Jands HP6, Техническое руководство

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Disassembly 5-4
Revision 2 - 26 April, 2000 HP SERIES DIMMER TECHNICAL MANUAL
5.5 Phase fault indication
The three green PHASE LEDs will light when all three power input phases are present.
WARNING
If one or more PHASE LEDs is off, IMMEDIATELY disconnect power to the
dimmer and check the mains supplies and wiring before re-connecting power to
the dimmer.
5.6 Cold lamp filaments
Cold lamp filaments consume considerably more power than warm filaments. This means
that the first time the lamp is turned on to full, the surge current can be up to ten times
greater than the rated current for the lamp.
This cold surge current may be enough to trip the output circuit breakers. If this
“nuisance-tripping” of the circuit breakers is a problem, the filament Preheat facility may
be utilised. See section 4.1.4.5 for instructions on enabling the Preheat facility.
Lamp filament resistance is roughly proportional to temperature. A filament preheated to
900
°
K (630
°
C) has a resistance about three times higher than a filament at room
temperature (300
°
K, 30
°
C).
Preheat turns on the selected channels a very small amount (around 1% at 240 volts and
4% at 110 volts) which heats the lamp filaments and increases their electrical resistance.
When the lamp is then turned on full, the surge current is much less and the circuit
breaker will not trip.
Other advantages of using Preheat are an increase in lamp life (due to the reduction of
thermal shock to the filaments), and a reduction of lamp heat up time (the lamps will
flash slightly quicker).
5.7 Memory failure
The lithium battery on the CPU card has a limited life of four to five years and will need
replacing if the dimmer starts to show signs of memory failure.
If the dimmer loses its memory, it is important that a Deep Clear (see section 4.2) be
performed when power is applied to ensure reliable operation.
CAUTION
Danger of explosion if battery is incorrectly replaced.
Replace only with the same or equivalent type
recommended by the manufacturer. Dispose of used
batteries according to the manufacturer’s instructions.