Fault Diagnosis
5-0
Revision 2 - 20 March, 1997
HP SERIES DIMMER
OPERATING 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 Pty Ltd
Service Department
40 Kent Rd
MASCOT NSW 2020
Phone +61-2-9582-0909
Fax
+61-2-9582-0999
5.1
Protection
The HP12-TR / HP12-SC dimmers feature several types of protection. These can be
generally classified as:
•
Output protection
•
Thermal protection
•
Over and Under voltage protection
5.1.1
Output protection
Each of the twelve output circuits is protected by a 11.5 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: 3-pin GPO outlet sockets are rated at 10 amps. Dimmer channels should
not be loaded 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 will survive output shorts
under extreme conditions (high operating temperatures, high supply fault current
availability, short cable length from dimmer to fault).
