Denon HEOS Amp HS2, Service Manual

Page: 6 / 71

SAFETY PRECAUTIONS
The following items should be checked for continued protection of the customer and the service technician.
leakage current check
Beforereturningthesettothecustomer,besuretocarryouteither(1)aleakagecurrentcheckor(2)alinetochassis
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,offandstandbymode),ifapplicable.
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) AnACvoltageisimpressedonthisset,soifyou
touch internal metal parts when the set is energized,
youmaygetanelectricshock.Avoidgettingan
electricshock,byusinganisolatingtransformer
and wearing gloves when servicing while the set is
energized,orbyunpluggingthepowercordwhen
replacing parts, for example.
(2) Therearehighvoltagepartsinside.Handlewith
extra care when the set is energized.
◎
Caution concerning disassembly and
assembly!
Through great care is taken when parts were
manufacturedfromsheetmetal,theremaybeburrson
theedgesofparts.Theburrscouldcauseinjuryiffingers
are moved across them in some rare cases. Wear gloves
toprotectyourhands.
◎
Use only designated parts!
Theset'spartshavespecificsafetyproperties(fire
resistance,voltageresistance,etc.).Besuretouseparts
which have the same properties for replacement. The
burrs have the same properties. In particular, for the
importantsafetypartsthatareindicatedbythe
z
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!
Forsafetyseasons,somepartsusetapes,tubesorother
insulatingmaterials,andsomepartsaremountedaway
from the surface of printed circuit boards. Care is also
takenwiththepositionsofthewiresbyarrangingthem
andusingclampstokeepthemawayfromheatingand
highvoltageparts,sobesuretoseteverythingbackas
itwasoriginallyplaced.
◎
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
safetyisensured.
(Insulationcheckprocedure)
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
resistancevaluebetweentheinplugandtheexternally
exposedmetalparts(antennaterminal,headphones
terminal,inputterminal,etc.)is1MΩorgreater.Ifitis
less, the set must be inspected and repaired.
Manyoftheelectricandthestructuralpartsusedinthe
sethavespecialsafetyproperties.Inmostcasesthese
propertiesaredifficulttodistinguishbysight,andtheuse
ofreplacementpartswithhigherratings(ratedpower
andwithstandvoltage)doesnotnecessarilyguarantee
thatsafetyperformancewillbepreserved.Partswith
safetypropertiesareindicatedasshownbelowonthe
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) Schematicdiagrams ....... Indicatedbythe
z
mark.
(2) Partslists ....... Indicatedbythe
z
mark.
The use of parts other than the
designated parts could cause electric
shocks,firesorotherdangerous
situations.
CAUTION Concerning important
safety parts
6