Denon IN-Command AVR-X4000 Service Manual Download

Page: 6 / 224

SAFETY PRECAUTIONS

The following items should be checked for continued protection of the customer and the service technician.

leakage current check

Before returning the set to the customer, be sure to carry out either (1) a leakage current check or (2) a line to chassis
resistance check. If the leakage current exceeds 0.5 milliamps, or if the resistance from chassis to either side of the

power cord is less than 460 kohms, the set is defective.

Be sure to test for leakage current with the AC plug in both polarities, in addition, when the set's power is in each state
(on, off and standby mode), if applicable.

CAUTION

Please heed the following cautions and instructions during servicing and

inspection.

◎

Heed the cautions!

Cautions which are delicate in particular for servicing
are labeled on the cabinets, the parts and the chassis,
etc. Be sure to heed these cautions and the cautions
described in the handling instructions.

◎

Cautions concerning electric shock!

(1) An AC voltage is impressed on this set, so if you

touch internal metal parts when the set is energized,
you may get an electric shock. Avoid getting an

electric shock, by using an isolating transformer

and wearing gloves when servicing while the set is

energized, or by unplugging the power cord when
replacing parts, for example.

(2) There are high voltage parts inside. Handle with

extra care when the set is energized.

◎

Caution concerning disassembly and

assembly!

Through great care is taken when parts were

manufactured from sheet metal, there may be burrs on
the edges of parts. The burrs could cause injury if fingers

are moved across them in some rare cases. Wear gloves
to protect your hands.

◎

Use only designated parts!

The set's parts have specific safety properties (fire
resistance, voltage resistance, etc.). Be sure to use parts

which have the same properties for replacement. The

burrs have the same properties. In particular, for the
important safety parts that are indicated by the

mark

on schematic diagrams and parts lists, be sure to use

the designated parts.

◎

Be sure to mount parts and arrange the wires

as they were originally placed!

For safety seasons, some parts use tapes, tubes or other

insulating materials, and some parts are mounted away

from the surface of printed circuit boards. Care is also
taken with the positions of the wires by arranging them

and using clamps to keep them away from heating and

high voltage parts, so be sure to set everything back as

it was originally placed.

◎

Make a safety check after servicing!

Check that all screws, parts and wires removed or
disconnected when servicing have been put back in their

original positions, check that no serviced parts have
deteriorate the area around. Then make an insulation

check on the external metal connectors and between
the blades of the power plug, and otherwise check that

safety is ensured.

(Insulation check procedure)

Unplug the power cord from the power outlet, disconnect
the antenna, plugs, etc., and on the power. Using a 500V
insulation resistance tester, check that the insulation

resistance value between the inplug and the externally
exposed metal parts (antenna terminal, headphones
terminal, input terminal, etc.) is 1MΩ or greater. If it is
less, the set must be inspected and repaired.

Many of the electric and the structural parts used in the
set have special safety properties. In most cases these

properties are difficult to distinguish by sight, and the use
of replacement parts with higher ratings (rated power
and withstand voltage) does not necessarily guarantee
that safety performance will be preserved. Parts with
safety properties are indicated as shown below on the

wiring diagrams and the parts list in this service manual.

Be sure to replace them with the parts which have the
designated part number.

(1) Schematic diagrams

.......

Indicated by the

mark.

(2) Parts lists

.......

Indicated by the

mark.

The use of parts other than the
designated parts could cause electric

shocks, fires or other dangerous