Jands HP6, Technical Manual

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Disassembly 5-1
Revision 2 - 26 April, 2000 HP SERIES DIMMER TECHNICAL MANUAL
5.0 Fault Diagnosis
NOTE
Contact your authorised JANDS Distributor for repairs or servicing.
In Australia refer all repairs to an authorised JANDS service agent or return the faulty
unit in suitable packaging to:
JANDS ELECTRONICS Service Dept,
40 KENT Rd
MASCOT NSW 2020
AUSTRALIA
PHONE: +61-2-9582-0909
5.1 Protection
The HP Series dimmers feature several types of protection. These can be generally
classified as:
1. output protection,
2. thermal protection,
3. overvoltage protection.
5.1.1 Output protection
Each of the output circuits is protected by a 11.5 amp [25 amp] fast-acting magnetic
circuit breaker. These breakers are designed to pass the rated current, but will disconnect
the output circuit for any overload condition (the larger the overload, the quicker the
disconnection).
NOTE: The dimmer outlet sockets are rated at 10 [20] amps. Avoid loading the dimmer
outputs beyond the socket capacity.
The breakers protect the dimmer’s output devices from short-circuit loads and faulty
wiring looms, and save on expensive dimmer repairs. A tripped circuit breaker indicates a
load fault that requires immediate attention.
Note that the triacs in the HP12-TR will survive output short circuits under most
conditions. The more rugged SCR pairs in the HP12-SC / HP6-C will survive output
shorts under extreme conditions (high operating temperatures, high supply fault current
availability, zero cable length from dimmer to short).
5.1.2 Thermal protection
The HP dimmers feature temperature-controlled fan cooling. As the internal
temperature of the dimmer increases, the fan speed also increases. The fan begins
turning at low speed at 30
°
C, and reaches maximum speed at internal temperatures
above 50
°
C.