1、,K- aC-4 0 SAE ARP*84b b5 W 83573LO 0029363 7 W AEROSPACE R ECO M MEN D ED P R ACT1 CE ;OCIETV OF AUTOMOTIVE ENOINEERS. he. 485 LEXINGTON AVENUE NEW YORK ?7s N.Y. LOW TENSION SPARK IGNITER SPARKING VLTAGE TEST ARP 846 IUU 2-10-6s Roviwd 1, PURPOSE - The purpose of these specifications is to provide
2、a standard procedure and standard equipment for the evaluation of a measurement of the ionization voltage (sparking voltage) of shunted surface gap spark igniter designs. 2. SCOPE - These specifications contain general information pertaining to the sparking voltage parameter of shunted surface gap s
3、park igniters; test equipment circuitry; bill of materials for test equipment; test equipment operation. 3. GENERAL CONSIDERATIONS CONCERNING SPARKING VOLTAGE MEASUREMENTS AS A SHUNTED SURFACE SPARK IGNITER PARAMETER 3.1 3i 2 3.3 Spark Igniter Configuration - The low tension type of spark igniter ut
4、ilizes a material classified as a semi-conductor to bridge the gap from the center electrode to the oute: or ground shell. Thus, this design is referred to as the shunted surface gap spark igniter as well as the low tension spark igniter. When the shunted surface material is in good condition and in
5、 intimate contact with the electrodes, the spark igniter gap can be forced to break down (ionize gases between electrodes) at a lower voltage than would occur if the shunt were removed. The voltage required to break down the gap increases with deterioration of the shunted gap material and the deteri
6、oration of the materials contact with the igniter electrodes. Sparking Voltage - By definition, the sparking voltage of a particular shunted surface gap spark igniter design is the lowest voltage applied to an igniter which will initiate a spark. The term “initiate“ is used since the maintenance of
7、the sparking conditions and energy dissipation is a function of the igniter gap itself and the applied voltage. Sparking voltages may be used as a measure of the condition of shunted surfaces and of contact conditions between electrodes and surface. It is also conceivable that sparking voltages may
8、be used as an indicator of life expectancy of new and used spark igniters providing that all use-conditions are taken into account. New Spark Igniter Limit - It has been established that for new spark igniters the sparking voltage should be less than 1000 volts under room conditions. This test value
9、 assures that the spark igniter life will be a function of engine environment and use and that the unit has been properly assembled. It must be noted here that spark- ing voltages of a very low magnitude (below 200 volts) may indicate abnormal semi- conductor material conditions. Consideration shoul
10、d therefore be given to establish- ing a minimum as well as a maximum sparking voltage for a given igniter design. 4. TEST EQUIPMENT FOR MEASURING LOW TENSION SPARK IGNITER SPARKING VOLTAGES 4.1 General Test Procedure - .- CODYrhht 1g65 )r Oodotu o Automotko Lnrlnoorr. Ina Printed in U 1. A. - _ SAE
11、 ARP*84b b5-i 8357340 00273b2 3 IMU 2-10-65 LOW TENSION SPARK IGNITER SPARKING VOLTAGE TEST -2- 4.1.1 New Spark Igniters - A new spark igniter, when connected to a power source con- sisting o cr previously charged O. 5 microfarad capacitor at 1000 volts maximum, shall produce a readily visible spark
12、 between the two metal electrodes. It is rec- ommended that a minimum of five (5) successive sparks be used to establish com- pliance to the maximum voltage requirements. 4.1.2 Old Spark Ignitrs - The test equipment must be capable of applying voltages adjust- ed between 1000 volts (for new spark ig
13、niters) and 5000 volts. The test operator shall us0 his experience to determine the voltage level that the O. 5 microfarad capacitor is to be charged to for the teat. Repetitive tests parallel to that for new spark igniters niay be used to determine the actual sparking voltage or the test may be con
14、fined to determining if the sparking voltage is less than a specified limit. 4,2 4.2. 4.2.2 Tost Equipment General - The output characteristics of the spark igniter tester shall be such, that when it imposes a positive pulse across a O, 3 ohm resistor (inductance rating O. 35 to O. 375 microhenry at
15、 10 kc) from a O. 5 microfarad capacitor charged to 2000 v, tho voltage rise across the resistor shall exceed 200 v within a time period of 1.5 microseconds. (Reference: Tektronic Scope No. 531 or equivalent may be used to rnoatmro the voltage rise or if the voltage rise is too high for this equipme
16、nt a Tektronio High Voltage Probe No. P6002, Part Number 010-024 or equivalent may be used,) -c- NOTE: A negative pulse may be used instead of a positive pulse; however, one polarity must be chosen, as it is felt that difference may exist and an igniter measured ns satisfactory on one may be unsatis
17、factory on the other, “he test equipment circuit described in this document is one of many possible cir- cuit deisigns which would satisfy the above requirements. Circuit Description - The test equipment designed to accomplish the general test functions has three major circuit elements: input circui
18、t, power circuit and oscil- lator circuit. These circuit elements are connected to charge and/or discharge a O. fi microfarad capacitor to voltage levels from O to 5000 v d-c at a discharge rate of approximately two (2) sparks per second. The detailed circuit schematic is shown in Figure 1, “he teet
19、er consists of a main housing which contains the circuitry shown on the schematic diagram and an adapter box which provides for enclosure of the test piecs. S-3 is an interlock switch that is incorporated in the cover of the main housing and S-4, also an interlock switch, is mounted in the enclosure
20、 for the test piece. The cover of both the tester and adapter box has to be closed in order to energize the high voltage supply located in the tester. SAE ARPm846 65 m 83573LiO 0027363 O m LOW TENSION SPARK IGNITER SPARKING .VOLTAGE TEST e e 4 -0 ARP 846 Issued 2-10-65 Revised -3- The front panel of
21、 the tester contains two toggle switches (S-1, S-2), two pilot lamps (DS-1, DS-2), a variac for voltage adjustment (T-1), a calibrated volt- meter (M-1), and selector switch (S-6) for full scale meter readings of 2.5 and 5. O kilovolts. The push button switch (S-5) when depressed, will cause M-1 to
22、indicate the voltage that the tank capacitor C-1 is charged to. 4.2.3 Detailed Circuit Description 4.2.3.1 4.2.3.2 4.2.3.3 Input Circuit - When S-1 is closed, voltage is applied to DS-1, the primary of T-4 and the filaments of K1, V-1, V-2 and V-3. DS-1 will light and d-c voltage will exist on C-2 a
23、nd C-3 of the d-c power supply circuit. The time delay relay K-1 will close in approximately 60 seconds. S-2 and S-3 are mechanical interlocks with the lid of the tester and the lid of the adapter box respectively. With both lids closed, S-2 may be closed applying powei to DS-2 and the coil of K-2.
24、Thus, the variac T-1 is energized, the charging cir- cuit is energized and the change readout meter interlock circuit is armed. T-1 determines the voltage to be applied to T-2 and thus determinesthe charge voltage on the tank capacitor C-l. Power Circuit - The power circuit consists mainly of T-1, T
25、-2, V-1, R-1, C-1 and is such that C-1 will charge to a peak value within O. 2 seconds. This assures that the tank capacitor (C-i) will always be charged to the peak value at the time that the igniter is connected to the test circuit. When S-5 of the meter interlock circuit is depressed, K-4 will en
26、ergize and K-6 will de-energize. K-4 will connect the meter M-1 across C-1 and K-6 will short C-4 removing the EH- from V-3. V-3 will cease to oscillate and M-1 will indicate the voltage across C-1 allowing the voltage across the tank capacitor (C-i) to be adjusted. When S-5 is released, the meter i
27、s removed from the circuit and the oscillator circuit will start to function. The pre-set voltage will then be impresse on the spark igniter connected at the output terminals at a rate of approximately two times a second. Switch S-4 is located in the adapter box containing the spark igniter under te
28、st. When the cover of the adapter box is opened, S-4 would be in a normally open position de-energizing K-2. This in turn would remove the high voltage from C-1, and K-3 would de-energize shorting C-1 through R-2 and R-3. Thus, the high voltage is removed from the spark igniter to provide for operat
29、or protection. Oscillator Circuit - The oscillator determines the firing rate of the test circuit by momentarily energizing K-5 and thus connecting the test spark igniter to the test circuitry. The oscillator circuit consists of a power supply containing T-4, V-2, R-6 , R-7, C-2 and (2-3 and a grid
30、bias circuit -element containing CR-1 , R-12, -. SAE ARP*BYb 65 R 83573YO 00293bY 2 JRp 846 Irruod 2-10-65 Rhd SPARKING VOLTAGE TEST LOW TENSION SPARK IGNITER -4- (2-6, R-9, R-IO, R-11, R-13 and C-5. The anode voltage on V-3 and the firing rate is controlled by an RC network consistng of R-14, R-8 a
31、nd C-4. Adjustment of the firing rate may be made by adjusting R-8 and R-10. The energy stored in (2-4 causes the relay K-5 to operate momentarily when the voltage across the re- lay coil reaches the relays pull-in value. The peak output voltage of the oscillator is equal to 65% of the voltage appea
32、ring across c-3. 4.2.4 rest Circuit Component - Table 1 presents a parts list for the test equipment de- scribed in this specification, The K-5 relay was adapted from a standard relay. Pigireis 2, 3, and 4 show the modification information necessary to obtain a K-5 relay. PREPARED BY SUBCOMMITTEE E-
33、30A AIRCRAFT GAS TURBINE AND RAM-JET ENGINE IGNITION, OF SAE COMMITTEE E-30, IGNITION RESEARCH LOW TENSION SPARK IGNITER SPARKING VOLTAGE TEST c-1 c-2 c-3 c-4 c-5 C-6 c-7 CR-1 DS-1 DS-2 F- 1 K- 1 K-2 K-3 K-4 K-5 K-6 P-1 P-2 R-1 R-2 R-3 R-4 R-5 R-6 R-7 R- 8 R-9 R-10 R-11 R-12 R-13 s-1 s-2 AM 846 lasu
34、ed 24-65 Revised -5- TABLE 1 PARTS LIST FOR TEST CIRCUIT Capacitor O. 5 mfd, 10 kv, EP100-504 Capacitor, 10 mfd, 450 v, BR 1045 Capacitor 10 mfd, 450 v, BR 1045 Capacitor 3 mfd, 600 v, TJU-6050 Capacitor O. O01 mfd, 600 v, PM-6D1 Capacitor 25 mfd, 25 v, BR-25-25 Capacitor .O2 mfd, 600 v, PM-6S2 Rect
35、ifier CX2E4U Pilot assembly 9 5408-93 1 Pilot assembly 95408-931 Fuse assembly 342001 Relay 115N060 SPST Relay MR5A, 115 v, SPDT Relay A-300, 115 v, DPDT Relay A-300, 115 v, DPDT Relay, special, L-9928-53 Relay MR5A, 115 v, SPST Plug P-302-CCT Re ceptacle S-3 02-AB Plug P-304-CCT Receptacle S-304-AB
36、 Resistor 5K, lOOW, adj. 0964 Resistor lOOK-lOOW, 0625 Resistor 1OOK-lOOW, 0625 Resistor 10 meg, 2W, DCH, 1% lOmeg, 2W, DCH, 1% 5meg, 2W, DCH, 1% Resistor, 20 meg, 2W, DCH, 1% 20 meg, 2W, DCH, 1% lOmeg, 2W, DCH, 1% Resistor 470 ohms, 1W Resistor 1000 ohms, 1W Resistor 100K, 2W, CLU-1041 Resistor 27K
37、, 2W Potentiometer 100K, 2W, CLU 1043 Resistor O. 1 meg, 1W Resistor 1000 ohms, 2W Ref. R-11 Switch SPST 34-086 Switch SPST 34-086 Plastic Capacitors Cornell-Dublier Cor ne11 - Dub1 ie r C orne11 -Dub1 ie r Cornell-Dublier Cornell-Dublier Cornell-Dublier Bradley Laboratories Dialco Dialco Little fus
38、e Amperite Potter Rovimd IARP 846 LOW TENSION SPARK IGNITER SPARKING VOLTAGE TEST -8- n t- ? 5: 2 I c SAE ARP*B96 65 83573LiO 0029369 L LOW TENSION SPARK IGNITER SPARKING .VOLTAGE TEST ARP 846 Irsued 2-10-65 Revised -9- I n SAE ARP*44b b5 -83573YO OOZ9370 U 846 luud 2-10-61; LOW TENSION SPARK IGNITER RovlrJ . SPARKING VOLTAGE TEST - 10 - 0 o tu I I VI o a (u
