Functional Test Procedure - nVent RAYCHEM Elexant 5010i Bedienungsanleitung

3.1.4 Setting the limiter temperature set point
3.1.4.1 Choosing a set point
EN
The lock out temperature (set point) of the safety limiter must be set in such a way that the maximum allowable temperature of the
DE
equipment is not exceeded. For example, the surface temperature of a heat-tracing cable in a hazardous area cannot exceed the local
maximum temperature allowed based on the classification rating (T-rating) of the area. The set point should be the maximum allowed
FR
temperature less 5°K for temperatures below or 200°C, or less 10°K for temperatures greater than 200°C.
RU
3.1.4.2 Configuring the limiter set point
Modifying the set point requires physical access to the Elexant 5010i device. The lock out set point may be configured with any
supervisory software that allows the user to be physically close to the 5010i device. The procedure to modify the limiter set point is the
same for all user interfaces. Use your preferred configuration method to enter the set point and then press the SET button on the
Elexant 5010i device to confirm the set point change.
The SET button can be accessed by unscrewing and removing the top cover. The button must be pressed within 30 seconds after the
new setpoint has been entered. If the button is not pressed before this time interval has elapsed, the new value is discarded and the old
set point value remains unchanged. Once the new set point has been saved, it can be confirmed by holding the SET button, and reading
the setpoint (in °C) off the LED display.
3.1.5 Main output interlock
When the safety limiter output is off, for any reason, an internal signal overrides the output of the main output switch, to force it off.
The main output can only be switched on if the limiter temperature sensor is connected, and the measured temperature is below the
limiter set point. There is no user action required for this feature, and it cannot be disabled.
3.1.6 Internal diagnostic
The internal power to the limiter circuit is continually monitored by the limiter microprocessor. Any detected instability is reported to the
user via a status flag on the user interfaces. There is no known effect on the safety function in the presence of a detected power failure.
As a precaution, if the limiter power failure flag is persistent or recurring regularly, follow the instructions in Section 3.1.13 – Response to
Fault Conditions.
3.1.7 Functional test
The Elexant 5010i Safety Limiter units meet the requirements of SIL2 (see Section 3.1.11 PFDavg Safety Function for more details)
as set out in IEC61508:2010. In accordance with this standard, units are subjected to a functional test after commissioning and at
regular intervals, in order to guarantee safe and reliable operation. The test interval for the safety limiter can be set to 1, 10 or 20 years,
depending on the application. The functional test procedure is described in Section 3.1.8 – Functional Test Procedure. Conformance to
the SIL certification is limited to the 20-year lifetime of the unit.
Type
5010i-Mod-IS-LIM
Table 2 - Functional Test
3.1.8 Functional test procedure
The functional test is performed after commissioning and at regular intervals over its operational lifetime, to ensure it is still capable
of carrying out its intended safety function. This check requires a voltmeter capable of reading the output heater voltage, and a short
length of wire (5 cm/2 in).
Setup the functional test using these steps:
1. Reset any limiter-related trips.
2. Clear all alarms.
3. Ensure the controller output (and the HEATER LED) are on. The Control Mode can be switched to "Force ON" if required.
4. Setup check: Measure the voltage to the heater at the output terminals Lo and No, to verify the output is ON.
Execute the functional test by performing the following steps:
1. Disconnect one of the limiter RTD leads (sensors).
2. Result: The ALARM and LIMITER LEDs light up, and the HEATER LED switches off.
3. Check for OFF: Measure the voltage to the heater at the output terminals Lo and No, to verify the output is off.
4. Reconnect the limiter RTD (sensor). Wait about 10 seconds for the temperature reading to return on local display.
5. Press the RESET button.
6. Clear all alarms.
7. The HEATER LED is now on, the ALARM and LIMITER LEDs are off.
8. Check for ON: Measure the voltage to the heater at the output terminal, to verify the output is on.
9. Install a wire bridge between the W/B and rightmost R positions to simulate a short across the limiter RTD (sensor).
Wait about 10 seconds for the short to be detected.
10. Result: The ALARM and LIMITER LEDs light up and the HEATER LED switches off.
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12 nVent.com/RAYCHEM
Safety Integrity Level Systematic Capability
SIL 2 SC 2
Proof Check Interval Unit Lifetime
1, 10, or 20 years 20 years