FRCC.PC.017.A1.02
10
A
PPLICATION
GUIDELINES
The compressor terminal box IP rating according to CEI 529 is
IP22
for all models. IP ratings is only valid
when correctly sized cable glands of the IP rating is applied.
• First numeral, level of protection against contact and foreign objects
2
protection against object size over 12.5 mm (fi ngers of similar)
• Second numeral, level of protection against water
2
protection against dripping water when tilted up to 15°
IP rating
E
LECTRICAL
DATA
,
CONNECTIONS
AND
WIRING
LRA is the higher average current as measured
on a mechanically blocked compressor tested
under nominal voltage. LRA is printed on the
nameplate.
The LRA value can be used as a rough estimation
for the starting current. However in most cases,
the real starting current will be lower. Many coun-
tries have defi ned limits for the starting current
in domestic use. A soft starter can be applied to
reduce starting current.
The MCC is the current at which the internal mo-
tor protection trips under maximum load and low
voltage conditions.
This MCC value is the maximum at which the com-
pressor can be operated in transient conditions
and out of the application envelope. Above this
value the overload will switch off to protect the
motor.
MCC (Maximum
Continuous Current)
LRA (Locked Rotor Amp)
Winding resistance
Winding resistance is the resistance between
indicated terminal pins at 25°C (resistance value
+/- 7%).
Winding resistance is generally low and it requires
adapted tools for precise measurement. Use a dig-
ital ohm-meter, a ‘4 wires’ method and measure
under stabilised ambient temperature. Winding
resistance varies strongly with winding tempera-
ture ; If the compressor is stabilised at a diff erent
value than 25°C, the measured resistance must be
corrected with following formula:
a + t
amb
R
tamb
= R
25°C
a + t
25°C
t
25°C
: reference temperature = 25°C
t
amb
: temperature during measurement (°C)
R
25°C
: winding resistance at 25°C
R
amb
: winding resistance at t
amb
coeffi
cient a= 234.5
The Performer® Heat Pump scroll compressors
are designed to operate without any assistance if
running within the defi ned nominal voltage. PSC
wiring is suffi
cient (see below).
Electrical connections
The start winding (C-S) of the motor remains in cir-
cuit through a permanent (run) capacitor.
This permanent (run) capacitor is connected
between the start winding (C-S) and the run win-
ding (C-R).
PSC wiring
The Max Oper. A is the current when the compres-
sor operates at maximum load conditions and
10% below nominal voltage.
This value which is the max rated load current for
the compressor is new on the nameplate.
Max Oper. A can be used to select cables and
contactors.
In normal operation, the compressor current
consumption is always less than the Max Oper. A
value.
Max Oper. A (Maximum
Operating Amp)
C
S
R
Line
Run
Capacitor
