Performing The Power- Frequency Voltage Test - Siemens NXPLUS C Installation And Operating Instructions Manual

Preparing the test
Performing the test
Completing the check
802-9081.9 • INSTALLATION AND OPERATING INSTRUCTIONS • NXPLUS C • Revision 11
18.5

Performing the power- frequency voltage test

If required, a test with rated short-duration power-frequency withstand voltage can be
performed on site. The busbar voltage transformers are designed for a repeat test at 80% U
and 50 Hz according to IEC 62271-200.
At the factory, the individual feeders are routine-tested by means of a rated short-duration
power-frequency voltage test.
As a rule, the test with these high power-frequency voltage test levels is performed before
connecting the cables. If the cables are already connected, power-frequency voltage test
equipment with a very high rating is necessary, and the permissible test voltage of the
connected cables would be exceeded.
For detailed information about cable tests, see page 266, "Cable testing".
Voltage indicators may be damaged by test voltage during cable tests.
May cause property damage.
➭ Short-circuit the voltage indicators with short-circuit plugs at the earthing points of the test
sockets.
Fig. 149: Short-circuit plug, make Kries,
order number 2500029
➭ Switch the circuit-breaker and the three-position switch of the incoming feeder to CLOSED
position to perform the power-frequency voltage test.
➭ Switch all other three-position switches to EARTHED position.
➭ Earth the voltage transformers at the feeder via the voltage transformer disconnector.
➭ If applicable, remove the surge arresters from the busbar and the incoming feeder.
➭ Cover the coupling units of the surge arresters with surge-proof caps.
➭ Apply the power-frequency test voltage in a surge-proof way at the cable connection
bushing via test adapters.
✔ Now you can carry out the test.
➭ Earth adjacent phases.
➭ Test phases L1, L2 and L3 consecutively for 60 seconds with the rated short-duration power-
frequency voltage.
➭ Switch the voltage transformer disconnector to CLOSED position.
➭ Mount the surge arresters.
NOTICE
Fig. 150: Short-circuit plug, make
Horstmann, order number
51-9904-001
Installation
D
183/293