Ballot Details

Title Re: ESD Testing, Section 7.3 of S-112
Description From the 2012 12 20 telecom.

The following is from comment matrix rows 95, 96, and 97 suggesting a re-write of section 7.3 of S-112. Those present voted unanimously to adopt the rewrite, which follows:

7.3 ESD Test
7.31. Purpose
The purpose of this test is to evaluate the solar panel design for resistance to ESD damage, to analyze potential mission-level ESD levels for the solar array, and to establish coupon/subcoupon minimum ESD requirements based on array-level analysis.

7.3.2 Sample: Solar Cell Coupon
The coupon/subcoupon(s) for the ESD tests shall be populated with a minimum of 63 solar cells. Build the coupon/subcoupon(s) in as square a configuration as possible. A subcoupon shall have a minimum of 9 solar cells.

Part type counts for other than solar cells are determined by the requirements of Section 6.1 and the following: If the flight panels are to be equipped with blocking diodes, then representative diodes shall be wired to the circuits in flight configuration.

This test requires a coupon substrate to the requirements of Section 6.1.2.1, Flight Like Coupon/Subcoupon(s) Substrates. The count required for all part types not previously defined is to be apportioned to the total number of such parts on the flight panels taking into account flight design and reliability. However, a minimum of two such parts is required. This includes each connector type, temperature sensor type, each wire type, and so forth. In the event that test connectors are used on the flight array, two of each type are required unless the test connectors will be removed prior to flight.

7.3.3 ESD Test
Conduct the test using ISO11221 as a guide for test setups, wire routing, coupon substrate biasing and current measurement locations. Both inverted and normal gradient tests shall be performed unless an analysis of the on-orbit environment precludes either charging regime. Circuits shall be electrically biased to flight voltage and current requirements. The greatest test voltage differentials between adjacent solar cells shall simulate the greatest flight voltage differentials between adjacent solar cells.

At ATT and HTT, perform the inspection and tests required by section 6.5, Inspection and Function Test Ensemble

Expose the coupon to the appropriate charging scenarios using ISO 11221. Measure each ESD discharge and record each pulse amplitude, duration, shape, the discharge rate and the time to recharge. The duration of the test shall be based on the on-orbit environment analysis and reflect the actual time the solar array is exposed to the charging environment. During inverted gradient testing perform a simulated full panel discharge using a capacitor - resistor network to represent the charge on the panel sections not represented by the coupon.

At ATT and HTT, perform the inspection and tests required by section 6.5, Inspection and Function Test Ensemble

After completion of coupon testing, subject a sample of CICs (minimum, 20) to injected pulse current testing. The pulse shape shall be based on the shape of pulses recorded during coupon testing. The pulse amplitude and duration shall represent the peak ESD current pulse observed during coupon testing. The CICs shall be pulse injected in both forward and reverse bias, 10 repetitions each

The CICS shall be measured for electrical performance pre- and post- pulse current injection test.

Report data for each electrical test in graphical and tabular form. Summarize all visual inspections. Include test setup and coupon photographs in the report.

Section 7.3 is presently written as:
7.3 ESD Test

7.3.1 Purpose

The purpose of this test is to evaluate the solar panel design for resistance to ESD damage, to analyze potential mission-level ESD levels for the solar array, and to establish coupon/subcoupon minimum ESD requirements based on array-level analysis.

Conduct this test in accordance with the following, which takes precedence, and ISO11221 Space systems Space solar panels Spacecraft charging induced electrostatic discharge test methods.

7.3.2 Sample: Solar Cell Coupon

The coupon/subcoupon(s) for the ESD tests shall be populated with a minimum of 63 solar cells. Build the coupon/subcoupon(s) in as square a configuration as possible. A subcoupon shall have a minimum of 9 solar cells. Circuits shall be electrically biased to flight voltage requirements. The greatest test voltage differentials between adjacent solar cells shall simulate the greatest flight voltage differentials between adjacent solar cells.

Part type counts for other than solar cells are determined by the requirements of Section 6.1 and the following: If the flight panels are to be equipped with blocking diodes, then representative diodes may shall be wired to the circuits in flight configuration.

This test requires a coupon substrate to the requirements of Section 6.1.2.1, Flight Like Coupon/Subcoupon(s) Substrates. The count required for all part types not previously defined is to be apportioned to the total number of such parts on the flight panels taking into account flight design and reliability. However, a minimum of two such parts is required. This includes each connector type, temperature sensor type, each wire type, and so forth. In the event that test connectors are used on the flight array, two of each type are required unless the test connectors will be removed prior to flight.

7.3.3 ESD Test

At ATT and HTT, perform the inspection and tests required by Section 6.5, Inspection and Function Test
Ensemble.

Expose the coupon/subcoupon(s) to the predicted peak ESD current for the time period established for the array based on an analysis of the on-orbit environment.

At ATT and HTT, perform the inspection and tests required by Section 6.5, Inspection and Function Test
Ensemble.

Report data for each electrical test in graphical and tabular form. Summarize all visual inspections. Include test setup and coupon photographs in the report.
Ballot Options Ballot has closed
 [ ]  Yes
 [ ]  No
 [ ]  Abstain
Opening Date Thursday, 3 January 2013 @ 2:00 pm EST
Closing Date Wednesday, 9 January 2013 @ 12:00 pm EST
Ballot has closed.

Referenced Items

Name Type Date

ballot_542.html

  • Folder: System Ballot Results (archived)
  • Group: Solar Cells and Solar Panels CoS
  • State: Final
  • 30K

From the 2012 12 20 telecom. The following is from comment matrix rows 95, 96, and 97 suggesting a re-write of section 7.3 of S-112. Those present voted unanimously to adopt the rewrite, which follows: 7.3 ESD Test 7.31. Purpose The purpose of this test is to evaluate the solar panel design for resistance to ESD damage, to analyze potential...

page=ballotrefitems&type=document
00542: Re: ESD Testing, Section 7.3 of S-112 Document (Archive) 2013-01-09

view details View Voting Results...