Model 931 – Electrostatic Discharge Firing Test System


The Model 931 Firing Test System is designed specifically to determine the ESD susceptibility of pyrotechnic devices, powders and liquids. The 2-piece Electrostatic Discharge Simulator consists of a Control Unit housing all low voltage electronics and controls plus a 4½-digit LED voltage level display and a Discharge Unit containing the HVPS, polarity reversing module, plus capacitor and resistor selector modules.

The Model 931 produces discharge pulses from ±100 Volts to ±26kV. Energy is stored in capacitor banks during the charging cycle. A discharge pulse is produced when a high voltage gas filled relay disconnects the charged capacitor from its charging source and connects it to the output of the FTS Discharge Unit. The energy storage capacitor bank is installed inside the Discharge Unit. Discharge resistors are installed within the Discharge Unit or contained in individual plug-in modules depending on system configuration. R/C values must be specified at time of order. Additional capacitor and resistor modules can be plugged into the SPARE capacitor and resistor input connectors on the front panel of the Discharge Unit. Standard capacitor values range from 100pf to 0.5mf and resistor values range from 0 to 5,000 Ohms. Non-standard capacitors, resistors and voltages up to 30kV can be special ordered. A 100 Megohm resistor permanently connects the output to ground to bleed off residual voltage after a discharge plus an interlock cable connected to a user supplied switch removes power to the HVPS when the switch is open. Spring-loaded ARM and DISCHARGE switches control the charge/discharge cycle. The AUTO Mode allows for up to 9 discharges while holding down the ARM and DISCHARGE switches.

Test Standards:
Many applications require the determination of the energy threshold for ignition by electrostatic discharge of varying intensities. Energy is determined by the equation E=½CV2. Resulting data can then be used to characterize the probability of ignition due to an ESD event.

MIL-STD-1751A, (Group 1030 Test Methods) along with MIL-STDs 1512, 1576 (Method 2205) and MIL-STD-331B (Notice 3) cover the most common test standards for electrostatic discharge sensitivity testing.

  • Range: ±100 to 26,000 volts
  • Standard capacitors: 100pf to 0.5 microf
  • Standard resistors: 0, 500, 1500, 5000 ohms
  • Use for voltage and energy susceptibility testing
  • Std. HV, SPDT Charge/Discharge relay
  • Custom discharge electrodes available
  • Optional Firing Test Chamber
  • Custom R/C networks available