Configuration; Safety Function Of The Limiter In The Elexant 5010I-Lim - nVent RAYCHEM Elexant 5010i Bedienungsanleitung

1.1.6 Configuration
The Elexant 5010i controllers can be configured locally by means of a handheld programming device or from a central location using the
NGC-UIT/TOUCH 1500 or Supervisor Software. After programming, all settings are permanently stored in the nonvolatile memory of the
Elexant 5010i control unit, avoiding loss of data in the event of power failure or after a long-term power shutdown.
2. MAINTENANCE
Equipment placed into hazardous areas needs to comply with IEC/EN 60079-17 regarding inspection and maintenance requirements.
The IEC/EN 60079-17 describes in more detail the requirements regarding documentation, qualifications of personnel, inspections,
regular periodic inspections, continuous supervision by skilled persons, maintenance, isolation of apparatus, earthing and inspection
schedules.
3. SAFETY TEMPERATURE LIMITER
3.1 Safety limiter
The safety limiter option (-LIM option of the Elexant 5010i, see Table 1 - Elexant 5010i Variants) provides a redundant high temperature
cut-out mechanism, suitable for use in safety critical applications. It disconnects power from the heater, preventing the system from
exceeding a safe temperature level.
3.1.1 Safety function of the limiter in the Elexant 5010i-LIM
The safety function is invoked when the temperature limit is reached, or in the event of a fault (such as sensor break, sensor
short-circuit, component failure, or supply failure) even when the process conditions are within the permissible temperature range.
The safety function disconnects power to the attached equipment without delay.
Power may be restored to the attached equipment by manually resetting the safety function after the temperature returns below the
permissible limit, and no fault is present. The safety function may be reset using the RESET button on the front of the unit, or through
supervisory software connected via the communication ports or via handheld android device over Bluetooth.
In specific circumstances where there is no current flowing through the heat trace during the over-temperature event, the limiter will
self-reset once the temperature returns below the permissible limit and no fault is present.
3.1.2 Area of use
Safety limiters are used in areas where thermal processes need to be prevented from overheating, and where the system must be set to
a safe operating condition in the event of a fault. A typical example of such an installation is surface heating in a hazardous area.
3.1.3 Resetting the safety limiter
The safety limiter is designed such that after it has tripped, resetting it is possible only after the normal, safe operating conditions are
returned. If there was no current flowing through the heat trace at the time of the over-temperature condition, the safety limiter will reset
itself without user intervention. If there was current present in the heat trace during the over-temperature condition, then the device
needs to be manually reset.
In order to manually reset the limiter after it has tripped, the user needs to press the RESET button, under the lid of the Elexant 5010i
enclosure (shown in the Figure below). Alternatively, the limiter can be reset remotely using Supervisor software, Android tablet, or other
supervisory software. Refer to the operating manual for the supervisory software for detailed instructions on how to remotely reset a
safety limiter.
nVent RAYCHEM Elexant 5010i-LIM
HEATER
ALARM
LIMITER
RS485
BLUETOOTH
RESET
Limiter reset button (rearm the limiter after it has tripped)
SET
Limiter temperature set button to be pressed after
LIMITER
the polling process has been initiated
Figure 10: Elexant 5010i-LIM Front Panel with IP30 cover installed
WARNING - Do not remove the cover
while energized
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