Famco Danfoss Maneurop MT, Руководство пользователя

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Electrical data, connections and wiring
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 (fingers of similar)
• Second numeral, level of protection against water
2
protection against dripping water when tilted up to 15°
IP rating
Locked Rotor Amp value is the higher average
current as measured on mechanically blocked
compressors tested under nominal voltage. 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. A soft starter
can be applied to reduce starting current.
The MCC is the current at which the motor
protection trips under maximum load and
low voltage conditions. This MCC value is the
maximum at which the compressor can be operated in transient conditions and out of
the application envelope. Above this value,
the external electronic module will cut-out the
compressor to protect the motor.
The max. operating current is the current when
the compressors operate at maximum load
conditions and 10% below nominal voltage
(+15°C evaporating temperature and +68°C condensing temperature). 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.
MCC (Maximum
Continuous Current)
Max. Operating 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 digital ohm-meter, a ‘4 wires’ method and
measure under stabilised ambient temperature.
Winding resistance varies strongly with winding
temperature ; If the compressor is stabilised
at a different 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
coefficient a= 234.5
The compressor will only operate properly in a
single direction. Use a phase meter to establish
the phase orders and connect line phases L1, L2
and L3 to terminals T1, T2 and T3, respectively.
For three-phase compressors, the motor will run
equally well in both directions. Reverse rotation
results in excessive noise; no pressure differential
between suction and discharge; and suction line
warming rather than immediate cooling. A service technician should be present at initial
start-up to verify that supply power is properly
phased and that compressor and auxiliaries are
rotating in the correct direction.
For H series compressors, phase monitors are
required. The selected phase monitor should
lock out the compressor from operation in
reverse.
Phase sequence and
reverse rotation
protection
Motor protection
Danfoss Scroll Compressors H-Series are
equipped with an internal line break protector
mounted on the motor windings. The protector
is an automatic reset device, containing a snap
action bimetal switch.
Internal protectors respond to over-current and
overheating. They are designed to interrupt
motor current under a variety of fault conditions,
such as failure to start, running overload, and fan
failure.
If the internal overload protector trips out,
it must cool down to about 60°C to reset.
Depending on ambient temperature, this may
take up to several hours.
20
FRCC.PC.012.A7.02
GENER
AL INFORM
ATION
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STEM DESIGN
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ATION INT
O SY
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ATION
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ODUC
T INFORM
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