Franklin Q-link - Page 97

97
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Fault Cause
 Remedy
VFDShortCircuit(C) AVFD shortcircuitfault 
occurswhenthereisan
internalorexternalshort
circuitontheVFDoutput 
circuit.Thisisan
instantaneousfault.

 Checkifpowerlinewiringis
connectedtoVFDmotorterminals
 Checkthattherearenoshorts
visibleontheoutputcircuitofthe
VFD
 Disconnectthemotorwiresatthe
VFD,disablethenomotor
protectioninPROTEC
TION‐03,and
runtheVFDwithnoload.Ifproblem
persists,thentheVFDoutputis
shortedinternally.Consider
replacingtheVFDanddon’tforget
tocheckthemotorcircuitalsofor
shorts.Thismayhavecau
sedthe
damageandcouldpossiblydamage
anewlyinstalledVFDifnot
corrected.
 Checkthattherearenoshortsinthe
wiresrunningbetween yourVFD
andthemotor
OverVoltage(L) AVFD overvoltagefault
occurswhentheVFD’s
internalDCbusvoltagelimit
isexceeded.Thisisan
instantaneousfault.
 Checkthatthemeasuredline
voltagematchestheVFDrated
voltage
 CheckthattheDECtimeis
adequatelyhightoallowforslow
ramp‐downofthemotorload
.
Deceleratingtooquicklycancreate
harmfulregenerativevoltage.
 Forfansandotherhigh‐inertia
applications,it’sbesttousethe
“coast”stoppingmodeselectablein
PRIMARY‐30toallowforgradual
motorslowing
 Forveryhigh‐inertialoads,consider
installingadynamicbrakingunitand
brakingresistortoabsorbany
excessregenerativevoltage
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