EM TEST
UCS 500 Series
Operating Manual
V 5.40
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11.7.2.
Motor variac type MV 2616
The motor variac can be used to simulate power supply failures as under-voltages, voltage interruptions and voltage
variations. The basic standard IEC 61000-4-11 and the generic standard EN 50081-2 are specifying these
phenomena.
11.7.2.1.
Voltage dips / interruptions
Voltage interruptions will cause a reduction of the power supply voltage for a certain period of time. Three different
test levels are required:
- Voltage dip by 100% to 0% of the nominal voltage for 10ms or. ½ period
- Voltage dip by 100% to 0% of the nominal voltage for 20ms respectively 1 period
- Voltage dip by 60% to 40% of the nominal voltage for 200ms respectively 10 periods
- Voltage dip by 30% to 70% of the nominal voltage for 500Ns respectively 25 periods
- Voltage dip by 20% to 80% of the nominal voltage for 5000ms respectively 250 periods
Standard voltage dips
Connection diagram MV2616
The unit has to be connected at the rear part of the equipment. For connection safety laboratory cables shall be used.
11.7.2.2.
Voltage variation
Additionally it is possible to drive certain functions of variation, which also
are required in IEC 61000-4-11. These functions can easily be
programmed within the simulators itself or within the related windows
software ISMIEC
V2 Test level [ %U1]:
40%, 0%
tf
Time for decreasing voltage [sec]
2 ± 20%
t1
Time at retained voltage [sec]
1 ± 20%
tr
Time for increasing [sec]
2 ± 20%
For new FDIS IEC 61000-4-11 (2004) use a new procedure for voltage
variation , who simulate a voltage dip during a motor start.
The motor variac will be set previously to the voltage V2. The switch to PF2
happens in the UCS 500. Then the motor variac increase the voltage
controlled by the UCS. After ti the voltage change back to PF1
The speed of the voltage variation depends on the max. speed of the
motorvariac and the control setting of the integral action controller.
The behavior can be influenced by the parameter Vnominal. Setting in the
setup menu Setup / F5 Voltage setting.
The user can optimize his setting for the test.
Vn = Vmax of motorvariac
Red curve the voltage rising is too fast.
Vn = 110% of Vnominal
Green curve optimum setting
Vn = Vnominal
Blue curve the voltage regulation is too slow.
