AE0ZP0EC - AC-0 SSL SENSORED - User Manual
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that automatically prevent operation of the travel circuit when the operator leaves
the truck.
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Figure 4–2
One of the reason for the adoption of this Passive Emergency cell is to comply
with the EN1175-5.9.5: “A separate device independent of the speed control
device (accelerator) shall automatically prevent operation of the travel circuit
when the operator leaves the truck, e.g. seat switch, pedestrian tiller switch”. To
be sure this separate device really prevent operation of the travel circuit, it is
necessary a redundant device (together with the Elaboration Unit) reads this
separate device and stops the truck distinctly from the Elaboration Unit. This is
exactly what the Passive Emergency Cell does.
In a system with a single microprocessor technology, the weak point is that just
one unit (uC) processes the Inputs and decides alone to keep the motor moving
or not. If this elaboration unit (uC) fails it is possible it keeps the motor moving
against of the state of the commands. To avoid this risk, the Passive Emergency
cell provides a further step of safety that is a redundancy in processing the
motion request (Tiller or Seat Switch). In our controller the truck will be stopped,
releasing the tiller, disregarding if the main Elaboration Unit (uC) is right working
or not.
4.4 EMC
U
EMC and ESD performances of an electronic system are strongly
influenced by the installation. Special attention must be given to the
lengths and the paths of the electric connections and the shields. This
situation is beyond ZAPI's control. Zapi can offer assistance and
suggestions, based on its years experience, on EMC related items.
However, ZAPI declines any responsibility for non-compliance,
malfunctions and failures, if correct testing is not made. The machine
manufacturer holds the responsibility to carry out machine validation,
based on existing norms (EN12895 for industrial truck; EN50081-2 for other
applications).
EMC stands for Electromagnetic Compatibility, and it represents the studies and
the tests on the electromagnetic energy generated or received by an electrical