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Details, datasheet, quote on part number:GP-486
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Datasheet text preview:
P
erkinElmer's Mini-Triggered
Mini-Triggered Spark Gaps and Transformers
EVERYTHING IN A NEW LIGHT.
Spark Gaps are designed for high reliability switching up to 4 kV and 10 kA. Constructed of hermetically sealed ceramic-metal, filled with pressurized gas, they are typically used for activating electro-explosive devices such as exploding bridgewires, electronic safe and arm systems, and detonators. PerkinElmer's Trigger Transformers are matched to the requirements of the Mini-Triggered Spark Gaps to provide a high voltage pulse with a fast rise time and low current. PerkinElmer Trigger Transformers are designed to be the most durable and reliable transformers available.
Features · High reliability · Extremely low jitter · Environmentally durable · Small size · Matching trigger transformers
PerkinElmer Optoelectronics
page 3
Miniature Triggered Spark Gaps
The triggered spark gap is a three element, gas-filled, ceramic-to-metal, hermetically sealed, pressurized switch that operates in an arc discharge mode, conducting moderately high peak currents for short durations. Commutation between two main electrodes is initiated by a trigger pulse.
These compact small, rugged gaps were designed for high-reliability applications where size, switch speed, and ability to withstand rugged missile environmental conditions of extreme shock, temperature, and vibration are required. They are designed for switching peak currents up to 10kA at operating voltages from 2.0 to 4.0 kV with reliable triggering voltage of 2kV. Prefires and failure to fire have been fully evaluated in the basic gap designs.
Performance Characteristics
Electrical characteristics are determined by testing in the circuit shown in Figure 1. The output circuit consisting of the switch, a 0.2 µF capacitor, and a 0.25 ohm current viewing resistor (CVR) is typical for life testing. It closely matches the conditions found in many typically used circuits. For function testing, the 0.25 ohm CVR is replaced with a 0.005 ohm CVR. Typical data taken with a 0.005 ohm CVR are shown in Figure 2. This curve contains traces of the trigger voltage and conduction current. First, the trigger voltage rises to the point of trigger breakdown. Then there is a period designated "turn-on" or delay time during which the arc is forming followed by main gap conduction. This delay time varies from 50 to 1500 ns depending on gap operating voltage, trigger mode, amplitude and pulse width.
Applications
Precision timing and firing for in-flight functions such as rocket motor ignition, warhead detonation and missile stage separation. Each of these applications involves the activation of electro-explosive devices such as:
Switching speeds of 70ns with trigger pulse energies as low as 500 microjoules is typical.
Conduction Current
· · · ·
Exploding bridgewire (EBW) Exploding foil initiator (EFI) Electronic safe and arm (ESA) Slapper/detonator
Trigger Voltage Time Turn-on Time
Figure 2. Trigger Voltage Breakdown and Main Gap Conduction Current
5 m OE GAP + VT(IN) TR 2N6798 1.0 m CT AE + T 0.2 µF
+
VT(OC)--TRIGGER VOLTAGE (OPEN CIRCUIT)
2.4-3.5 KV
NORMAL OPERATING REGION
CVR --
KNEE VT(min) SELF-BREAKDOWN REGION
VT(IN) Volts DC 20-40 100-200
CT µF 2.2 0.10
CUTOFF REGION
OPERATING RANGE
XFMR TR-2189/2206 TR-2190/2207
E-E(co) E-E(min)
E-E(max)
SBV
E-E = ELECTRODE-TO-ELECTRODE VOLTAGE
Figure 1. Triggered Spark Gap Test Circuit
Figure 3. Transfer Characteristics
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PerkinElmer Optoelectronics
The trigger transformer circuit must be capable of providing a small sustaining current, typically, a few tens of milliamperes for reliable triggering. the characteristic "ring down" of conduction current is used to compute circuit impedance. The circuit is mechanically designed to yield the lowest possible overall inductance and resistance. Excluding the CVR, a typical circuit resistance is 60 milliohms. Circuit inductance can vary from 30 to 50 nH.
Life
End of life is determined by changes in the gap's performance due to electrode erosion or gas cleanup. Prefire (firing without a trigger signal) or failure to fire (no fire with trigger applied) are typical symptoms determining end of life.
Life test data indicate reliable firing on many gaps after 2000 shots at 6000 amps peak current for 200 ns pulse width at 3.5 kV and load of 0.25 ohm. Life will be reduced with higher peak currents.
0.020 ± 0.010 (0.51)
0.270 ± 0.010 (6.06)
0.314 ± 0.005 (7.98)
Transfer Characteristics
For the GP-486 the operating range (E-E) is 2.0 to 4.0 kV with a minimum trigger voltage (VT(OC)) open circuit of 2.0 kV. Static Breakdown Voltage (SBV) is 4.5 kV. Trigger mode is "C" positive trigger and positive opposite electrode (OE). Changing polarities will result in changes in operating characteristics. The triggered spark gap operating range is shown in Figure 3.
T
GP-485
AE 3.0 MIN. (76.2) 0.415 ± 0.015 (10.54) OE 0.415 ± 0.015 (10.54) 0.130 ± 0.015 (3.30) 0.437 ± 0.010 (11.10) 0.314 ± 0.005 (7.98)
0.105 ± 0.010 (2.67)
T
0.41 MAX (10.4)
GP-486
AE
3.0 MIN (76.2)
OE
0.025 (0.635) 0.010 (0.254)
0.267 ± 0.010 (6.78) 0.610 (15.5) MAX
0.325 MAX (8.25) 0.319 (8.1) MAX
OE
0.335 (8.5) MAX 0.098 (2.50) MAX
T AE
3.0 (76.2) MIN 0.370 ± 0.005 (0.94 ± 0.13) 0.064/0.120 1.63/3.05 0.267 , 0.010 (6.78 ± 0.254)
GP-488
0.247 ± 0.005 (6.27)
"same"
0.278 ± 0.010 (7.01 ± 0.25) 0.050 ± 0.010 (1.27 ± 0.25)
0.335 (8.51) MAX
OE AE
0.563 (14.30) MIN
GP-489
0.040 (1.02) TYP (2 PLCS) 0.247 ± 0.020 (6.27 ± 0.51)
T
0.040 ± 0.003 (1.016) 0.015 ± 0.005 (0.38 ± 0.13) (2 PLCS) 0.147 ± 0.015 (3.73 ± 0.38)
T -- Trigger Electrode; AE -- Adjacent Electrode; OE -- Opposite Electrode Mechanical Specifications
PerkinElmer Optoelectronics
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