CHICAGOMINIATURE LAMP, INC. WHERE INNOVATION COMES TO LIGHT

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1 Tel: Fax: Neon pplication Information Lamp Construction The basic construction of neon lamps is shown in figure 1. The bulb is made of glass sealed in two areas, the pip and the pinch. In the pinch area, the leads protrude through one end of a glass tube and the glass is heated and pinched about the leads. This holds them in position and forms a hermetic seal. The leads are made from a special material known as dumet which is a low resistance material consisting of a copper sheath around a nickel iron core constructed so that its expansion coefficient is the same as that of the glass used for the bulb. utt welded to the lead wires are nickel electrodes of larger diameter. These electrodes are coated with aspecial emissive material prior to being sealed into the glass bulb. This emissive coating has a lower work function than the base material andcauses the neon lamp to have a lower striking voltage than would otherwise be the case. The sealed unit is evacuated and an inert gas is introduced via the pip prior to tipping off. The neon lamp is commonly used without a base in "wireterminal" form, and is available with or without a resistor. Versions are available mounted on a metal or plastic base for replaceable use in a corresponding lampholder or fitting. Lamps mounted on bases are available without a resistor or with a resistor incorporated inside the base for direct operation from main voltage supplies. These lamps consist of a T2 neon lamp with a series resistor welded on, mounted in the metal base with a plastic top cap as shown in Figure 2. asic Principles of Lamp Operation Neon lamps have the voltage/current relationship shown in Figure 3, which determines their operation. s the applied voltage is increased there is virtually no current flow until the striking voltage is reached at point. The current then increases to a Voltage, V 1 Current, I Gas Glass Envelope Electrodes Voltage/Current C haracteristic for Neon Lamps 1 C C 1 Neon Lamp Construction Pip Pinch Leads ased Neon Lamp Construction I V Plastic Top Cap Neon Lamp Resistor Metal ase Figure 1 Figure 2 Figure 3 51 value 1 which is largely determined by the impedance of the external circuit, and the voltage across the neon lamp reduces to a lower value, known as the maintaining voltage. Further increasing the supply voltage (or reducing the external impedance) increases the lamp current with little change to the maintaining voltage until point 1 is reached. Then the maintaining voltage increases with current to a point C when the neon lamp discharge changes from a glow to an arc and the voltage across the lamp drops to a few volts at C 1. Neon lamps should be operated in the range to 1 which is called the "negative glow" region. 1 to C is the "abnormal glow" region and from C1 beyond is the "arc" region. neon lamp operates in the following manner: when the applied voltage is in excess of the striking voltage, electrons are emitted from the surface of the negative electrode (cathode) and, accelerated by the electric field, collide with atoms of gas. One of two reactions occur: 1. The traversing electron can collide with an atom of gas and elevate one of its valence electrons to a higher energy state. t some time after being elevated, the electron will return to a lower energy state and a photon of light will be emitted. The wavelength of the light output is determined by the difference in energy levels, which will be dependent upon the type of gas used. The total light output from a neon lamp is the result of millions of such occurrences at a given instant. 2. The atom can have an electron knocked off, in which case the atom becomes a positively charged ion. This ion is attracted by the negative electrode (cathode) and accelerated towards it. On colliding with the cathode, the ion causes material to be removed, a phenomenon known as sputtering. The emissive coating on the electrodes of neon lamps is removed by ionic bombardment so that eventually the base metal is exposed and the striking voltage of the lamp increased. When the lamp is operated from an a.c. supply, each electrode is alternately positive (anode) and negative (cathode) and material is sputtered from them during alternate half cycles. However, when the lamp is operated from a d.c. supply, one electrode is constantly the cathode and material is removed from it during the entire time that the neon lamp is operating. Consequently, the effects of sputtering become apparent earlier during d.c. operation and the lamp life expectancy is about 60% of that when operated from an a.c. supply. For reliable operation, neon lamps require some free charged particles to be present in the tube to initiate the glow discharge when an operating voltage is applied. These charged particles can be created by photoemission from the emissive surface of the electrodes, so that if the lamp is used in normal light no ignition problems should be encountered. Dark Effect If the lamp is used in total darkness, some ignition delay can occur unless a tube which contains a small amount of radioactive material is used. Operation in total darkness is normally only encountered in situations where the neon lamp is being used as a circuit component (i.e., its electrical characteristics are of prime importance, its indicating property being of secondary or no importance). In this case a cold cathode diode should be specified which is "dark effect" reduced.

2 Tel: Fax: Neon pplication Information Lamp Characteristics The main characteristics of neon lamps are detailed as follows. In general, these characteristics are not tightly controlled, as the prime function of the device is to emit light to act as an indicator. If a tube having a more controlled electrical specification is required for use as a circuit component, a cold cathode diode should be used. Light Output: Neon lamps are available from Chicago Miniature Lamp in two light output ranges (standard and high brightness). The standard brightness types have a light output of approximately.06 lumens per m, and the high brightness types emit approximately.15 lumens per m. The light output of neon lamps is mainly in the yellow and red regions of the spectrum between 580 and 750 nanometers with a band in the infrared between 820 and 880 nanometers. Striking Voltage: The voltage at which the neon lamp ignites is usually between 45 and V a.c. for standard brightness types and between 70 and V a.c. for high brightness types. This is sometimes called the breakdown or ignition voltage. Maintaining Voltage: The voltage across the lampafterithas ignited. This voltage is a function of the lamp current and is usually quoted at the design current. Nominal values are 60V for standard brightness and 75V for high brightness lamps. Extinction Voltage: The voltage at which the lamp extinguishes if the supply voltage is reduced. It is normally a few volts below the maintaining voltage. Design Current: The current at which the lamp has been designed to operate. It will be determined by the supply voltage and the value of series resistance. Operation at lower currents can result in the glow discharge becoming unstable (i.e., flickering) and operation at higher currents can severely reduce the useful life of the lamp. It is therefore important to use only the recommended value of series resistance. Operating Temperature: Neon lamps can be used up to a maximum temperature of 160 C, but for optimum life it is recommended that wherever possible the operating temperature should be within the range 50 C to + C. However, it should be noted that carbon film resistors which are recommended for use in series with neon lamps are normally derated, for maximum power dissipation, at temperatures above 70 C. Therefore, at higher temperatures other types of resitor, such as metal oxide, may be more suitable and resistor manufacturers' data should be consulted. Leakage Resistance: This is not a specified parameter, but in practice values in excess of 10 ohms will apply to wire terminal lamps. Measurements should always be taken in total darkness as photoemission from the electrodes 9 under ambient illumination will result in false, low resistance readings. The voltage at which leakage resistance is measured should be at least 10V below the minimum striking voltage of the lamp. end of its useful life. ecause the minimum acceptable light output value will depend upon the application, it is difficult to quote precise lifetimes, but values for 50% reduction of initial light output levels are given in Table 1. Since in most applications the lamp will not be operating all of the time, the actual life of the lamp in the equipment will be considerably longer than the quoted life. It should also be noted that because the blackening initially occurs around the sides of the glass bulb, a longer lifetime is usually achieved if the lamp is endviewed. The life expectancies quoted in Table1 apply to neon lamps operated from an a.c. supply. s explained earlier in these notes, when the lamps are operated from a d.c. supply, lifetimes are Table 1 Typical Life Expectancies of Neon Lamps Operated from an C Supply rightness Level Life Expectancy Standard High hours 8,000 hours For DC life expectancies, see text. approximately 60% of these values. In order to obtain the maximum lifetime it is recommended that ±5% carbon film series resistors be used. Variations in supply voltage will also affect the life of the lamp due to the resultant change in operating current. The relationship between operating current and life can be expressed as a 3.3 power law, I 1 L 2= L 1 ( I ) 3.3 R or L 2= L 1 ( R ) where L is the life expectancy at the design current I with the recommended series resistance R, and L is the life expectancy at current I with the series resistance R.. This relationship, which is shown graphically in Figure 4, is approximate and should only be used as a guide to the effect on life for changes in operating current. It should not be used to estimate lifetimes when the current is more than twice the design current, since other factors, such as heating of the electrodes, will cause an even greater reduction in lifetime. Operation at currents lower than the design current will theoretically result in increased life expectancy. However, this is not recommended as the discharge may become unstable initially or after a period of low current operation. Green Fluorescent Lamps The basic difference between green fluorescent and neon lamps is that the gas discharge (glow) in the neon lamp is directly viewed through the transparent glass bulb. In the case of the green lamp, the inside of the glass bulb is treated with a fluorescent coating which emits a green light when the gas is ionized Life Expectancy The end of life of a neon lamp is usually a catastrophic failure, but is an arbitrary condition when the light output has reduced to an unacceptably low level. During the life of a neon lamp, material is sputtered from the electrodes and some of this adheres to the wall of the glass bulb which has the effect of reducing the light output. The process is a gradual one, and not until many thousands of hours of normal operation will the blackening be such that the light output has fallen below an acceptable level and the lamp be at the Life Factor Figure Operating Current/Design Current 52

3 Tel: Fax: Series 5314N1 and 5314N2 PC oard Mounted Neon MX..300 MX..130 Ø.160 MX S TNDOFF.1±.060 Lamp Leads (tinned).100* FOR POST CLENING * ll dimensions in. *Note: These dimensions are at the base of holder..450 MX.* oard Mounted Neon Lamp Easy to mount. Pressin mounting for accurate location on printed circuit board. Mounting pattern on page 1X3. Includes board standoff to prevent flux entrapmentpermit easy washing. Housing: lack Nylon Lamp: Lamp Model Incorporates Lamp No. 5314N1 5314N2 1MH 2ML See page 54 for complete lamp specifications. 53

4 Tel: Fax: Neon Indicator Lamps Configuration Wire TerminalS tandard rightness Wire TerminalHigh rightness C C Part 2ML 1 1T 1 1D 1DT K4 2 2T 9 9T 9C 9CT 1MH 1C 1CT G21 G22 3C 3CT C2 C2T C2C D2 Old Ref. NE38S NE2 NE2T R 9 NE2V NE2VT NE2E NE2ET NE2E1 NE2E1T NE38 NE2U NE2UT NE2H NE2HT NE2H1 Design Current m Maximum reakdownvoltage VC VDC Life value is to approximately 50% of initial light output. Values shown apply to use on C unless otherwise shown. Life on DC is approximately 60% of C values when DC current is equal to RMS C value. When equal DC and RMS C voltages and equal resistances are utilized, life will be approximately the same. 2. For DC operation of high brightness lamps use a minimum of 150 circuit volts. Maximum initial breakdown voltage VC, VDC in light. 3. Tinned leads. 4. High brightness. 5. Formed tip. 6. Dark effect reduced. 7. Lamp drops through a Ø.310" cylinder of " minimum length. 54

5 Tel: Fax: V V Ohms W Ohms W Wire TerminalS tandard rightness 220K 540K 540K 220K 540K 220K 540K 220K 540K 220K 540K 220K 220K 220K 220K 220K 220K Wire TerminalHigh rightness 47K 47K 47K 47K 39K 22K Series Resistor 150K 150K 150K 150K 120K 68K verage Useful Life (Max.) (Max.) ,3,5,6 1,3,5,6 14,6 1,3,5,6 1,3,5 1,3,5 1,4,5 2,4,5,6,8 2,3,4,5,6,8 1,4,5,13 1,4,5,13 2,4,5,6,8,9 2,3,4,5,6,8,9 2,4,5,6,8 2,3,4,5,6,8 2,4,5,6,8 2,4,5,6,8,10 8. Life values shown apply to use on C unless otherwise shown. End of life occurs when breakdown voltage increases to line voltage and lamp will no longer start. With equal DC and RMS C current, life willbesomewhat lower than the 60% value quoted for standard brightness lamp. 9. Maximum breakdown voltage in total darkness 100VC. 10. Minimum current for stable operation 1.5m. 11. Resistor included in ase. 12. Caution: ulb may shatter and/or circuit may be damaged without external series resistance. 13. Green fluorescent. 14. rgon gas filled. 55

6 Tel: Fax: V V Ohms W Ohms W Wire TerminalS tandard rightness 220K 540K 540K 220K 540K 220K 540K 220K 540K 220K 540K 220K 220K 220K 220K 220K 220K Wire TerminalHigh rightness 47K 47K 47K 47K 39K 22K Series Resistor 150K 150K 150K 150K 120K 68K verage Useful Life (Max.) (Max.) ,3,5,6 1,3,5,6 14,6 1,3,5,6 1,3,5 1,3,5 1,4,5 2,4,5,6,8 2,3,4,5,6,8 1,4,5,13 1,4,5,13 2,4,5,6,8,9 2,3,4,5,6,8,9 2,4,5,6,8 2,3,4,5,6,8 2,4,5,6,8 2,4,5,6,8,10 8. Life values shown apply to use on C unless otherwise shown. End of life occurs when breakdown voltage increases to line voltage and lamp will no longer start. With equal DC and RMS C current, life willbesomewhat lower than the 60% value quoted for standard brightness lamp. 9. Maximum breakdown voltage in total darkness 100VC. 10. Minimum current for stable operation 1.5m. 11. Resistor included in ase. 12. Caution: ulb may shatter and/or circuit may be damaged without external series resistance. 13. Green fluorescent. 14. rgon gas filled. 55

7 Tel: Fax: Neon Indicator Lamps Configuration T4 1/2 Candelabra S crew ase Part 7 F3 F4 J2 Old Ref. NE45 NE57 NE58 R 3 Design Current m Maximum reakdown Voltage VC VDC T4 1/2 S.C. ayonetase 6 8 NE21 NE T4 1/2 D.C. ayonetase 5 9 NE17 NE S7 D.C. ayonetase R1 NE Life value is to approximately 50% of initial light output. Values shown apply to use on C unless otherwise shown. Life on DC is approximately 60% of C values when DC current is equal to RMS C value. When equal DC and RMS C voltages and equal resistances are utilized, life will be approximately the same. 2. For DC operation of high brightness lamps use a minimum of 150 circuit volts. Maximum initial breakdown voltage VC, VDC in light. 3. Tinned leads. 4. High brightness. 5. Formed tip. 6. Dark effect reduced. 7. Lamp drops through a Ø.310" cylinder of " minimum length. 56

8 Tel: Fax: Series Resistor V V Ohms W Ohms W T4 1/2 Candelabra S crew ase 15K verage Useful Life 7, (Max.) (Max.) ,14 T4 1/2 S.C. ayonetase 7,500 T4 1/2 D.C. ayonetase 7,500 S7 D.C. ayonetase 8. Life values shown apply to use on C unless otherwise shown. End of life occurs when breakdown voltage increases to line voltage and lamp will no longer start. With equal DC and RMS C current, life willbesomewhat lower than the 60% value quoted for standard brightness lamp. 9. Maximum breakdown voltage in total darkness 100VC. 10. Minimum current for stable operation 1.5m. 11. Resistor included in ase. 12. Caution: ulb may shatter and/or circuit may be damaged without external series resistance. 13. Green fluorescent. 14. rgon gas filled. 57

9 Tel: Fax: Series Resistor V V Ohms W Ohms W T4 1/2 Candelabra S crew ase 15K verage Useful Life 7, (Max.) (Max.) ,14 T4 1/2 S.C. ayonetase 7,500 T4 1/2 D.C. ayonetase 7,500 S7 D.C. ayonetase 8. Life values shown apply to use on C unless otherwise shown. End of life occurs when breakdown voltage increases to line voltage and lamp will no longer start. With equal DC and RMS C current, life willbesomewhat lower than the 60% value quoted for standard brightness lamp. 9. Maximum breakdown voltage in total darkness 100VC. 10. Minimum current for stable operation 1.5m. 11. Resistor included in ase. 12. Caution: ulb may shatter and/or circuit may be damaged without external series resistance. 13. Green fluorescent. 14. rgon gas filled. 57

10 Tel: Fax: Neon Indicator Lamps Configuration G10 D.C. ayonetase Part L5 Old Ref. NE32 Design Current m 8.0 Maximum reakdown Voltage VC VDC S11 MediumScrewase J9 J5 NE56 NE S14 MediumScrewase R2 W1 R6 NE34 R 1 NE S14 D.C. ayonetskirtedase R9 NE Life value is to approximately 50% of initial light output. Values shown apply to use on C unless otherwise shown. Life on DC is approximately 60% of C values when DC current is equal to RMS C value. When equal DC and RMS C voltages and equal resistances are utilized, life will be approximately the same. 2. For DC operation of high brightness lamps use a minimum of 150 circuit volts. Maximum initial breakdown voltage VC, VDC in light. 3. Tinned leads. 4. High brightness. 5. Formed tip. 6. Dark effect reduced. 7. Lamp drops through a Ø.310" cylinder of " minimum length. 58

11 Tel: Fax: Series Resistor V V Ohms W Ohms W G10 D.C. ayonetase 7.5K 25K verage Useful Life (Max.) 9 (Max.) 2.13 S11 MediumScrewase 39K 7.5K S14 MediumScrewase 3.5K 3.5K 2.5K 1, ,14 S14 D.C. ayonetskirtedase 2.2K 7.5K Life values shown apply to use on C unless otherwise shown. End of life occurs when breakdown voltage increases to line voltage and lamp will no longer start. With equal DC and RMS C current, life willbesomewhat lower than the 60% value quoted for standard brightness lamp. 9. Maximum breakdown voltage in total darkness 100VC. 10. Minimum current for stable operation 1.5m. 11. Resistor included in ase. 12. Caution: ulb may shatter and/or circuit may be damaged without external series resistance. 13. Green fluorescent. 14. rgon gas filled. 59

12 Tel: Fax: Series Resistor V V Ohms W Ohms W G10 D.C. ayonetase 7.5K 25K verage Useful Life (Max.) 9 (Max.) 2.13 S11 MediumScrewase 39K 7.5K S14 MediumScrewase 3.5K 3.5K 2.5K 1, ,14 S14 D.C. ayonetskirtedase 2.2K 7.5K Life values shown apply to use on C unless otherwise shown. End of life occurs when breakdown voltage increases to line voltage and lamp will no longer start. With equal DC and RMS C current, life willbesomewhat lower than the 60% value quoted for standard brightness lamp. 9. Maximum breakdown voltage in total darkness 100VC. 10. Minimum current for stable operation 1.5m. 11. Resistor included in ase. 12. Caution: ulb may shatter and/or circuit may be damaged without external series resistance. 13. Green fluorescent. 14. rgon gas filled. 59

13 Tel: Fax: Neon Indicator Lamps Configuration T2 Midget Flange ase T2 Telephone S lide ase C Part 1G 1GR 1H 1HR C7 C7R C9 C9R G9 G9R K1C5 K1C5R K11 K11R K15 K15R Old Ref. NE2D NE2J NE84 Design Current m Maximum reakdown Voltage VC VDC T3 Miniatureayonetase 1 1R 2 2R 2G 2GR NE51 NE51R NE51H NE51HR NE51G R 51GR 1. Life value is to approximately 50% of initial light output. Values shown apply to use on C unless otherwise shown. Life on DC is approximately 60% of C values when DC current is equal to RMS C value. When equal DC and RMS C voltages and equal resistances are utilized, life will be approximately the same. 2. For DC operation of high brightness lamps use a minimum of 150 circuit volts. Maximum initial breakdown voltage VC, VDC in light. 3. Tinned leads. 4. High brightness. 5. Formed tip. 6. Dark effect reduced. 7. Lamp drops through a Ø.310" cylinder of " minimum length. 510

14 Tel: Fax: Neon Indicator Lamps Series Resistor V V Ohms W Ohms T2 MidgetFlange ase 220K 540K 220K 47K 150K 47K 220K 47K 150K 47K T2 Telephone S lide ase 220K 47K 150K 47K W verage Useful Life 1 1 (Max.) (Max.) ,12,11 2,4,5,6,8,12 2,4,5,6,8,11,12,11 2,4,5,6,8,12 2,4,5,6,8,11,12,13,11,13,7,12,7,11 2,4,6,7,8,12 2,4,6,7,8,11 2,4,5,6,7,8,12 2,4,5,6,7,8,11 T3 Miniatureayonetase 220K 540K 220K 47K 150K 47K 47K 150K 47K ,4,6,8 2,4,6,9,11 2,4,5,13 2,4,5,11,13 1. Life value is to approximately 50% of initial light output. Values shown apply to use on C unless otherwise shown. Life on DC is approximately 60% of C values when DC current is equal to RMS C value. When equal DC and RMS C voltages and equal resistances are utilized, life will be approximately the same. 2. For DC operation of high brightness lamps use a minimum of 150 circuit volts. Maximum initial breakdown voltage VC, VDC in light. 3. Tinned leads. 4. High brightness. 5. Formed tip. 6. Dark effect reduced. 7. Lamp drops through a Ø.310" cylinder of " minimum length. 511

15 Tel: Fax: Neon Indicator Lamps Series Resistor V V Ohms W Ohms T2 MidgetFlange ase 220K 540K 220K 47K 150K 47K 220K 47K 150K 47K T2 Telephone S lide ase 220K 47K 150K 47K W verage Useful Life 1 1 (Max.) (Max.) ,12,11 2,4,5,6,8,12 2,4,5,6,8,11,12,11 2,4,5,6,8,12 2,4,5,6,8,11,12,13,11,13,7,12,7,11 2,4,6,7,8,12 2,4,6,7,8,11 2,4,5,6,7,8,12 2,4,5,6,7,8,11 T3 Miniatureayonetase 220K 540K 220K 47K 150K 47K 47K 150K 47K ,4,6,8 2,4,6,9,11 2,4,5,13 2,4,5,11,13 1. Life value is to approximately 50% of initial light output. Values shown apply to use on C unless otherwise shown. Life on DC is approximately 60% of C values when DC current is equal to RMS C value. When equal DC and RMS C voltages and equal resistances are utilized, life will be approximately the same. 2. For DC operation of high brightness lamps use a minimum of 150 circuit volts. Maximum initial breakdown voltage VC, VDC in light. 3. Tinned leads. 4. High brightness. 5. Formed tip. 6. Dark effect reduced. 7. Lamp drops through a Ø.310" cylinder of " minimum length. 511

16 Tel: Fax: Neon Circuit Component Lamps Configuration Wire Terminal C Part 2 2C 3D 3G 3G 3GC 3GF 3H 3J 3JC 4D 4E T 5T 5C 5G 5G 5H 5H 5H 5HD 5HE 5J 5J 5J Old Ref. NE99 NE98 NE23 NE68 NE81 NE76 NE83 NE86 Design Current m Initial DC reakdown Voltage Max Initial DC Maintaining Voltage 5262 vg.>50 vg.> Max. vg.70 vg.>59 vg.> vg vg vg.> vg.>61 vg.>

17 Tel: Fax: reakdownvoltage Chg. Hrs. Wire TerminalS tandard rightness verage Life to Indicate C hange ,000 3,000 1,000 Maintain Voltage Chg. Hrs , , , (Max.) (Max.)

18 Tel: Fax: reakdownvoltage Chg. Hrs. Wire TerminalS tandard rightness verage Life to Indicate C hange ,000 3,000 1,000 Maintain Voltage Chg. Hrs , , , (Max.) (Max.)