Danfoss SH090 Application Guidelines

17
FRCC.PC.007.B8.02
Application guidelines
Electrical data, connections and wiring
Winding resistance is the resistance between
phases 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 v
aries strongly with winding
temperature; if the compressor is stabilised
at a di 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 tamb
Coe cient a = 234.5
The max. operating current is the current when
the compressor operates 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.
Winding resistance
Max. operating Current
The inrush current for the Danfoss SH scroll
compressors with motor code 4 (400V /3ph /
50Hz or 460
V / 3ph / 60Hz) can be reduced using
the Danfoss digitally-controlled MCI compressor
soft starter. MCI soft starters are designed
to reduce the starting current of 3-phase AC
motors; they can reduce the inrush current by
up to 40
%, thereby eliminating the detrimental
e ects of high starting torque surges and costly
demand charges from the resultant current
spike. Upon starting, the controller gradually
increases the voltage supplied to the motor until
full-line voltage has been reached.
All settings,
such as ramp-up time (less than 0.5 sec) and
initial torque, are preset and do not require
modi cation.
Danfoss MCI
soft-start controller
When the control voltage is applied to A1 - A2,
the MCI soft starter will start the motor, according
to the settings of the ramp-up time and initial
torque adjustments. When the control voltage
is switched OFF, the motor will switch o
instantaneous
ly.
Input controlled soft start
Compressor model
Soft start reference
Ambient max. 40°C
Soft start reference
Ambient max. 55°C
SH090 MCI15C MCI15C
SH105 MCI25C MCI25C
SH120 MCI25C MCI25C
SH140MCI25C MCI25C *
SH161 MCI25C MCI25C *
SH184 MCI25C MCI25C *
S
H180 MCI50CMMCI50CM
SH240MCI50CMMCI50CM *
SH295 MCI50CM *MCI50CM *
SH300 MCI50CM *MCI50CM *
SH380 MCI50CM *MCI50CM *
SH485 NA NA
* by-pass contactor K1 is required

Danfoss SH090 Specifications

General

Brand	Danfoss
Model	SH090
Category	Air Compressor
Language	English