PrimaLuna EvoLution Series - Fuse Protection and Electronic Safeguards

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EvoLution#Series#
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Fuse%Protection%
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Warning!#Fuses#are#safety#valves.#They#should#always#be#replaced#with#the#exact#same#value#and#type.##
Never#attempt#to#check#or#replace#a#fuse#while#the#amp#is#plugged#in.#Turn#it#off#and#unplug#the#AC#cord#
before#continuing.#Wait#10#minutes#to#let#tubes#cool#down#and#the#circuit#to#fully#discharge.#
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Mains#Fuse:%The#mains#fuse#is#located#on#the#rear#of#the#amplifier,#just#
below#the#power#cord#socket#(see#picture#on#the#left).#T he #fuse #ratin g#is#1 #x#
Littelfuse#213#Series#3.15A#Slow#Blow# 5#x#20mm#fuse#for#100M125VAC#and#
Littelfuse#213#Series#1.6A#Slow#Blow#5#x#20mm#fuse#for#200M250VAC.#
Always#replace#with#the#same#type#and#value#fuse!#The#fuse#holder#can#be#
opened#using#a#small#slotted#flat#blade#screwdriver.##
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The#IEC#connector#is#mounted#with#2#different#color#screws.#One#silver,#o n e #
black.#The#silver#screw#indicates#the#Live#AC#in#the#IEC#connector.#It#helps#with#the#"correct" #co n n e c tio n #
to#AC.#Nevertheless#always#check#the#AC#cable#by#measuring#as#not#every#AC#cable#is#const ru c te d#the#
same#way.#
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The#Adaptive#Auto#Bias#Board#is#protected#with#an#easily#accessible#Littelfuse#
213#315mA#fuse#located#next#to#the#on#/#off#power#switch#on#the#left#side#of#the#
Amplifier,#just#behind#the#front.#
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Electronic#Protection%
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The#PrimaLuna#EVO#Tube#Integrated#Amplifiers#are#equipped#with#Soft#Start™#and#come#with#an#
extensive#output#stage#protection#circuitry#with#+B#relay#to#protect#output#transformers,#resistors#and#high#
voltage#power#supply#in#case#a#tube#fails.##
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The#board#also#comes#with#a#BTI™#circuit.#BTI™#stands#for#Bad#Tube#Indication#(by#the#change#of#front#
LED#to#red),#making#tubeMlife#again#a #b it#easier.#The#BTI™#circuit#is#totally#inactive#during#normal#
operation.#However#when #on e#(o r#m ore )#ou tpu t#tub e(s )#dra w (s )#s ign ificantly#more#curren t#tha n#n orm a l#for#
a#couple#of#seconds,#such#as#when#a#loudspeaker#terminal#shortMcircuits#with#volume#turned#up,#or#in#the#
case#of#an#output#tube#failure,#the#BTI™#circuit#“reads”#the#changes#as#a#potential#threat#and#as#a#
protective#measure,#interrupts#the#power#supply.#It#indica te s ,#b y #th e #led #in#fron t#o f#t h e #p o wer#tub e , #w hich#
tube#m ig h t#b e #b a d .#To#reset,#simply#turn#the#power#off#and#afte r#two #m inu tes ,#turn#b ac k#on .#However,#
you#do#not#want#to#repower#the#unit#until#the#cause#of#the#failure#has#been#identified#and#resolved.#
Switching#the#power#back#on#too#early# also#can#fool#the#BTI#circuit#into#acting#as#though#the#problem#has#
not#been#totally#resolved#and#it#ma y#p ut#the #amp#back#in to#pro tec tion#mode#ag ain.#S o #be#s ure #to#g ive#it#
enough#time#to#reset!#