No.51994
V32X25EUS
V32X250EUS
V28X25EUS
4
SAFETY PRECAUTIONS
1. The d esi gn of th is pr od uct con ta in s sp ecial har d wa re , ma ny
circuit s and components specially for safety purposes. For
con ti nu ed pr ot ection , n o chan g es sh ou ld b e ma de to the o rig i nal
d esign un less a uth or ized in w ri tin g by th e ma nu fact ur er .
Rep l acemen t p ar ts must b e i d ent ic al to thos e u sed i n th e or igi n al
circu it s. S er vi ce sho uld b e p er for med by qu al if i ed p ers on nel
on ly.
2. Al te r ation s of t he desi g n or ci rcui tr y of t he pr od ucts sh ould not be
made. Any design alterations or additions will void the
m anu fact ur er 's warr a nt y and w ill f ur th er r eli eve t he ma nu factu rer
of r esp onsib ili ty for per so na l i njur y or p r op erty d am ag e r esult in g
th er efr om .
3. M an y e l ectr ical an d m ech anica l p ar ts in th e pr od ucts ha ve
special safety-related characteristics. T hese characteristics are
oft en no t e viden t f r om vi sua l insp ection n or ca n t he pr o tect io n
aff or de d by th em nece ssar ily b e ob tain ed b y u sin g r ep lacem en t
com po ne nts ra ted f or hig he r vo l tag e, w att ag e, etc. R ep lacem en t
p arts wh ic h ha ve th ese sp eci al s afet y ch ar act er ist ics ar e
identified in the parts list of Servic e manual. El ec tric al
components having su ch features are identified by shading
on the sche matic s and by (!
!!
!) on the parts list in Service
manual. The us e of a sub sti tu te r ep la cem en t w hich do es n ot
h ave th e same saf ety ch ar act er ist ics as t he r eco mmen de d
r eplac em ent par t sh ow n in th e p ar ts list of S er vice m an ual m ay
cause shock, fire, or other hazards.
4. Do n't short between the LIVE side ground and ISOL ATED
(NEUTRAL) side ground or EARTH side ground when
repairing.
Some model's power circuit is partly different in the GND. The
diff er enc e of th e G ND is sho wn b y th e LIV E : (") side GND, the
ISO LATE D( NEUTRAL) : ( #) side G ND and EARTH : ($) side
GN D. D o n't sh or t b et we en th e LIV E sid e GND an d
ISO LATE D(NEUTRAL) side GND or EARTH side GND and
n ever m ea sur e w it h a m ea suri ng a ppa ratus ( oscillo scop e etc.)
th e LI VE sid e GND an d IS OLA TED(NE UTRAL ) sid e G ND or
EARTH side GND at the s ame time.
If above note will not be kept, a fuse or any parts will be broken.
5. If any repair has been made to the chassis, it is recommended
th at t he B1 set ting shou ld b e ch ecke d or adj u ste d ( Se e
ADJUSTM ENT OF B 1 POWE R SU PPLY) .
6. The hi gh vol ta ge app lie d t o th e pi ctu r e tu be mu st con for m wit h
th at sp ecifi ed in S er vice m an ual. E xcessive h igh vo lt ag e ca n
cau se an incr e ase i n X- Ray em issi on , ar cing an d possi b le
component damage, therefore operation under excessive high
voltage conditions should be kept to a minimum, or should be
preve nt ed. If s ever e arc in g occurs, rem ove t he AC power
imm ed iate ly an d de ter mi ne th e ca use b y vi sua l i nsp ect io n
( in corr ect in stal lat ion, cr acke d or m elte d high vo lt age har n ess,
p oor so ld eri ng, et c.). To m aint ai n the p r ope r min imu m l e vel of
sof t X-R ay emi ssion, c omp on en ts i n th e high voltag e ci rcui tr y
incl ud ing t he pict ur e tu be must b e t he e xact rep lacem e nts or
alte rn at ives ap prove d b y th e ma nuf act ur er of th e c om plet e
pr od uct.
7. Do n ot c hec k high volt ag e b y drawing an arc. Use a high volt ag e
m eter or a hig h v oltag e pr ob e wi t h a V TVM. D ischa rg e th e
picture tube before attempting meter connection, by connecting
a cl ip le ad to th e gr ou nd f ra me a nd c onn ecti n g th e oth er end of
the lead through a 10kΩ2W resisto r to the an od e b utt on .
8. W hen se r vi ce i s r equ ir e d, ob ser ve th e or igi na l lea d dr ess. E xtr a
pr ec aut i on sh ou ld b e g ive n t o assur e cor r ect l ea d dress in th e
hig h voltag e cir cuit a r ea. W her e a s hor t ci rcui t h as occu rr e d,
th ose co mp on ent s tha t indica te evide nce of ove r hea ting sho uld
b e r e place d. A l wa ys u se th e ma nuf act ur er's r ep lacem en t
components.
9. Isolation Check
(Safety for Electrical Shock Hazard)
Af ter r e-ass emb lin g th e p rodu ct, al ways per f orm an i sol at io n
ch eck on the expo sed me tal p ar ts of t he cabi n et ( a nte nn a
ter m ina ls, vid eo /au dio i npu t and ou tpu t t er min als, Con tr ol kn obs,
m etal cabin et, screw he ad s, ea r ph one jack, con tr ol shaf ts, etc.)
to be su re th e p r odu ct is s af e t o o pe r ate with ou t d an ger of
elect rical shoc k.
(1) Dielectric Strength Test
The iso lati on be tw een the A C prim a ry ci rcu i t an d al l me tal p arts
exp ose d t o th e us er , p ar ticular ly an y e xp os ed met al p art h avi ng a
r etu rn p ath to t he chass is sho ul d withs tan d a volt age of 3 000 V
AC (r.m.s.) for a period of one second.
( . . . . W it hstan d a vo lt ag e of 1 10 0V A C ( r.m. s.) t o an ap pl ianc e
r ate d up to 12 0V , an d 3 00 0V AC ( r.m. s.) to an ap plian ce r at ed
200V or more, for a period of one second.)
This method of test requires a t est equipment n ot generally found
in t he servic e trad e.
(2) Leakage Current Check
Pl ug th e A C lin e c ord d ir ect l y in to th e A C ou tlet ( d o n ot use a lin e
isol ati o n transf or m er du r in g this ch eck.). U sin g a " Lea kag e
Cur r ent T este r", me asure th e l ea kag e cu rre nt f rom each exp osed
m etal p ar t of the ca bine t, p art icu l arl y any e xpos ed me tal p ar t
h aving a r e turn pa th to t he ch assis , t o a kn own go od ea rt h
gr ou nd (wa ter pi p e, e tc.) . An y leaka ge cur ren t m ust n ot e xceed
0.5mA AC (r.m.s.).
How eve r, in trop ic al ar ea , th is mu st no t exce ed 0.2 mA AC
(r.m.s.).
"
""
"Alte rnat e Che ck M et ho d
Pl ug th e A C lin e c ord d ir ect l y in to th e A C ou tlet ( d o n ot use a lin e
isol ati o n tr an sfor mer dur ing t hi s che ck.) . U se an AC vo lt me ter
h aving 1 00 0 oh ms pe r volt or m ore sens it ivity in th e fo llow ing
m ann er. Con nec t a 1 50 0Ω10W res ist or para lle le d b y a 0 .1 5µF
AC -type c apa cit or bet we en an expo sed met al pa rt a nd a kno wn
g ood e ar th gr o un d ( wa ter pipe , etc.) . M eas ur e th e A C vo lt ag e
acr oss th e res ist or w ith th e AC vo ltm eter. M ove th e resistor
con nec tion to e ach exp ose d me tal par t, p art icular ly a ny exp osed
m etal p ar t havi n g a r etu rn pat h to t he ch assi s, an d m easu re th e
AC vol tag e ac ro ss the r es ist or . N o w, re ver se th e pl u g in th e AC
ou tl et and r e pe at eac h m ea sur em en t. An y vol t ag e me asu re d
must not exc eed 0.75V AC (r.m.s.). This c orresponds to 0.5mA
AC (r.m.s.).
Howeve r, in tropica l area, this must not exceed 0.3V AC ( r.m. s.).
This corresponds to 0.2mA AC (r.m.s.).
0.15μF AC-T YPE
1500 Ω10W
GOODEARTH GROUND
PLACE THIS PROBE
ON E A CH EX PO SE D
ME T AL PA RT
ACVOLTMETER
(HAVING 1000 Ω/V,
OR MOR E SENSIT IVITY)
AV32X25EUS / AV32X250EUS / AV28X25EUS
