FST3.1VK type compatible overfill prevention device
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Part no. 55 270 52
Connection to the controller
The controller on the road tanker or another signalling unit must be
outside the potentially
explosive area
.
The measuring circuit for the
positive temperature coefficient
(PTC) thermistor resistance is
designed as ignition protection type
intrinsically safe and may only be
connected to a certified intrinsically
safe electric circuit with the
maximum values specified here:
Nominal voltage U
i
max. 19.3V DC
Nominal current I
i
max. 150mA DC
Nominal power P
i
max. 600mW
Effective inner capacity C
i
negligible
Effective inner inductance L
i
negligible
Maximum value with no risk for
intrinsic safety U
m
max. 24V
In a fixed connection line installation, the intrinsically safe electric circuit must be kept
separate from other electric circuits. Regarding tanks designed for storing inflammable liquids,
the connection line must be inserted into the dome shaft in a gastight manner.
Since part of the intrinsically safe electric circuit is installed in zone 0, the intrinsically safe
electric circuit must be connected to the potential compensation system using the earthing
lugs of the safety barrier with the shortest possible route.
This requirement is generally fulfilled with measuring amplifiers in accordance with
the VdTÜV leaflet “Overfill prevention device 100 Part 1”.
Within the scope of testing before initial start-up and recurring tests by qualified persons in
accordance with the German Ordinance on Industrial Safety and Health (BetrSichV), the limit
indicator must be subjected to a FUNCTIONAL CHECK.
Attention is drawn to the joint requirements for a system requiring supervision according to
Section 3 of the BetrSichV for inflammable liquids. Within the scope of recurring pressure
tests on the tank, the overfill prevention device must be included in switched off mode.
Close all free connections in the feed lines of the LPG system
tightly with a suitable cap to prevent gas from flowing out.
LEAK TESTING
Risk of burning or fire
Serious burns to the skin or damage to property.
Do not use an open flame to check for leaks.
The liquefied gas unit must be checked for leaks by an expert* before the first start-up, during
checking and maintenance work, before the re-start and after important changes and repair
work. See USER QUALIFICATION!
START-UP
The product is ready for use.
The PTC thermistor probe may not be subjected to a constant current. Current
supply only during refilling by the tanker (19.3V DC, max. 24V DC)!
