0:13
about level transmitter output current
0:17
signal status with respective to tank
0:22
level we simulated tank level from 0
0:27
percentage to 25 percentage then then
0:30
50% then 75 and finally 100% right so
0:38
now the tank level is 100
0:40
percentage we will use the same concept
0:43
to understand analog output okay I will
0:50
concept now previously the tank level is
0:55
percentage and to drain the water inside
0:59
the tank I will use one
1:04
okay this pump speed we can
1:12
output generally this analog output will
1:20
substation okay or electrical devices
1:24
vfd variable frequency drive
1:30
this drive will control the pump or
1:35
supply so that we can control the pump
1:39
speed okay for simple understanding I am
1:44
not discussing those things I'm just
1:47
simply say the PLC analog output
1:54
speed and the pump speed range is 0 to
2:01
here I will use percentage 0 to 100
2:05
percentage for measuring the speed of
2:09
pump so that we can understand easily
2:14
that is why I'm using percentage
2:16
otherwise in Industries they will use
2:26
given without giving start the pumps
2:29
generally it will not start even though
2:32
analog output is there okay that is why
2:35
start is given by the
2:38
PLC and operator controlling the pump
2:43
manually so that he can enter the set
2:47
point the required speed on the graphics
2:51
let's say the operator entered set
2:55
point0 percentage okay then p C sends 4
3:01
milliamp analog output to the
3:04
pump then the pump is started but it is
3:09
it will not rotate because it is still 4
3:12
milliamp only that is why the measured
3:19
percentage okay let's say the operator
3:23
increases the set point set point means
3:26
the required pump speed value
3:30
the operator enters the set point here
3:34
then from the computer the set point
3:37
will go to the PLC via this
3:41
communication and the
3:44
PLC receives the set point from the
3:48
computer then calculates the set point
3:53
value and converts it into the current
3:57
signal in the range of 4 4 to 20
4:02
milliamp then the PLC sends that current
4:06
signal to the pump okay that is why this
4:11
is analog output PLC sending the analog
4:16
output sending the current signal to the
4:20
output devices like pump I mean vfd
4:26
okay if you don't know about vfd no
4:30
problem just consider like
4:33
this based on the analog output value
4:37
the pump speed will be
4:39
controlled if the analog output is 4
4:42
milliamp pump speed is
4:46
0% and when analog output is 20 milliamp
4:53
100% okay for beginners it is easy to
4:57
understand that is why I am using
5:02
okay now the operator increases the set
5:06
point okay now the operator given 25%
5:11
point this set point it will go to the
5:16
communication and then PLC calculates
5:19
the equivalent analog output current
5:22
value then sends that current value to
5:25
the pump that means to the vfd
5:29
8 milliamp is received that is why the
5:33
pump is started okay that means the pump
5:38
rotating that means there is some speed
5:40
value so the measured speed is right now
5:44
25% the water is started draining and
5:50
reducing after some time the tank level
5:55
75% okay now the operator again
6:02
point now it is 50 percentage the 50
6:06
percentage value they entered in the
6:10
Graphics that's 50% set point it will go
6:14
PLC again the PLC calculates the
6:20
signal and the current signal again it
6:33
increased again water is draining out
6:36
now the tank level reaches
6:40
50% again operator increases the speed
6:44
75% what happens P again updates the
6:48
current signal value accordingly which
6:52
milliamp then the pump speed again
6:56
increases now it is 75%
7:03
reducing now the tank level is
7:07
25% now the operator given maximum set
7:10
point which is 100% of
7:13
speed PLC again calculates the current
7:16
signal which is 20 milliamp it will go
7:21
pump then the pump speed reaches maximum
7:24
value which is measured speed is
7:27
100% now the tank level redu uses
7:30
again now it reaches the minimum value
7:35
10% then the PLC immediately stops the
7:40
pump okay in Industries
7:45
generally uh it will not go to the 0%
7:48
tank level okay they will stop at
7:50
minimum level 5 percentage 2 percentage
7:53
10 percentage depending on the process
7:57
okay that is why PLC immediately given
8:01
stop command then the pump is
8:04
stopped when the stop is given
8:07
respective of the analog output
8:10
value the pump will be
8:13
stopped stop has the highest priority
8:17
okay so this is the concept for analog
8:22
output based on 4 to 20
8:27
milliamp thank you I will meet you in
