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XT-1000
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 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 current consumption in failure mode (see Figure 8)
Unscrew sensor head cap (1) using an open-ended spanner.
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 sensor is 16
mA. After 5 seconds, the LED stops flashing and indicates the current consumption value
for failure mode for 2.5 seconds: if the LED lights up permanently, I
failure
= 21.5 mA; if the
LED goes out, I
failure
= 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 the change.
To set a current consumption of 3.6 mA during the dwell period (10 s) in failure mode
briefly press “4 mA” button (2) (0.1 to 2 seconds).
To set a current consumption of 21.5 mA during the dwell period (10 s) in failure mode
briefly press “20 mA” button (3) (0.1 to 2 seconds).
The new measuring range configuration is not stored until the
level sensor reverts from adjustment mode to configuration mode
automatically and the LED goes out. The new configuration is re-
tained even if the level sensor is subsequently disconnected from
the power supply.
Screw sensor head cap (1) back on.
If, during operation, the level sensor detects that the level cannot be
output correctly due to an insufficient supply voltage, it enters failure
mode and sets current consumption to 3.6 mA (regardless of any failure
current settings).
Summary of Contents for XT-1000
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