CARLO GAVAZZI LDD1 Manual De Instrucciones página 25

8.4 Fail Safe and Fail Secure mode
In case of a broken wire in the loop wire or loss of power to the Loop Detector, the fail Safe/Secure
function allows the user to decide which position the output relay should change to.
Failure mode set to secure
ON
POWER
OFF
Yes
LOOP FAULT
No
Yes
VEHICLE
No
Closed
OUTPUT (NO)
Open
Closed
OUTPUT (NC)
Open
Failure mode set to safe
ON
POWER
OFF
Yes
LOOP FAULT
No
Yes
VEHICLE
No
Closed
OUTPUT (NO)
Open
Closed
OUTPUT (NC)
Open
In Fail Secure mode the output relays operate normally while there are no issues in the application. If
an error is detected or power to the Loop Detector is lost, the outputs will always fall back to default
output state which is no vehicle detection in the loop. This function can be used if it is important to close
the gate or barrier in case of problems.
In Fail Safe mode the output relays operate inverted while there are no issues in the application. This
means that the Normally Open (NO) relay contact becomes Normally Closed (NC) and the Normally
Closed (NC) relay contact becomes Normally Open (NO). If an error is detected or power to the Loop
Detector is lost, the outputs will always fall back to default output state which is detection of a vehicle
in the loop. This function is used if it is important to open the gate or barrier in case of problems.
Note: If power is returned to the product while a vehicle car is parked on top of the loop, the Loop
Detector will not activate. Only a new vehicle entry will generate an activation.
Rev.00 - 03.2019 | LDD1/LDD2 Single and Dual Loop Detector | © 2019 | CARLO GAVAZZI Industri
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