AE4-1322
© 2002 Copeland Corporation
Issued 4-2002
Printed in U.S.A.
17
•
For part winding start a separate capacitor should
be used for each half of the winding (50% each).
Only one capacitor is used for start delta motors
(parallel to contactor K1).
•
In the case of extreme load fluctuations (large
capacity range) combined with high demands on a
low reactive capacity, capacitors that can be
switched on and off with contactors (in combination
with a discharge throttle) may be necessary.
Design is similar to central correction.
Central correction (Fig. 22)
Central correction (Fig. 22)
Central correction (Fig. 22)
Central correction (Fig. 22)
Central correction (Fig. 22)
•
When the designing, connected loads and the
operating times of all inductive loads (including
fluorescent lamps if they do not have their own
correction) must be taken into consideration.
•
The number of capacitor stages must be selected
so that the smallest unit does not have a larger
capacity than the lowest inductive load (with P.F.
0.95). Extreme part load conditions are particularly
critical, such as can occur during the night, at
weekends or while being put into operation. If loads
are too low the entire correction device should be
disconnected from the power supply.
•
With central correction (as well as with individual
correction with contactor control) discharge throttle
must always be provided. Reconnection to the
power supply may only occur after complete
discharge and a subsequent time delay.
The layout of correction systems for motors with
direct starting is similar.
CAUTION!
CAUTION!
CAUTION!
CAUTION!
CAUTION!
It is essential to observe the general
It is essential to observe the general
It is essential to observe the general
It is essential to observe the general
It is essential to observe the general
design and layout instruction of the
design and layout instruction of the
design and layout instruction of the
design and layout instruction of the
design and layout instruction of the
correction system manufacturer
correction system manufacturer
correction system manufacturer
correction system manufacturer
correction system manufacturer.....
Frequency inverter
Frequency inverter
Frequency inverter
Frequency inverter
Frequency inverter
Operation with a frequency inverter is possible. How-
ever, layout and operating conditions must be individu-
ally approved by Copeland
.....
3.3 Compressor protection system
3.3 Compressor protection system
3.3 Compressor protection system
3.3 Compressor protection system
3.3 Compressor protection system
The SCH2/SCA2 compressors are fitted with the
protection device INT69VSY-II.
Monitoring functions
Monitoring functions
Monitoring functions
Monitoring functions
Monitoring functions
•
Winding temperature (PTC sensors in motor
winding)
- Interruption of the control current with excess
temperature
- Manual reset (after winding has cooled) by
interruption of supply voltage L/N for at least
2 seconds
•
Oil temperature (sensor with PTC resistance in oil
sump)
- Function as above (winding temperature)
Figure 20
Power factor correction on central power system
