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SPX advanced – description of parameters
SPX ADVANCED APPLICATION MANUAL
SVCH0203—October 2017 www.eaton.com
Code
ID
Description
Notes
P1.12.5.1
704
Motor thermal protection response “Motor therm prot”
Defines the response when the calculated temperature of the motor has reached
105 % (monitoring signal).
0 = No response
1 = Warning
2 = Fault, stop mode after fault according to Stop Function
3 = Fault, stop mode after fault always by coasting
P1.12.5.2
705
Motor ambient temp. factor “MotAmbTempFactor
Defines the temperature factor for conditions where the motor is located. The factor
can be set between -100.0%—100.0%.
-100.0 % = 0°C,
0.0 % = 40°C,
100.0 % = 80°C
P1.12.5.3
706
Motor cooling factor at zero speed “MTP f0 Current”
Defines the cooling factor at zero speed in relation to the point where the motor is
running at nominal speed without external cooling.
The default value is set assuming that there is no external fan cooling the motor. If an
external fan is used this parameter can be set to 90% (or even higher).
Freq. Out
Motor Nominal Freq.
100 %
Zero
cooling
Factor
70 % of Fn
Cooling Factor
The value is set as a percentage
of the motor name plate data,
(Nominal current of motor), not
the drive’s nominal output current.
The motor’s nominal current is
the current that the motor can
withstand in direct on-line use
without being overheated.
P1.12.5.5
707
Motor thermal protection: Time constant “MTP motor T”
This time can be set between 1 and 200 minutes.
This is the thermal time constant of the motor. The bigger the motor, the bigger the
time constant. The time constant is the time within which the calculated thermal stage
has reached 63% of its final value.
The motor thermal time is specific to motor design and it varies between different
motor manufacturers. The default value changes between unit sizes.
If the motor’s t6–time (t6 is the time in seconds the motor can safely operate at six
times the rated current) is known (given by the motor manufacturer) the time constant
parameter can be set basing on it. As a rule of thumb, the motor thermal time constant
in minutes equals to 2xt6. If the drive is in stop stage the time constant is internally
increased to three times the set parameter value. The cooling in the stop stage is
based on convection and the time constant is increased.
Setting this parameter does not affect the maximum output current of the drive
which is determined by parameter motor current limit alone.