EM TEST
UCS 500 Series
Operating Manual
V 5.40
70 / 99
11.5. The Power Fail Test
The generator type UCS 500N5/N7 simulates the following interference :
- Voltage dips
- Voltage interruptions
- Voltage variations
- Inverse
11.5.1.
Voltage Interruptions
Depending on the preselected test parameters at the front panel of the simulator the power supply for the EUT is
interrupted for a certain time and at a certain phase angle (AC power supplies).
The power supply for the EUT is connected at the rear part of the
simulator to channel PF1.
The power supply may be taken directly from the mains power
supply or from a separate voltage source. Mostly used for this
tests are motor driven variacs
Power fail tests are normally carried out at a nominal voltage and
at maximum tolerance under-voltage.
The nominal voltage may be connected to PF1 and the reduced
dip voltage to PF2.
The power fail test may be carried out in various operating modes:
High impedance interruptions
With
U
mode the EUT supply is interrupted by the electronic
switch. The PF2 input is not connected. The EUT must discharge
itself internally.
Low impedance interruptions
The EUT supply is connected to PF1. The channel PF2 is short-
circuited (L-N). The EUT supply is disconnected by the electronic
switch of PF1 and the EUT will be discharged into a low
impedance via the electronic switch of PF2
