"C" III Series S E M I C O N D U C T O R Radial Lead Metal-Oxide Varistors June1995 Features * Recognized as "Transient Voltage Surge Suppressors" to UL 1449; File # E75961 * Recognized as "Transient Voltage Surge Suppressors" to CSA C22.2, No. 1; File # LR91788 * High Energy Absorption Capability WTM . . . . . . . . 45J to 210J (2ms) * High Peak Pulse Current Capability ITM . . . . 6000A to 9000A (8/20s) * Wide Operating Voltage Range VM(AC)RMS . . . . . . . . . . . 130V to 320V "C" III SERIES * Available in Tape and Reel for Automatic Insertion; Also Available with Crimped and/or Trimmed Lead Styles Description The expanded version of the LA series of metal-oxide varistors, designation "C" III series, consists of AC line voltage rated MOVs with extremely high current and energy handling capabilities. This new "C" III series of MOVs was primarily designed for the transient voltage surge suppressor (TVSS) environment. They provide the increased level of protection now deemed to be necessary for the transients expected in this environment. The occurrence of high volt- age transients in the AC power network can be detrimental to the associated line equipment. Such transient occurrences may cause product failure and the subsequent faulty operation of the electrical systems. This special version of the Harris 14mm and 20mm LA series of metal oxide varistors is also available with 10mm lead spacing, tape and reel, and in a variety of crimped and trimmed lead forms. Absolute Maximum Ratings For ratings of individual members of a series, see Device Ratings and Specifications chart "C" III SERIES UNITS Continuous: Steady State AC Voltage Range (VM(AC)RMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 to 320 V Transients: Single-Pulse Peak Current (ITM) 8/20s Wave (See Figure 2) . . . . . . . . . . . . . . . . . . . . . . . . . . . Single-Pulse Energy Range (WTM) 2ms Rectangular Wave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6000 to 9000 45 to 210 A J Maximum Temporary Overvoltage of VM(AC), (5 Minutes Duration) . . . . . . . . . . . . . . . . . . . . . . . . . . 130 (+25oC) 120 (+125oC) % % Operating Ambient Temperature Range (TA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to +85 oC Storage Temperature Range (TSTG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to +125 oC Temperature Coefficient (V) of Clamping Voltage (VC) at Specified Test Current. . . . . . . . . . . . . . <0.01 %/oC Copyright (c) Harris Corporation 1995 File Number 4-26 3540.3 Specifications "C" III Series "C" III Series Ratings MAXIMUM RATINGS (+85oC) CONTINUOUS MODEL NUMBER DEVICE MARKING TRANSIENT MAXIMUM VRMS VM(AC) (V) WITHSTANDING ENERGY (2ms) WTM ( ) (J) PEAK CURRENT (8/20s) ITM1 1 PULSE (A) ITM2 2 PULSES (A) V130LA10C V130LA20C V130LA20CX325 130L10C 130L20C 130LA20CX325 130 130 130 45 90 90 6000 9000 9000 5000 7000 7000 V140LA10C V140LA20C V140LA20CX340 140L10C 140L20C 140L20CX340 140 140 140 50 100 100 6000 9000 9000 5000 7000 7000 V150LA10C V150LA20C V150LA20CX360 150L10C 150L20C 150L20CX360 150 150 150 55 110 110 6000 9000 9000 5000 7000 7000 V175LA10C V175LA20C V175LA20CX425 175L10C 175L20C 175L20CX425 175 175 175 60 120 120 6000 9000 9000 5000 7000 7000 V230LA20C V230LA40C V230LA40CX570 230L20C 230L40C 230L40X570 230 230 230 80 160 160 6000 9000 9000 5000 7000 7000 V250LA20C V250LA40C V250LA40CX620 250L20C 250L40C 250L40CX620 250 250 250 100 170 170 6000 9000 9000 5000 7000 7000 V275LA20C V275LA40C V275LA40CX680 275L20C 275L40C 275L40CX680 275 275 275 110 190 190 6000 9000 9000 5000 7000 7000 V300LA20C V300LA40C V300LA40CX745 300L20C 300L40C 300L40CX745 300 300 300 120 210 210 6000 9000 9000 5000 7000 7000 V320LA20C V320LA40C 320L20C 320L40C 320 320 200 200 6000 9000 5000 7000 "C" III Series Specifications SPECIFICATIONS (+25oC) MODEL NUMBER MODEL SIZE DISC DIAMETER (mm) V130LA10C V130LA20C V130LA20CX325 VARISTOR VOLTAGE AT 1mA DC TEST CURRENT MAXIMUM CLAMPING VOLTAGE (8/20s) DUTY CYCLE SURGE RATING VN MIN (V) VN MAX (V) VC (V) Ip (A) 3kA (8/20s) # PULSES 750A (8/20s) # PULSES 14 20 20 184 184 184 228 228 220 340 340 325 50 100 100 10 20 20 80 120 120 V140LA10C V140LA20C V140LA20CX340 14 20 20 198 198 198 242 242 230 360 360 340 50 100 100 10 20 20 80 120 120 V150LA10C V150LA20C V150LA20CX360 14 20 20 212 212 212 268 268 243 395 395 360 50 100 100 10 20 20 80 120 120 V175LA10C V175LA20C V175LA20CX425 14 20 20 247 247 247 303 303 285 455 455 425 50 100 100 10 20 20 80 120 120 4-27 "C" III Series "C" III Series Specifications (Continued) SPECIFICATIONS (+25oC) MODEL NUMBER MODEL SIZE DISC DIAMETER (mm) V230LA20C V230LA40C V230LA40CX570 MAXIMUM CLAMPING VOLTAGE (8/20s) VARISTOR VOLTAGE AT 1mA DC TEST CURRENT DUTY CYCLE SURGE RATING VN MIN (V) VN MAX (V) VC (V) Ip (A) 3kA (8/20s) # PULSES 750A (8/20s) # PULSES 14 20 20 324 324 324 396 396 384 595 595 570 50 100 100 10 20 20 80 120 120 V250LA20C V250LA40C V250LA40CX620 14 20 20 354 354 354 429 429 413 650 650 620 50 100 100 10 20 20 80 120 120 V275LA20C V275LA40C V275LA40CX680 14 20 20 389 389 389 473 473 453 710 710 680 50 100 100 10 20 20 80 120 120 V300LA20C V300LA40C V300LA40CX745 14 20 20 420 420 420 517 517 490 775 775 745 50 100 100 10 20 20 80 120 120 V320LA20C V320LA40C 14 20 462 462 565 565 850 850 50 100 10 20 80 120 NOTE: Average power dissipation of transients not to exceed 0.6W and 1W for model sizes 14mm and 20mm, respectively Power Dissipation Ratings PERCENT OF PEAK VALUE 100 PERCENT OF RATED VALUE The metal oxide varistor is designed to absorb voltage transients of relatively short durations, not continuous over voltage. Therefore, unless transients occur in rapid succession, a continuous power dissipation capability is not an applicable design requirement for a varistor. Under this condition, the average power dissipation required is simply the energy (watt-seconds) per pulse times the number of pulses per second. The power so developed must be within the specifications shown on the Device Ratings and Specifications table for the specific device. The operating values of a MOV need to be derated at high temperatures as shown in Figure 1. Because varistors only dissipate a relatively small amount of average power they are not suitable for repetitive applications that involve substantial amounts of average power dissipation. 90 80 70 60 50 40 30 20 10 0 -55 50 60 70 80 90 100 110 120 130 140 150 AMBIENT TEMPERATURE (oC) FIGURE 1. CURRENT, ENERGY AND POWER DERATING CURVE 100 O1 = Virtual Origin of Wave T = Time From 10% to 90% of Peak T1 = Virtual Front time = 1.25 * t T2 = Virtual Time to Half Value (Impulse Duration) Example: For an 8/20s Current Waveform: 8s = T1 = Virtual Front Time 20s = T2 = Virtual Time to Half Value 90 50 10 O1 T TIME T1 T2 FIGURE 2. PEAK PULSE CURRENT TEST WAVEFORM 4-28 "C" III Series Transient V-I Characteristics Curves V320LA20C V300LA20C V275LA20C V250LA20C V230LA20C 1,000 MODEL SIZE = 14mm TA = -55oC TO +85oC 130 TO 320VM(AC) RATING 500 300 V175LA10C V150LA10C V140LA10C V130LA10C 200 100 10-3 10-2 10-1 100 101 102 PEAK AMPERES (A) 103 MAXIMUM PEAK VOLTAGE (V) V320LA40C V300LA40C V275LA40C V250LA40C V230LA40C 1,000 500 300 V175LA20C V150LA20C V140LA20C V130LA20C 200 100 10-3 104 FIGURE 3. MAXIMUM CLAMPING VOLTAGE FOR V130LA10C TO V320LA20C 1,000 MODEL SIZE = 20mm TA = -55oC TO +85oC 130 TO 320VM(AC) RATING 2,000 MAXIMUM PEAK VOLTAGE (V) MAXIMUM PEAK VOLTAGE (V) 2,000 10-2 10-1 100 101 102 PEAK AMPERES (A) 103 104 FIGURE 4. MAXIMUM CLAMPING VOLTAGE FOR V130LA20C TO V320LA40C MODEL SIZE = 20mm TA = -55oC TO +85oC 130 TO 300VM(AC) RATING V300LA40CX745 V275LA40CX680 V250LA40CX620 V230LA40CX570 V175LA20CX425 V150LA20CX360 V140LA20CX340 V130LA20CX325 100 10-3 10-2 10-1 100 101 102 PEAK AMPERES (A) 103 104 FIGURE 5. MAXIMUM CLAMPING VOLTAGE FOR V130LA20CX325 TO V300LACX745 Pulse Rating Curves 10,000 RATED PEAK SURGE CURRENT (A) 2 10,000 MODEL SIZE = 14mm TA = -55oC TO +85oC 130 TO 320VM(AC) RATING RATED PEAK SURGE CURRENT (A) 1 10 102 1,000 103 104 100 INDEFINITE SURGE CAPABILITY 10 1 10 102 100 1,000 SURGE IMPULSE DURATION (s) 10,000 FIGURE 6. REPETITIVE SURGE CAPABILITY FOR V130LA10C TO V320LA20C 2 MODEL SIZE = 20mm TA = -55oC TO +85oC 130 TO 320VM(AC) RATING 103 1,000 104 100 INDEFINITE SURGE CAPABILITY 10 1 10 1 10 100 1,000 SURGE IMPULSE DURATION (s) 10,000 FIGURE 7. REPETITIVE SURGE CAPABILITY FOR V130LA20C TO V320LA40C 4-29 "C" III Series Tape and Reel Specification Tape and Reel Data * Conforms to ANSI and EIA Specifications * Can be supplied to IEC publication 286-2 * Radial devices on tape and reel are supplied with either crimped leads, straight leads, or under-crimped leads. Tape and Reel Ordering Information * Crimped leads are standard on LA types supplied in tape and reel and are denoted by the model letter "T". Also, in tape and reel, model letter "S" denotes straight leads and letter "U" denotes special under-crimped leads. Example: STANDARD MODEL V130LA20C CRIMPED LEADS STRAIGHT LEADS UNDER CRIMP LEADS V130LT20C V130LS20C V130LU20C Shipping Quantity DEVICE SIZE QUANTITY PER REEL "T" REEL "S" REEL "U" REEL 14mm 500 500 500 20mm 500 500 500 Package Outline Dimensions MODEL SIZE SYMBOL DESCRIPTION P Pitch of Component 14mm 20mm 25.4 1.0 P0 Feed Hole Pitch 12.7 0.2 P1 Feed Hole Center to Pitch 2.60 0.7 P2 Hole Center to Component Center 6.35 1.0 F Lead to Lead Distance 7.50 0.8 h Component Alignment 2.00 Max W Tape Width W0 Hold Down Tape Width W1 Hole Position W2 Hold Down Tape Position 0.5 Max H Height From Tape Center To Component Base H0 Seating Plane Height H1 Component Height D0 Feed Hole Diameter VARISTOR MODEL SIZE 14mm 18.25 0.75 20mm SYMBOL MIN MAX MIN MAX A 13.5 (0.531) 20 (0.787) 17.5 (0.689) 26.5 (1.043) OD 13.5 (0.531) 17 (0.669) 17.5 (0.689) 23 (0.906) 19.0 1.0 e 6.5 (0.256) 8.5 (0.335) 6.5 (0.256) 8.5 (0.335) 16.0 0.5 e1 1.5 (0.059) 3.5 (0.138) 1.5 (0.059) 3.5 (0.138) E - 5.6 (0.220) - 5.6 (0.220) Ob 0.76 (0.030) 0.86 (0.034) 0.76 (0.030) 0.86 (0.034) 6.00 0.3 12.0 0.3 9.125 0.625 40 Max 46.5 Max 4.0 0.2 t Total Tape Thickness 0.7 0.2 L Length of Clipped Lead 12.0 Max p Component Alignment 3o Max Dimensions are in millimeters (inches) NOTE: 10mm lead spacing also available. See additional lead style options. 4-30 "C" III Series Additional Lead Style Options The Origins of Surge Overvoltages Radial lead types can be supplied with combination preformed crimp and trimmed leads. This option is supplied to the dimensions shown below. There are a wide variety of transient overvoltage environments, each with radically different levels of exposure. Transients may be caused by lightning, which can inject very high currents into the electrical system, or by switching transients. Lightning strikes usually occur to the primary transmission lines with resulting coupling to the secondary line through mutual inductive or capacitive coupling. Even a lightning hit that misses the primary AC line can induce substantial voltage onto the primary conductors, triggering lightning arresters and thus creating transients. VARISTOR MODEL SIZE 14mm 20mm SYMBOL MIN MAX MIN MAX A - 24.5 (0.96) - 31 (1.22) LTRIM 2.41 (0.095) 4.69 (0.185) 2.41 (0.095) 4.69 (0.185) Switching transients, while of a lower magnitude than lightning, occur more frequently and thus are of a greater threat to the AC system. Switching transients may result from fuse blowing, capacitor bank switching, fault clearing or grid switching. NOTE: Dimensions are in millimeters (inches) Field studies and laboratory investigation of residential and industrial low power AC voltage systems have shown that the amplitude of a transient is proportional to the rate of its occurrence, i.e. lower magnitude transients occur most often. Governing bodies, in particular IEC, UL, IEEE and ANSI have established guidelines on the transient environment one may expect to encounter in a low voltage AC power system. Table 1 reflects the surge voltages and currents deemed to represent the indoor environment. *Seating plane interpretation per IEC-717 LOCATION CATEGORY * To order this crimped and trimmed lead style, the standard radial type model number "LA" is changed to the model number "LC". This option is supplied in bulk only. Example: STANDARD MODEL ORDER AS V130LA20C V130LC20C * For 10 1mm lead spacing on 20mm units only; append standard model numbers by adding "X10" suffix. Example: STANDARD MODEL ORDER AS V130LA20C V130LA20CX10 * For other lead style variations to the above, please contact Harris Semiconductor Power Marketing 4-31 TRANSIENT WAVEFORM/ MAGNITUDE A Long Branch Circuits and Outlets 0.5s 100kHz 6kV 200A B Major Feeders and Short Branch Circuits 1.2/50s 8/20s 6kV 3kA 0.5s 100kHz 6kV 500A "C" III Series "C" III MOV Series The new "C" III series of Harris radial MOVs represent the third generation of improvements in device performance and characteristics. The technology effort involved in the development of this new series concentrated on extending the existing performance and capability of the Harris second generation of metal oxide varistors. The characteristics of greatest importance for a metal oxide varistor in an AC surge environment are the peak current, energy handling, repetitive surge and temporary over-voltage capabilities. The focus of the design effort was on improving these characteristics and therefore offering the maximum protection presently available to the end user. The new "C" III series are designed to survive the harsh environments of the AC low-power indoor environment. Their much improved surge withstand capability is well in excess of the transients expected in the AC mains environment. Further design rules for the development of the "C" III series included considerations of the expected steady state operating conditions and the repetitive surge environment. Investigation of the AC low-power indoor environment show that most transients occur where the power enters the building and at major feeders and short branch circuits. Surges recorded at this service entrance, location Category B from C62.41-1992, may be both oscillatory and unidirectional in nature. The typical "lightning surge" has been established as a 1.2/50s voltage wave and a 8/20s current wave. A short circuit current of 3000A and open circuit voltage 6000V are the expected worst case transients at this location. TEST Surge Current REFERENCE STANDARD TEST CONDITIONS TEST RESULTS The further into the facility one goes, the lower the magnitude of the transients encountered. ANSI/IEEE C62.41 differentiates between the service entrance and the interior of a facility. Per this specification, the internal location or long branch circuits and outlets are classified as Location Category A. The transients encountered here have oscillatory waveshapes with frequency ranges from 5kHz to 500kHz; with 100kHz deemed most common. Transients of the magnitude of 500A are expected in this location. Reliability Performance of "C" III Series The electrical ratings of the "C" III series of MOVs are conservatively stated. Samples of these devices have been tested under additional stresses, over and above those called out in the datasheet. The results of this testing show an enhanced device performance. The series of stress tests to which the units were subjected are a combination of electrical, environmental and mechanical tests. A summary of the reliability tests performed on the "C" III series are described in Table 2 AC Bias Reliability The "C" III series of metal oxide varistors was designed for use on the AC line. The varistor is connected across the AC line and is biased with a constant amplitude sinusoidal voltage. It should be noted that the definition of failure is a shift in the nominal varistor voltage (VN) exceeding 10%. Although this type of varistor is still functioning normally after this magnitude of shift, devices at the lower extremities of VN tolerance will begin to dissipate more power. UL 1449 IEEE/ANSI C62.41 9000A (8/20s) 1 Pulse 0/165 IEC 1051 7000A (8/20s) 2 Pulses 0/105 3000A (8/20s) 20 Pulses 0/75 750A (8/20s) 120 Pulses 0/65 Transient Surge Current/Energy Capability The transient surge rating serves as an excellent figure of merit for the "C" III suppressor. This inherent surge handling capability is one of the new "C" III suppressor's best features. The enhanced surge absorption capability results from improved process uniformity and enhanced construction. The homogeneity of the raw material powder and improved control over the sintering and assembly processes are contributing factors to this improvement. Surge Energy UL 1449 IEEE/ANSI C62.41 IEC 1051 90J (2ms) 1 Pulse 0/125 Operating Life Mil-Std-202 Method 204D 125oC, 1000 Hours, Rated Bias Voltage 0/180 Temporary Overvoltage N/A 120% Maximum Rated Varistor Voltage For 5 minutes 0/70 Because of this possibility, an extensive series of statistically designed tests were performed to determine the reliability of the "C" III type of varistor under AC bias combined with high levels of temperature stress. To date, this test has generated over 50,000 device hours of operation at a temperature of +125oC, although only rated at +85oC. Changes in the nominal varistor voltage, measured at 1mA, of less than 2% have been recorded (Figure 8). In the low power AC mains environment, industry governing bodies (UL, IEC, NEMA and IEEE) all suggest that the worst case surge occurrence will be 3kA. Such a transient event may occur up to five times over the equipment life time (approximately 10 years). While the occurrences of five 3 4-32 "C" III Series Terms and Descriptions Rated AC Voltage (VM(AC)RMS) This is the maximum continuous sinusoidal voltage which may be applied to the MOV. This voltage may be applied at any temperature up to the maximum operating temperature of +85oC. Maximum Non-Repetitive Surge Current (ITM) This is the maximum peak current which may be applied for an 8/20s impulse, with rated line voltage also applied, without causing device failure. (See Figure 2) 300 V130LA20C VNOM AT 1mA (V) As a measure of the inherent device capability, samples of the 20mm V130LA20C devices were subjected to a worst case repetitive transient surges test. After 100 pulses, each of 3kA, there was negligible change in the device characteristics. Changes in the clamping voltage, measured at 100 amps, of less than 3% were recorded (Figure 9). Samples of the 14mm Series V175LA20C were subjected to repetitive surge occurrences of 750A. Again, there was negligible changes in any of the device characteristics after 250 pulses (Figure 10). In both cases the inherent device capability is far in excess of the expected worst case scenario. . 250 200 150 100 0 100 200 300 400 500 600 700 TIME (HOURS) 800 900 1000 1100 FIGURE 8. HIGH TEMPERATURE OPERATING LIFE 125oC FOR 1000 HOURS AT RATED BIAS CLAMPING VOLTAGE AT 3kA kiloamps transients is the required capability, the conservatively rated, repetitive surge current for the "C" III series is 20 pulses for the 20mm units and 10 pulses for the 14mm series. 500 450 400 350 (RATED FOR 20 SURGES) 300 0 This is the voltage at which the device changes from the off state to the on state and enters its conduction mode of operation. This voltage is characterized at the 1mA point and has specified minimum and maximum voltage levels. Clamping Voltage (VC) This is the peak voltage appearing across the MOV when measured at conditions of specified pulse current amplitude and specified waveform (8/20s) 4-33 CLAMPING VOLTAGE AT 750A Nominal Voltage (VN(DC)) 10 20 30 40 50 60 70 80 NUMBER OF SURGES 90 100 110 120 FIGURE 9. TYPICAL REPETITIVE SURGE CURRENT CAPABILITY OF "C" III SERIES MOVs Maximum Non-Repetitive Surge Energy (WTM) This is the maximum rated transient energy which may be dissipated for a single current pulse at a specified impulse and duration (2ms), with the rated VRMS applied, without causing device failure. V130LA20C 3kA (8/20s) 600 V175LA20C 750A (8/20s) 550 500 450 400 350 (RATED FOR 80 SURGES) 300 0 50 100 150 200 NUMBER OF SURGES 250 300 FIGURE 10. TYPICAL REPETITIVE SURGE CURRENT CAPABILITY OF "C" III SERIES MOVs