Danfoss Performer SH090, Application Manuallines

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43 F R CC.PC.007.B 8 .02
Application guidelines Installation
I n insta ll ations with goo d oi l ret u rn an d l ine
r u ns up to 20 m , no a dd itiona l oi l is re qu ire d. If
insta ll ation l ines e x cee d 20 m , a dd itiona l oi l ma y
be nee d e d. 1 or 2% o f the tota l s y stem re f rigerant
charge ( in weight ) can be u se d to ro u gh ly d e fi ne
the re qu ire d oi l to p-up qu antit y b u t in an y case
the oi l charge has to be a dju ste d base d on the oi l
l e v e l in the com p ressor sight g l ass .
W hen the com p ressor is r u nning u n d er stabi l i z e d
con d itions the oi l l e v e l m u st be v isib l e in the
sight g l ass .
T he p resence o f f oam fi ll ing in the sight g l ass
in d icates l arge concentration o f re f rigerant in the
oi l an d / or p resence o f l i qu i d ret u rning to the
com p ressor .
T he oi l l e v e l can a l so be checke d a f ew min u tes
a f ter the com p ressor sto p s .
W hen the com p ressor is o ff , the l e v e l in the
sight g l ass can be in fl u ence d b y the p resence o f
re f rigerant in the oi l.
Al wa y s u se origina l D an f oss POE oi l 160 S Z f rom
new cans .
T o p-up the oi l whi l e the com p ressor is i dl e . U se
the schra d er connector or an y other accessib l e
connector on the com p ressor s u ction l ine an d
a s u itab l e pu m p. See News b ull etin «Lu bricants
fi ll ing in instr u ctions f or D an f oss C ommercia l
C om p ressors ».
Oil level checking and
top-up
T he s y stem m u st be monitore d a f ter initia l start -
up f or a minim u m o f 60 min u tes to ens u re p ro p er
o p erating characteristics s u ch as :
• P ro p er metering d e v ice o p eration an d d esire d
s up erheat rea d ings
• S u ction an d d ischarge p ress u re are within
acce p tab l e l e v e l s
• C orrect oi l l e v e l in com p ressor s u m p in d icating
p ro p er oi l ret u rn
• L ow f oaming in sight g l ass an d com p ressor
s u m p tem p erat u re 10K abo v e sat u ration
tem p erat u re to show that there is no
re f rigerant migration taking pl ace
• A cce p tab l e c y c l ing rate o f com p ressors ,
inc lud ing du ration o f r u n times
• Cu rrent d raw o f in d i v i du a l com p ressors within
acce p tab l e v a lu es ( ma x o p erating c u rrent )
• No abnorma l v ibrations an d noise .
Commissioning
Insulation resistance and
dielectric strength
I ns ul ation resistance m u st be higher than 1
megohm when meas u re d with a 5 00 v o l t d irect
c u rrent megohm tester .
E ach com p ressor motor is teste d at the f actor y
with a high p otentia l v o l tage ( hi -p ot ) that
e x cee d s the UL re qu irement both in p otentia l
an d in du ration . L eakage c u rrent is l ess than 0. 5
m A.
S H scro ll com p ressors are con fi g u re d with
the pu m p assemb ly at the to p o f the she ll,
an d the motor be l ow . A s a res ul t , the motor
can be p artia lly immerse d in re f rigerant an d
oi l. T he p resence o f re f rigerant aro u n d the
motor win d ings wi ll res ul t in l ower resistance
v a lu es to gro u n d an d higher l eakage c u rrent
rea d ings . S u ch rea d ings d o not in d icate a f a ul t y
com p ressor .
I n testing ins ul ation resistance , D an f oss
recommen d s that the s y stem be fi rst o p erate d
brie fl y to d istrib u te re f rigerant thro u gho u t the
s y stem . F o ll owing this brie f o p eration , retest the
com p ressor f or ins ul ation resistance or c u rrent
l eakage .
Ne v er reset a breaker or re pl ace a fu se witho u t
fi rst checking f or a gro u n d f a ul t ( a short circ u it to
gro u n d). B e a l ert f or so u n d s o f arcing insi d e the
com p ressor .
F or the initia l charge the com p ressor m u st not
r u n an d e v ent u a l ser v ice v a lv es m u st be c l ose d.
C harge re f rigerant as c l ose as p ossib l e to the
nomina l s y stem charge be f ore starting the
com p ressor . T his initia l charging o p eration m u st
be d one in l i qu i d p hase . T he best l ocation is on
the l i qu i d l ine between the con d enser o u t l et
an d the fi l ter d rier . T hen du ring commissioning ,
when nee d e d, a com pl ement o f charge can be
d one in l i qu i d p hase : s l ow ly thrott l ing l i qu i d in
on the l ow p ress u re si d e as f ar awa y as p ossib l e
f rom the com p ressor s u ction connection whi l e
com p ressor is r u nning . T he re f rigerant charge
qu antit y m u st be s u itab l e f or both s u mmer an d
winter o p erations .
V ac uu m or charge f rom one si d e can sea l the
scro ll s an d res ul t in a non - starting com p ressor .
W hen ser v icing , a l wa y s ens u re that LP/HP
p ress u res are ba l ance d be f ore starting the
com p ressor .
B e s u re to f o ll ow a ll go v ernment reg ul ations
regar d ing re f rigerant rec l amation an d storage .
F or more d etai l e d in f ormation see " Recom -
men d e d re f rigerant s y stem charging p ractice "
news b ull etin F R CC.E N .0 5 0.
Refrigerant charging