Electronic level sensor
LR7009
33
12 Applications
12.1 Minimum level monitoring with early warning and alarm
Switching output 1: early warning
SP1
slightly above rP1 (to suppress wave movements)
rP1
below preset level
Ò
early warning, start refilling
OU1
hysteresis function, normally closed (Hnc)
Switching output 2: alarm
SP2
min. value reached again
Ò
alarm reset
rP2
below min. value
Ò
alarm
OU2
hysteresis function, normally open (Hno)
XX.X:
display value
A:
early warning
B:
alarm
•
If the level is below rP1, output 1 switches until liquid is refilled. If SP1 is reached again, output 1 is
reset.
•
If the level is above SP2, output 2 switches. If the level falls below rP2 or if there is a wire break,
output 2 is reset.
•
By setting SP1 the maximum level can be controlled / monitored: the value of SP1 determines up
to which level (max.) liquid is to be refilled. When the maximum level is reached, this is signalled by
the LED OUT1 going out and output 1 resetting.
12.2 Pumping station / empty the tank with overflow prevention
Switching output 1: control to empty tank
SP1
upper value exceeded
Ò
submersible pump ON
rP1
lower value reached
Ò
submersible pump OFF
OU1
hysteresis function, normally open (Hno)
Switching output 2: overflow prevention
SP2
maximum value exceeded
Ò
alarm
rP2
slightly below SP2 (to suppress wave movements)
OU2
hysteresis function, normally closed (Hnc)