Hitachi RAD-18NH7A Service Manual page 93

POWER CIRCUIT
Phenomenon 1 <Rotation speed does not increase>
Is the DC voltage at least 350V?
Is the OVL lamp lit?
If the lamp is lit, it does not
indicate fault, but the unit
is overload status.
Overvoltage defect: system power
module faulty (15-times blinking)
No
Yes
– 103 –
Recheck cord, etc. of the
system power module. If
they are disconnected,
connect them securely.
If abnormality continues,
replace the system
power module.