Sony LMT-300, Service Manual

Page: 51 / 92

3-5 (E)
LMT-300
3-4. Replacing the Main Parts
3-4-1. Switching Regulator
If an abnormal state occurs in the switching regulator, it is noti fi ed by the ALARM indicator (D112) on
the DP-455 board (amber: blinks, red: lights up). Replace the switching regulator whose POWER indica-
tor blinks or lights up (red). (Refer to Section 1-4-2.)
Replacement part
Part name: Switching regulator
Part number:
!
1-474-334-11
Replacement procedure
m .
For your safety, be sure to turn off the power before replacing the power supply.
.
When supplying the power, block the power slot with the power source or the panel to
prevent the decrease of cooling effect.
.
The switching regulator installed in this unit differs from the shipment time.
Old type: A-1795-659-A
New type: 1-474-334-11
.
When installing the two switching regulators, be unmixed with the old one and new one. If
mixed, this unit may operate improperly.
1. Turn off the power of the switching regulator to be
replaced and unplug the power cord from the AC inlet.
2. Remove the two screws and pull out the switching
regulator in the direction of the arrow while holding
the handle.
3. To install, reverse the removal procedure.
m
.
Push the handle of the switching regulator to secure-
ly attach it.
.
Tighten the fi xing screws securely to the switching
regulator.
.
If the switching regulator is not attached securely,
the contact resistance of the connector increases,
which may result in a
fi re or damage to the parts.
m
.
The switching regulator can be replaced in the state that
it is installed in SRX-R320.
.
At the factory, this unit has one switching regulator.
However, it is possible to mount another switching regu-
lator to this unit using the slot of the spare power supply.
When the two switching regulators are mounted on this
unit, even if the power of one switching regulator is
turned off, this unit can operate if the power of the other
switching regulator is turned on.
Switching regulator
Power switch
B3
x
6
Handle