Download Space engineering Electromagnetic compatibility

ECSS-E-20-07A Draft
4 April 2008
c.
Connect the high-voltage electrode to the discharge circuit at the node between the
spark gap and the capacitor.
d.
The discharge circuit length is not larger than what is necessary to place in series the
20 cm long coupling wire, the damping resistor, the discharge capacitor, the spark
gap and the current probe.
NOTE
e.
For calibration the test equipment is configured as shown Figure 5-30, and meeting
following provisions:
1.
the discharge circuit is not coupled to the EUT,
2.
choke resistors are near the capacitor,
3.
the current probe monitoring the primary current from the ESD source is near
the damping resistor, at the capacitor side,
4.
the high voltage probe is measuring the voltage across the capacitor,
grounded at the damping resistor side.
NOTE
f.
It is important to ensure that the discharge loop is as small
as possible for achieving the transient pulse duration
objective defined in 5.5.12.4.5.5.12.4b.4.
The high-voltage probe is not meant to measure the voltage
during the discharge but the voltage reached before
discharge
Test the EUT by configuring the test equipment as specified in Figure 5-31 and
meeting the following provisions:
1.
the high voltage probe used for calibration is removed,
2.
the EUT is mounted on a conductive ground plane using the space vehicle
mount and attach points, and operated using the actual electrical harness, or
an EMC test harness of identical construction to the actual harness.
NOTE
It is preferable to use the actual electrical harness.
3.
the discharge circuit is supported 5 cm above the ground plane by a nonconductive standoff with high-voltage insulation capability,
4.
from calibration, the discharge circuit is kept unchanged in size and shape,
and tightly electromagnetically coupled 20 cm along an EUT bundle, held by
dielectric bonds
NOTE
a maximum separation distance of 1 cm between the
injection wire and the outer circumference of the bundle
under test is a condition for achieving a tight
electromagnetic coupling
5.
a current probe is monitoring the primary current from the ESD source near
the damping resistor,
6.
a current probe is monitoring the current in the EUT harness, 5 cm from the
EUT connector.
5.5.12.4
Procedure
The test procedures shall be as follows:
a.
Turn on the measurement equipment and wait until it is stabilized
b.
Perform a calibration using the calibration setup:
1.
Select the spark gap device or adjust the spark length at the voltage
breakdown to be used for the test
2.
Turn on the high voltage generator
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