D5093-TB
- SIL3 24/220Vdc/Vac Transistor-Out Detector
G.M. International ISM0541-2
6
The proof test shall be performed to reveal dangerous faults which are undetected by diagnostic. This means that it is necessary to specify how dangerous undetected faults, which
have been noted during the FMEDA, can be revealed during proof test. The Proof test consists of the following steps:
Testing procedure at T-proof
Steps
Action
1
Bypass on input the module channels under test, taking appropriate action in order to avoid a false trip, and use the safety-related PLC to read channel output
state during the test.
2
Connect a variable DC / AC source to any input terminals couple (7-8 for D5093S-TB and 7-8, 9-10 for D5093D-TB).
For each channel, during normal operation, when the input DC / AC voltage amplitude is comprised between 15 Vdc / Vrms and 250 Vdc / Vrms (maximum
allowed value for the module safe operation) and the appropriate threshold is selected, by means of the internal dip-switch, in accordance with the applied input
signal, the output transistor is in the closed state, as detectable by the safety-related PLC, and the yellow channel status LED is lit. A safe failure is present if the
output transistor is in the open state instead of the closed state.
Then, when the input DC / AC voltage amplitude falls below the related lower threshold value, the output transistor turns to the open state, as detectable by the
safety-related PLC, and the yellow status LED is turned off. A dangerous failure is present if the output transistor is in the closed state instead of the open state
and two possible dangerous fault situations could be happened:
1) if the channel status LED has been turned off, then the output transistor is in short circuit;
2) if the status LED is lit again, then the comparator stage threshold has been excessively lowered and the output transistor is again energized.
Repeat this test for all of the five possible threshold voltage levels (each one of them corresponds to a different position of the dip-switch selector).
3
Restore the loop to full and normal operation, removing the bypass on input the module channels under test.
This test reveals almost 95 % of all possible Dangerous Undetected failures in the module.
Configuration
D5093-TB
ON
ON
CH. 1
CH. 2
(for D5093D-TB)
Threshold level 1
(24 Vac/Vdc typical)
1 = ON, 2 = 3 = 4 = 5 = OFF
1 2 3 4
ON
OFF
DIP switch configurations (all valid for SIL applications):
5
Threshold level 2
(48 Vac/Vdc typical)
2 = ON, 1 = 3 = 4 = 5 = OFF
1 2 3 4
ON
OFF
5
Threshold level 3
(60 Vac/Vdc typical)
3 = ON, 1 = 2 = 4 = 5 = OFF
1 2 3 4
ON
OFF
5
This mode is
factory settings
Threshold level 4
(110 Vac/Vdc typical)
4 = ON, 1 = 2 = 3 = 5 = OFF
1 2 3 4
ON
OFF
5
Threshold level 1
(220 Vac/Vdc typical)
5 = ON, 1 = 2 = 3 = 4 = OFF
1 2 3 4
ON
OFF
5
DIP switch positions 6 to 8 are not used.
