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Page 15/37 Adjustment
− briefly press (0.1 to 2 seconds) “4 mA” button (2) to define a current consump-
tion of 4 mA at this position
− briefly press (0.1 to 2 seconds) “20 mA” button (3) to define a current consump-
tion of 20 mA at this position
When the “4 mA” button is pressed, the LED goes out for 5 seconds. When the “20 mA”
button is pressed, the LED lights up permanently for 5 seconds.
The sensor then remains in configuration mode for a further 15 seconds before storing the
change and reverting to measuring mode.
The new measuring range configuration is not stored until the level sensor
reverts automatically from adjustment mode to configuration mode and the
LED goes out. The new configuration is retained even if the level sensor is
subsequently disconnected from the power supply.
For “dry” settings to be possible in the case of bypass sensors, a magnetic
system with spacer bracket will need to be obtained from the manufacturer
of the bypass. Configuration can then be carried out even with the sensor
removed.
6.2 Current consumption in failure mode
If a malfunction is preventing the level sensor from recording a plausible float position, i.e.
the measured level is incorrect, the sensor will enter the failure mode after a short time.
Failure mode signalling conforms to the NAMUR NE43 recommendation. The failure current
is set by default to 21.5 mA but this value can also be set to 3.6 mA.
To configure the current consumption in failure mode (see Figure 11).
(1) Unscrew probe head cap (1) using an open-ended spanner.
(2) Press and hold both the “4 mA” (2) and “20 mA” (3) simultaneously for at least 3
seconds.
Green LED (4) “Cal/Err” flashes rapidly. The current consumption of the level sen-
sor is 16 mA. After 5 seconds, the LED stops flashing and indicates the selected
failure current consumption for 2.5 seconds. If the LED is on permanently, I
failure
is
21.5 mA; if the LED turns off, I
failure
is 3.6 mA. If no button is pressed again, the
level sensor remains in failure mode for a further 2.5 seconds before reverting to
measuring mode and discarding any changes.
(3) To set a current consumption
− of 3.6 mA during the dwell time (10 sec) in the fault mode, briefly press the
"4 mA" (2) button (0.1 … 2 seconds).
− of 21.5 mA during the dwell time (10 sec) in the fault mode, briefly press the
"20 mA" (3) button (0.1 … 2 seconds).