BESTemc

1
BESTemc
Compact Tester of Schaffner for
Conducted immunity test system
Best_emc.ppt 23.05.2001
2
BESTemc

• DimensionHeight 177.8 mmWidth 448.8
  mmDepth 590.0 mmWeight 40 kg
• DUT InputAC 80 - 260V 16A maxDC 0 -
  65V 10AConnector 16A

WARNING This instrument requires two people to
lift
2
3
DUT connection

• gt95 of all DUT connectors are 10A types with
  differentcountry specific connectors.
• The BESTemc has a16A type DUT connector.The
  user has to adapt themselves.

95 use 10Aconnectors
BESTemc
4
BESTemc control is not user-friendly

• Voltage setting Speed is 10 seconds per kV
  
• The button needs to be pressed during the entire
  time
• Setting of phase angle is too fast to stop at the
  desired phase angle
• Test time setting in Seconds, Minutes, Hours,
  Counts, or Continuous- An easy setting like
  230 Min Second is not possible

5
BESTemc Standard Routine Settings

• BESTemc offers a lot of defined Standard
  settings. The offered settings are the max.
  voltage level in both polarities for EN 50082-1/
  -2. The variation of the phase angles and some of
  the couplings must be set manually. Tests with
  Level 1 and Level4 are normally not in the menu.
• The green fields show all pre-defined
  settings of the BESTemc.

Level 4
Level 3
Level 2
Level 1
L-N, L-PE, N-PE
L, N, PE, LN, all
Air Contact
50Hz 60Hz
Tests with capacitive coupling clamp are not in
this table.
0º 90º 180 270
Burst Surge
ESD Power fail
6
Burst

• Burst frequency 1kHz...100kHz with steps of 1kHz
  max. 75 pulses / Burst2.5kHz at 4kV is not
  possible according to the data sheet.
• Continuous Burst Endless with max 75 pulses /
  Burst with 100ms Repetition time.

Continuous Mode
Constant Burst
t Burst
t Rep
BESTemc can not test with Constant Burst
7
Surge Standard Test Settings

• BESTemc standard menu offers only 12 of 88 surge
  settings. Each setting must be loaded manually.
• The WINBEST can not create the complete test by
  starting at 500V up to 4000V.

Line to PE Neutral
to PE Line to Neutral phase deg
0 90 180 270 0 90 180 270 0 90 180
270 500 V no no no no no no no no
no no no no -500 V no no no no no
no no no no no no no 1000 V no no
no no no no no no yes no no no -1000
V no no no no no no no no yes no
no no 2000 V yes no no no yes no no
no yes no no no -2000 V yes no no no
yes no no no yes no no no 4000 V yes
no no no yes no no no -4000 V yes no
no no yes no no no
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Surge Impulse Switch

• Surge switch is a mercury Relay - 35A nominal
  current, -Isolation to GND 2,650V acc. to the
  data sheet - Electrical life at 35A limited to
  250000 operations- Operating vertically - 10

Up to 4400 V
Isolation to GND 2650 V
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Surge BESTemc

• Voltage impulses over 3kV with severe wave shape
  distortions (steps)

Records of Surge impulse 4.4kV
10
Surge Impulse

• Jitter of Impulse -15 Deg- Synchronization
  setting 1Deg
• Inductance is 2.5mHacc. to IEC 61000-4-5
  inductance is 1.5mH- dU 2 x Pi x f x L x
  Inominal x 2LN - dU 50Hz 314 x 2 x 2.5mH
  x 16A 25.13V- dU 60Hz 377 x 2 x 2.5mH x
  16A 30.16V

Jitter
setting at 90 deg
Decoupling network
dU
EUT
2.5mH
11
Power Fail

• The Power Fail part is designed with relays and
  electronic devices for the DIPS and interrupts.
• The built-in relays limit the rated current of
  the BESTemc.

100
EUT
40/70
12
Power Fail

• Only 100, 70, and 40 setting is possible
  Steps of the internal autotransformer 100, 72,
  42
• Duration of a voltage interruption is 10ms...
  2.5s, minimum step 10ms- 60Hz 0.5cycle
  8.33ms is not possible
• Repetition Time 10s... 600s, Step 1s- Not
  useful for development

min 10ms
V
t
min 10s
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Power Fail

• BESTemc does not control an external motor
  variac.
• An external variac must be set manually.
• For connection, a banana plug and the DUT mains
  connector would be required.

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Power Fail (note from the manual)

• BESTemc can overheat after a certain time-
  under max load and- max repetition time ( every
  10s) - The test will stop and disconnect the
  DUT mains power supply- This is not
  indicated in the display
• As a consequencePower down of BESTemc - for
  approx. 1 hour is necessary

15
ESD

• Built-in is a NSG 435 but without display and
  switches
• Standard Test only at max. voltage levels 4kV CD
  and 8kV AD- Contact discharge 2kV levels are
  missing- Air discharge 2kV and 4kV levels are
  missing

Contact discharge 2 kV ? 4 kV Air
discharge 2 kV ? 4 kV ? 8 kV
? ?
Built-in standard ESD settings

16
Magnetic Field

• Calibration is only correct, when the calibration
  meter is in the circuit during the test
• Option INA 701 single turn coilOption INA 702
  11 turn coil

17
Pulsed Magnetic Field

• Calibration procedure is very suspect- The
  proposed shunts and clamps have normally a
  frequency range lt100kHz- A current measuring
  coil with bandwidth gt10MHz must be a Pearson
  probe or similar
• Wave shape with INA 702 is out of tolerance-
  inductance of the antenna is too high

18
Software

• Installation does not work when MS Office is open
• Coupling mode- For each coupling mode, a new
  test must be created- no automatic change of 2 /
  12 Ohm
• Polarity change within a test is not possible-
  Two different test procedures are necessary
• Report not flexible (no rtf-format capability)
• The default settings are not usefull- Burst
  1 kHz, 1 pulse/burst , Trep 2s is
  a poor default setting 5 kHz,
  75 pulses/burst , Trep 300ms is better as
  default

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Accessories

• Coupling clamp is not according to the standard
• The delivered ground plane is not according to
  the standard

20
Various

• To save the new settings of a menu, 20 seconds
  are needed.