Endress+Hauser Gammapilot M FMG60 - Behavior of Device When in Operation and in Case of Failure

Gammapilot M
10 Endress+Hauser
Dangerous undetected failures in this scenario:
A dangerous, undetected failure is defined as an incorrect output signal which deviates from the real measured
value by more than 10 %, with the output signal remaining within the range of 4 to 20 mA.
Diagnostic test interval:
The internal diagnostic test interval of the Gammapilot M is 15 minutes. During this time, all internal safety
functions are executed at least once.
Useful lifetime of electrical components:
The established failure rates of electrical components apply within the useful lifetime as per IEC 61508-2.
section 7.4.9.5 note 3.
!
Note!
In accordance with DIN EN 61508-2, Note NA4, appropriate measures taken by the manufacturer and
operator can extend the useful lifetime.
!
Note!
Correct installation is key to the safe operation of the Gammapilot M.
Behavior of device when in
operation and in case of failure
Behavior of device when switched on
Once it has been switched on, every Gammapilot M goes through a diagnosis phase lasting maximum
120 seconds.
During this time, the current output is at error current ≤ 3.6 mA.
During the diagnosis phase, communication via the display interface or via HART is not possible.
Once the diagnosis phase has been successfully completed, an uncalibrated device sets the current output to
error current ≥ 21 mA and retains this value until calibration has been completed.
Once calibration has been successfully completed, the device switches to measuring mode (current output:
4 to 20 mA).
If an internal device error is detected during the diagnosis phase, the current output remains at error current
≤ 3.6 mA.
If an internal device error is detected during calibration, the current output remains at error current ≥ 21 mA.
Once the diagnosis phase has been successfully completed, an already calibrated device switches to
measuring mode (current output: 4 to 20 mA). Otherwise, it remains at error current ≤ 3.6 mA.
!
Note!
• If a calibrated Gammapilot M is cut off from its power supply, the internal clock is buffered for at least 6 days.
After this time, it may be necessary to reenter the current date and time. This is indicated by error current
≥ 21 mA and error message A635.
To enter the date and time, the device must be unlocked and then locked again (see Operating Instructions
BA00236F/00/EN Appendix "Operating menu for point level detection").
• To activate the safety functions, the Gammapilot M must be locked directly after calibration (see "Method
for device parameterization" → ä 15).
Behavior of device on demand
Once the maximum level is reached, the radiation is absorbed by the medium in the tank. The output current
is set to 20 mA. The rise time corresponds to the configured output damping
τ (1 to 999 s; default value 6 s)
plus the device-internal dead time. The device-internal dead time is dependent on the configuration of the
"Beam type" function.
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Caution!
Please also note the Section "Output damping" in the Operating Instructions BA00236F/00/EN.
Setting Menu selection "Basic setup", Function "Beam type" Device-internal dead time
Standard 1 s
Modulated 4 s