these colors 9 00:00:51,340 --> 00:00:52,710 indicate something. 10 00:00:52,720 --> 00:01:01,210 So if the color came in the first digit as you can see for the four band resistor One two three four 11 00:01:01,600 --> 00:01:08,560 or five and resistor each color means something if it Black was the first digit. 12 00:01:09,160 --> 00:01:12,330 This means that the first value is zero. 13 00:01:12,790 --> 00:01:21,070 If Black is the second digit then this means that the second value is zero same for third. 14 00:01:21,100 --> 00:01:24,760 And here we have a multiplier and tolerance. 15 00:01:24,760 --> 00:01:27,850 So let's say that we have this resistor. 16 00:01:27,850 --> 00:01:30,020 Yellow means number four. 17 00:01:30,040 --> 00:01:32,440 So we can write for up here 18 00:01:35,740 --> 00:01:37,130 as you can see here. 19 00:01:37,570 --> 00:01:39,250 The second color is purple. 20 00:01:39,250 --> 00:01:40,330 It has number seven 21 00:01:43,370 --> 00:01:45,830 so we are going to write several here. 22 00:01:45,980 --> 00:01:53,380 The third digit here in this case is is the multiplier in a fourth band color code. 23 00:01:53,420 --> 00:02:00,220 We have two digits and a multiplier and a runs value in five bands. 24 00:02:00,230 --> 00:02:04,230 We have three digits a multiplier and utterance value. 25 00:02:04,250 --> 00:02:07,010 So the third digit is not usable. 26 00:02:07,010 --> 00:02:09,620 Here are the four band code. 27 00:02:09,620 --> 00:02:12,850 So they are going to use the multiplier. 28 00:02:13,250 --> 00:02:24,090 And the orange means 1000 so three zeros and the tolerance is this color which is gold. 29 00:02:24,300 --> 00:02:27,030 And it will be plus or minus 5 percent. 30 00:02:27,060 --> 00:02:39,750 So it will be 74 or 47 kilo because we have three zeros on with a tolerance plus 5 percent now in the 31 00:02:39,750 --> 00:02:42,740 five band we will do the same thing. 32 00:02:42,780 --> 00:02:44,930 The green is number five. 33 00:02:45,090 --> 00:02:51,550 So we write five down here that Brown is number one as you can see here. 34 00:02:51,660 --> 00:02:53,450 So write one down here. 35 00:02:53,640 --> 00:03:01,300 And since it's five band code we will use the third digit which is black and it will be zero. 36 00:03:01,320 --> 00:03:04,720 And the red for the multiplier means 100. 37 00:03:04,770 --> 00:03:06,850 So we will add two zeros. 38 00:03:06,870 --> 00:03:13,940 And here we have a brown which means 1 percent tolerance and you add 1 percent tolerance. 39 00:03:14,010 --> 00:03:17,870 So it will be 51 three zeros. 40 00:03:17,880 --> 00:03:21,700 Means kilo on that's it. 41 00:03:21,700 --> 00:03:26,100 This is how to use color coding to identify that as a store value. 42 00:03:26,140 --> 00:03:32,520 And this is the best way to identify as a store value inside a board without having to remove it. 43 00:03:32,530 --> 00:03:40,510 Now to know if that resistance is working or not you have to measure the color using the color code. 44 00:03:40,510 --> 00:03:50,840 Then you have to break out one of the two legs for that was a store from your board and measure it using 45 00:03:50,990 --> 00:03:52,220 a digital multimeter. 46 00:03:52,580 --> 00:04:00,230 And if these two values match the color coding value and the digital multimeter value if there was a 47 00:04:00,230 --> 00:04:03,930 match between them this means that this was a store is working properly. 48 00:04:04,400 --> 00:04:06,080 And there is no problem in it. 49 00:04:06,620 --> 00:04:16,790 So what you need to know is that you need to find these store values and the color code and you need 50 00:04:16,790 --> 00:04:26,160 to match it with the digital multimeter value if these two are the same means that the resistor is working 51 00:04:26,160 --> 00:04:26,770 just fine. 52 00:04:27,430 --> 00:04:32,780 Otherwise mean that you have a problem and you need to fix that problem. 53 00:04:32,790 --> 00:04:40,580 Now one thing that you need to know is that you can't measure the resistance using as additional multimeter. 54 00:04:40,680 --> 00:04:43,460 Why that is a store is still on board. 55 00:04:43,470 --> 00:04:50,610 So you have to disassemble or disorder one of the two terminals of that resistor so that you can measure 56 00:04:50,610 --> 00:04:57,600 it correctly because sometimes when you measure it while it's still on board you might end up measuring 57 00:04:57,600 --> 00:05:03,510 it with other components connected to it parallel or Syria. 58 00:05:03,510 --> 00:05:12,110 So this will cause a reading error and to avoid this we usually recommend this all during one of these 59 00:05:12,110 --> 00:05:19,880 two terminals and removing them from the board and then you can test it or majority using dual digital 60 00:05:19,880 --> 00:05:21,620 multimeter. 61 00:05:21,620 --> 00:05:30,440 Now in order to cover this in more details these are some examples for a physical appearance of that 62 00:05:30,860 --> 00:05:38,320 effective or defective resistor now as you can see this is how hard it is to lock when it is burned 63 00:05:38,320 --> 00:05:40,540 out completely. 64 00:05:40,540 --> 00:05:45,910 This is a slight burn out but yes you can still recognize the coloring. 65 00:05:45,910 --> 00:05:47,820 Here you can three guys anything. 66 00:05:48,670 --> 00:05:52,550 So if you saw it as this thought that looks like this in a board. 67 00:05:52,570 --> 00:05:57,880 This means that this resistor is broken and you have to replace it. 68 00:05:58,180 --> 00:06:06,190 So in order to measure out of the story using all this that is losing a digital multimeter you might 69 00:06:06,190 --> 00:06:17,320 end up with three results open shorted or change value open meter deflection indicates infinite resistance 70 00:06:17,380 --> 00:06:17,870 reading. 71 00:06:17,920 --> 00:06:21,880 This means that that resistor is broken entirely. 72 00:06:21,880 --> 00:06:29,890 And these two terminals are no longer connected together shorted meter deflection indicates zero resistance 73 00:06:29,890 --> 00:06:30,650 reading. 74 00:06:30,730 --> 00:06:36,850 This means that this resistor is now like our eye are connected and it doesn't have any value. 75 00:06:37,240 --> 00:06:38,760 It's just zero resistance. 76 00:06:38,770 --> 00:06:45,240 So it's like shorting two terminals are positive and negative and connecting them directly together. 77 00:06:45,250 --> 00:06:53,670 Now the third but rarely happen incident is change that is the change in our resistance value. 78 00:06:53,680 --> 00:06:59,670 Rare defect of a resistor measure the value is not within the range of the rated value. 79 00:06:59,680 --> 00:07:06,960 So it is I think you're on with this story might measure it and read five kilo on resistor. 80 00:07:07,030 --> 00:07:09,540 This is not a very common case. 81 00:07:09,670 --> 00:07:14,760 Usually it's either open or shorted but it might happen. 82 00:07:14,830 --> 00:07:16,540 It's very rare but it might happen. 83 00:07:16,540 --> 00:07:24,430 So you need to know that it's there to make sure that before this thing at a distance you d all that 84 00:07:24,430 --> 00:07:31,150 one of these two terminals from the circuit or you can disorder the whole resistance and twisted outside 85 00:07:31,180 --> 00:07:36,220 then put it back or resold it to the board. 86 00:07:36,820 --> 00:07:37,980 That's it for this lesson. 87 00:07:37,990 --> 00:07:42,660 If you have any questions regarding the resistance these ask like you aren't able. 88 00:07:43,120 --> 00:07:43,810 Thanks for watching. 89 00:07:43,810 --> 00:07:46,150 This is Ashley from educational engineering team.