Raytec PULSESTAR VTR4, Руководство по установке

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6.1
Power supply
Refer to the information in Section 2, Safety (or Section 3, Sicherheit, or Section
4, Sécurité) concerning power supply arrangements for the VTR4. Choose a PSU
that limits its output current by design, by setting the current limit on the supply
(if this feature exists) or use fuses. Remember to derate the fuse, if mounted in
an enclosure, as the temperature will be higher than ambient. The external
power supply needs to be able to supply at least 5.0A.
The use of a regulated power supply with 100% short circuit protection is
recommended. If, however a non-regulated power supply is used, then the
maximum ripple voltage of this power supply must not exceed 10% of the actual
DC value.
The low voltage and AC mains wiring should be routed separately. If they must
be loomed together ensure that low voltage insulation rating is sufficient or
that supplementary insulation is used.
The maximum recommended power supply cable length 3m. If longer cables
are fitted, or if surge or transient interference greater than +/-60V may occur
on the power supply lines, additional surge protection should be provided.
6.1.1
Power-up surges
The VTR4 will draw current surges from the user’s power supply at various stages
as it becomes operational. At the instant on which power is applied, the
capacitors internal to the VTR4 will draw a surge that is dependent upon the
impedance of
the user’s power supply and cabling. If not limited, this surge will
be of the order of 100-150Amps with a duration of approximately 50µs.
After a few seconds, the internal micro-controller will begin to apply power to
the LEDs. This will cause an initial demand for current, followed by regular
bursts as shown below.