Power Factor Correction Capacitors; (Optional) - Trane CenTraVac CDHF Series Installation, Operation And Maintenance Manual

Power Factor Correction
Capacitors (Optional)
Power factor correction capacitors (PFCCs) are
designed to provide power factor correction for the
compressor motor. PFCCs are available as an option
for unit- and remote-mounted starters.
N N o o t t e e s s : :
• Verify PFCC voltage rating is greater than or
equal to the compressor voltage rating
stamped on the unit nameplate.
• Refer to the wiring diagrams that shipped
with the unit for specific PFCC wiring
information.
N N O O T T I I C C E E
M M o o t t o o r r D D a a m m a a g g e e ! !
F F a a i i l l u u r r e e t t o o w w i i r r e e P P F F C C C C s s i i n n t t o o t t h h e e s s t t a a r r t t e e r r c c o o r r r r e e c c t t l l y y
c c o o u u l l d d c c a a u u s s e e m m i i s s a a p p p p l l i i c c a a t t i i o o n n o o f f t t h h e e s s e e c c a a p p a a c c i i t t o o r r s s
a a n n d d r r e e s s u u l l t t i i n n a a l l o o s s s s o o f f m m o o t t o o r r o o v v e e r r l l o o a a d d p p r r o o t t e e c c t t i i o o n n
a a n n d d s s u u b b s s e e q q u u e e n n t t l l y y c c a a u u s s e e m m o o t t o o r r d d a a m m a a g g e e . .
P P F F C C C C s s m m u u s s t t b b e e w w i i r r e e d d o o n n e e o o f f t t w w o o w w a a y y s s a a s s s s h h o o w w n n a a s s
e e x x p p l l a a i i n n e e d d i i n n t t h h e e f f o o l l l l o o w w i i n n g g f f i i g g u u r r e e s s a a n n d d
a a c c c c o o m m p p a a n n y y i i n n g g t t e e x x t t ( ( O O p p t t i i o o n n 1 1 a a n n d d O O p p t t i i o o n n 2 2 ) ) . .
Figure 40. Option 1—PFCCs installed downstream of
starter contactor, upstream of current transformers
Motor Starter
Contactor
1
Power
2
Circuit
3
Fused
Disconnect
or Suitable
Breaker
Enclosed
3-phase
Capacitor
CDHF-SVX01N-EN
Current
Transformer
Motor
Fuses
Unit
W W A A R R N N I I N N G G
H H a a z z a a r r d d o o u u s s V V o o l l t t a a g g e e w w / / C C a a p p a a c c i i t t o o r r s s ! !
F F a a i i l l u u r r e e t t o o d d i i s s c c o o n n n n e e c c t t p p o o w w e e r r a a n n d d d d i i s s c c h h a a r r g g e e
c c a a p p a a c c i i t t o o r r s s b b e e f f o o r r e e s s e e r r v v i i c c i i n n g g c c o o u u l l d d r r e e s s u u l l t t i i n n d d e e a a t t h h o o r r
s s e e r r i i o o u u s s i i n n j j u u r r y y . .
D D i i s s c c o o n n n n e e c c t t a a l l l l e e l l e e c c t t r r i i c c p p o o w w e e r r , , i i n n c c l l u u d d i i n n g g r r e e m m o o t t e e
d d i i s s c c o o n n n n e e c c t t s s a a n n d d d d i i s s c c h h a a r r g g e e a a l l l l m m o o t t o o r r s s t t a a r r t t / / r r u u n n
c c a a p p a a c c i i t t o o r r s s b b e e f f o o r r e e s s e e r r v v i i c c i i n n g g . . F F o o l l l l o o w w p p r r o o p p e e r r
l l o o c c k k o o u u t t / / t t a a g g o o u u t t p p r r o o c c e e d d u u r r e e s s t t o o e e n n s s u u r r e e t t h h e e p p o o w w e e r r
c c a a n n n n o o t t b b e e i i n n a a d d v v e e r r t t e e n n t t l l y y e e n n e e r r g g i i z z e e d d . . F F o o r r v v a a r r i i a a b b l l e e
f f r r e e q q u u e e n n c c y y d d r r i i v v e e s s o o r r o o t t h h e e r r e e n n e e r r g g y y s s t t o o r r i i n n g g
c c o o m m p p o o n n e e n n t t s s p p r r o o v v i i d d e e d d b b y y T T r r a a n n e e o o r r o o t t h h e e r r s s , , r r e e f f e e r r t t o o
t t h h e e a a p p p p r r o o p p r r i i a a t t e e m m a a n n u u f f a a c c t t u u r r e e r r ' ' s s l l i i t t e e r r a a t t u u r r e e f f o o r r
a a l l l l o o w w a a b b l l e e w w a a i i t t i i n n g g p p e e r r i i o o d d s s f f o o r r d d i i s s c c h h a a r r g g e e o o f f
c c a a p p a a c c i i t t o o r r s s . . V V e e r r i i f f y y w w i i t t h h a a C C A A T T I I I I I I o o r r I I V V v v o o l l t t m m e e t t e e r r
r r a a t t e e d d p p e e r r N N F F P P A A 7 7 0 0 E E t t h h a a t t a a l l l l c c a a p p a a c c i i t t o o r r s s h h a a v v e e
d d i i s s c c h h a a r r g g e e d d . .
F F o o r r a a d d d d i i t t i i o o n n a a l l i i n n f f o o r r m m a a t t i i o o n n r r e e g g a a r r d d i i n n g g t t h h e e s s a a f f e e
d d i i s s c c h h a a r r g g e e o o f f c c a a p p a a c c i i t t o o r r s s , , s s e e e e P P R R O O D D - - S S V V B B 0 0 6 6 * * - - E E N N . .
Simultaneously disconnect capacitors and load from
line power. If the capacitors are not switched offline
when the load is disconnected, they continue to add
capacitance to the electrical distribution system. A
leading power factor—too much capacitance—may
eventually develop. This overprotection causes poor
voltage regulation (i.e., voltage is high when the circuit
is unloaded, then drops as loads are added).
Figure 41. Option 2—PFCC wires routed through
current transformers
Fused
Disconnect
or Suitable
Breaker
Transformer
1
Power
2
Circuit
3
Enclosed
3-phase
Capacitor
Unit
Size motor overload protection to account for
capacitor-supplied current. Overloads are typically set
to measure the total current drawn by the motor. When
PFCCs are used, they become the source of part of that
current. If the current they provide is not registered by
the overload protectors, potentially damaging
amperage can reach the motor. The simplest way to
ensure that the overloads detect all current supplied to
the motor is to position the PFCCs upstream of the
current transformers as shown in the preceding figure
(Option 1). If the capacitor connection points are
downstream of the current transformers, route the
PFCC leads through the current transformers as shown
P P o o w w e e r r S S u u p p p p l l y y W W i i r r i i n n g g
Current
Motor
Motor Starter
Contactor
Fuses
57