Electrical Phasing; Motors); Compressor Crankcase Heaters - Trane EB 036 Series Installation, Operation And Maintenance Manual

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Table Of Contents

Table of Contents

I I n n s s t t a a l l l l a a t t i i o o n n

•

VD = Line Voltage reading that deviates the farthest

from the average voltage.

Example: If the voltage readings of the supply power

measured 221, 230, and 227, the average volts would

be:

•

VD (reading farthest from average) = 221

•

The percentage of Imbalance equals:

The 2.2 percent imbalance in this example exceeds the

maximum allowable imbalance of 2.0 percent. This

much imbalance between phases can equal as much as

a 20 percent current imbalance with a resulting

increase in motor winding temperatures that will

decrease motor life.

If the voltage imbalance is over 2 percent, notify the

proper agencies to correct the voltage problem before

operating this equipment.

Electrical Phasing (Three Phase Motors)

The compressor motor(s) and the supply fan motor are

internally connected for the proper rotation when the

incoming power supply is phased as A, B, C.

Proper electrical supply phasing can be quickly

determined and corrected before starting the unit by

using an instrument such as an Associated Research

Model 45 Phase Sequence Indicator and following the

steps below:

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 ! !

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 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 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 . . V V e e r r i i f f y y t t h h a a t t n n o o

p p o o w w e e r r i i s s p p r r e e s s e e n n t t w w i i t t h h a a v v o o l l t t m m e e t t e e r r . .

1. Turn the field supplied disconnect switch that

provides power to the main power terminal block or

to the "Line" side of the optional factory mounted

disconnect switch to the "Off" position.

2. Connect the phase sequence indicator leads to the

terminal block or to the "Line" side of the optional

factory mounted disconnect switch as follows:

•

Black (phase A) to L1

•

Red (phase B) to L2

•

Yellow (phase C) to L3

3. Close the field supplied main power disconnect

switch or circuit protector switch that provides the

supply power to the unit.

W W A A R R N N I I N N G G

L L i i v v e e E E l l e e c c t t r r i i c c a a l l C C o o m m p p o o n n e e n n t t s s ! !

F F a a i i l l u u r r e e t t o o f f o o l l l l o o w w a a l l l l e e l l e e c c t t r r i i c c a a l l s s a a f f e e t t y y p p r r e e c c a a u u t t i i o o n n s s

w w h h e e n n e e x x p p o o s s e e d d t t o o l l i i v v e e e e l l e e c c t t r r i i c c a a l l c c o o m m p p o o n n e e n n t t s s 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 . .

W W h h e e n n i i t t i i s s n n e e c c e e s s s s a a r r y y t t o o w w o o r r k k w w i i t t h h l l i i v v e e e e l l e e c c t t r r i i c c a a l l

c c o o m m p p o o n n e e n n t t s s , , h h a a v v e e a a q q u u a a l l i i f f i i e e d d l l i i c c e e n n s s e e d d e e l l e e c c t t r r i i c c i i a a n n

o o r r o o t t h h e e r r i i n n d d i i v v i i d d u u a a l l w w h h o o h h a a s s b b e e e e n n p p r r o o p p e e r r l l y y t t r r a a i i n n e e d d

i i n n h h a a n n d d l l i i n n g g l l i i v v e e e e l l e e c c t t r r i i c c a a l l c c o o m m p p o o n n e e n n t t s s p p e e r r f f o o r r m m

t t h h e e s s e e t t a a s s k k s s . .

4. Observe the ABC and CBA phase indicator lights on

the face of the sequencer. The ABC indicator light

will glow if the phase is ABC. If the CBA indicator

light glows, open the disconnect switch or circuit

protection switch and reverse any two power wires.

5. Restore the main electrical power and recheck the

phasing. If the phasing is correct, open the

disconnect switch or circuit protection switch and

remove the phase sequence indicator.

Compressor Crankcase Heaters

N N O O T T I I C C E E

C C o o m m p p r r e e s s s s o o r r F F a a i i l l u u r r e e ! !

F F a a i i l l u u r r e e t t o o f f o o l l l l o o w w i i n n s s t t r r u u c c t t i i o o n n b b e e l l o o w w 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

c c o o m m p p r r e e s s s s o o r r f f a a i i l l u u r r e e . .

U U n n i i t t m m u u s s t t b b e e p p o o w w e e r r e e d d a a n n d d c c r r a a n n k k c c a a s s e e h h e e a a t t e e r r s s

e e n n e e r r g g i i z z e e d d a a t t l l e e a a s s t t 8 8 h h o o u u r r s s B B E E F F O O R R E E c c o o m m p p r r e e s s s s o o r r s s

a a r r e e s s t t a a r r t t e e d d . .

Each compressor can be equipped with a crankcase

heater. The proper operation of the crankcase heater is

important to maintain an elevated compressor oil

temperature during the "Off" cycle to reduce oil

foaming during compressor starts. Oil foaming occurs

when refrigerant condenses in the compressor and

mixes with the oil. In lower ambient conditions,

refrigerant migration to the compressor could increase.

When the compressor starts, the sudden reduction in

crankcase pressure causes the liquid refrigerant to boil

rapidly causing the oil to foam. This condition could