GHM Martens TB225, Руководство по эксплуатации

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6 Function Test
When operating the device at a high request rate, i.e. in the event of process-
related frequent response to the device, additional functional tests can be dis-
pensed with in accordance with IEC 61508. This also applies to operation
with a low request rate, i.e. in case of process-related rare response of the
device. The probability of failure is very low for 10 years of service according
to SIL2 (see table on page 26).
For a functional test, the temperature sensor / current / voltage is simulated with a simula-
tor. In the case of thermocouples, the inputs may be connected in parallel.
The test starts with the check of the temperature monitoring. In the good area, the relay
must be active.
It is then tested
- the consistency of the temperature displayed on the TB225 display with that of the
simulator at each test step
- the alarm function when leaving the good area of the temperature
- the alarm function in case of sensor breakage (each line disconnected) and sensor
short circuit.
A correct alarm function of the TB225 is given when
- the relay is deactivated and the contact takes the resting position,
- the respective error in the display is displayed correctly as plain text,
- the display lighting of the TB225 changes to "red",
After the temperature has been changed back to the good range with the simulator, a
correct function of the TB225 is given when in the operating mode temperature limiter
- the relay is only activated again after a reset has been made in the menu or a
- external RESET button has been pressed,
- after which the display shows the normal operating data,
- the display lighting of the TB225 switches back to "white",
if in the operating mode temperature monitors
- the relay is activated without a reset in the menu or an external RESET button being
pressed,
- the display shows the normal operating values,
- the display illumination of the TB225 changes back to "white";
Warning!
If the relay is not deactivated during one of the test steps, or the temperature or
fault rate is not displayed correctly in the display, the TB225 must be sent to the
factory for inspection.
In the meantime, the plant must be kept in a safe condition by other means.
Warning