Schulz Control I Manual De Instrucciones página 216

Motor protections are part of the advanced interface monitoring, applied in two ways. First, the frequency and phase protections are
promoted through connection X12 (L1, L2 and L3) - menus P16 and P17 for detailed information. Next, there are protections for phase
angle, low current detection, blocked rotor, overload and phase imbalance - menu P14 for detailed information.
P14.01
P14.02
P14.03
Motor Protection
P14.04
P14.05
P14.06
P14.07
P14.08
Press ENTER to access the sub-menus
Reading and editing with keyboard or ECO card
Parameterizing the motor's rated current:
For motor protection to function correctly, it is important to set the rated current of the main motor in parameter P14.03 and also the rated fan
current in parameter P14.07.
The nominal current can be obtained from the motor nameplate (rated current * service factor). If this value is not available, the current can be
calculated as follows:
Where, Im is the motor current, P(W) is the rated power of the motor in Watts, FS is the motor service factor, V
the motor power factor (cosФ) and ɳ the motor efficiency.
E.g.: For a main motor of 37kW, service factor 1.1, line voltage 380V, power factor 0.85 and yield of 89%:
Note: The same formula can be used to calculate the fan motor current.
Selection of current transformer (CT) and measurement positioning:
CT Selection: There is a wide range of current transformers on the market, for example, from 5A to 650A. To avoid reading errors, the measu-
red current must correspond to at least 40% of the rated CT current.
Loop the CT with more turns when necessary, considering that the measurement will be multiplied by this factor (e.g. 3 turns → measured
current * 3).
Note: when the TC is looped with more turns (>1) be sure to set parameter P19.
Main motor:
Pay attention to the current measuring point. The "delta" current is 1.73 times smaller than the "star" current. The current parameter on the
interface should be adjusted to suit the measured value. In the case of the previous example, if the current to be adjusted at the interface is
measured in "delta" it must be 82A/1.73=47A.
Press 'ENTER'. Use the 'UP' and 'DOWN' arrows to set between ON and OFF. Press 'ENTER'. The set value is stored in
Main MTR protection
memory and the browser returns to P14.01.
Main motor rated current. Press 'ENTER'. Use the 'UP' and 'DOWN' arrows to set between 5.0A and 1000A (pitch 0.1A).
Protec MTR fan
Press 'ENTER'. The set value is stored in memory and the browser returns to P14.03.
Main motor rated current. Press 'ENTER'. Use the 'UP' and 'DOWN' arrows to set between 5.0A and 1000A (pitch 0.1A).
MTR Main Rated Curr
Press 'ENTER'. The set value is stored in memory and the browser returns to P14.03.
Time factor for the star/delta transition (see example at the end of this chapter). Press 'ENTER'. Use the 'UP' and 'DOWN'
Main MTR Start arrows to set up between 1.1 and 3.0 (pitch 0.1). Press 'ENTER'. The set value is stored in memory and the browser returns
to P14.04.
Blocked rotor current factor of the main motor (see example at the end of this chapter). Press 'ENTER'. Use the 'UP' and
ROT BLOC main MTR 'DOWN' arrows to set between OFF and 5.0 (pitch 0.1). Press 'ENTER'. The set value is stored in memory and the browser
returns to P14.05.
Main motor phase unbalance factor (see example at the end of this chapter). Press 'ENTER'. Use the 'UP' and 'DOWN'
DES phase main MTR
arrows to set between 5% and 40%. Press 'ENTER'. The set value is stored in memory and the browser returns to P14.06.
Fan motor rated current. Press 'ENTER'. Use the 'UP' and 'DOWN' arrows to set between 0.5A and 100A (pitch 0.01A).
Fan MTR Rated Curr
Press 'ENTER'. The set value is stored in memory and the browser returns to P14.07.
Fan motor start time (during this time the current overload is disabled). Press 'ENTER'. Use the 'UP' and 'DOWN' arrows to
Start Fan MTR
set between 1s and 10s (pitch 0.1s). Press 'ENTER'. The set value is stored in memory and the browser returns to P14.08.
216
is the motor line voltage, FP is
L