PROEL HP-X series, Service Manual

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9 HPX1200 Malfunction Analysis on SMPS.
9.1 Circuit Diagram of SMPS
9.2 HPX1200 Malfunction Analysis on SMPS:
Sequence
No.
Circuit
Function
Failure
1
Line Filter and
the Soft ‐ start
‐ The AC fuse on the rear panel was burnt when connected the
electricity: check the RT1 varistor device and the other line filter
device to see if there is short circuit.
‐ RL1 Relay does not pull ‐ in and the thermistor NPTR1 is burnt so the
amplifier can not start.
‐ Connecting the jumper of 110V and ACI port, the double voltage
rectifier will let the circuit work with 110V and 120V mains voltage.
2
LLC resonant
converter
‐ 85°c temperature control switch is often closed result to the
start ‐ up unavailable;
‐ If start ‐ up the equipment, high ‐ current will results to the burnt out
of the DC/300V fuse;
3
Fan Speed
Control
Circuit
‐ Fans do not work.
‐ Fast rotating.
‐ It is easily to go into over ‐ heat protection if the fans don’t speed
up after the module temperature increasing.
4
Rectifier
Output
‐ Power protection caused by the damage of high ‐ speed diodes
(D13, D14, D15, D16, E11, E12, C27, C261, C271) or any of rectifier
filter device.
‐ Power amplifier start ‐ up protection.
‐ Power amplifier protection caused by no ± 15V output; all the
indicator on the panel do not shined because no +24V output
(start ‐ up unavailable)
Repairing Guide:
1) When repairing the SMPS board, please cut the DC/300V fuse, series connect a 100W—200W
lamp to start the machine, preventing the damage of related device when repairing.
2) When the SMPS can not be started, repeats the protection and restart, please disconnect +