4537491 HOLMES (CARL ) co SECTION 1. COMPONENTS 88327872 coaoves 3 of Silicon Diode Rectifiers 94D 00029 D 7-o/-2r Litetehdrnrtentctannneahathntntheeiaehileantenmntnentaltletwdinni incline stimmetn i e Rectifier diodes are used to convert alternating current into direct current. Silicon is the preferred material for rectifier diodes because of its efficiency and also because it does not weaken with use. High-current rectifier diodes are used in a wide variety of applications ranging from plating, anodizing, and welding to elevator operation and specialized power supplies. The schematic symbol for a diode is: Note: The polarity arrow ALSO SHOWN points to the cathode. >}- Diodes come in several different packages, including some stud- mounted packages with standard polarity and others with reverse polarity. Other diodes, such as flat packs, have only one polarity. To set polarity with these devices, simply point the polarity arrow toward the positive side of the circuit. The following are examples of the types of diodes available: POLARITY ARROW ANODE CATHODE CATHODE ANODE AXIAL ANODE + CATHODE LEAD DIODES ANODE CATHODE + i] Carl E. Holmes Co. CATHODE ANODE * STUD MOUNTED DIODES ANODE CATHODE _ REVERSE POLARITY FLAT PACK ANODE CATHODE DIODE The key characteristic of all diodes is that they conduct current only in one direction. In the opposite direction, they appear as open circuits (except for minimal leakage). Diodes conduct when they are forward biased. That is, when their anodes are positive with respect to their cathodes. And they block the flow of current when they are reverse biased: When their anodes are negative with respect to their cathodes. Note: The cathode end of adiode is often called the positive end because in simple rectifier circuits the direct current that is developed at this point is positive with respect to ground. ANODE CATHODE Ammeter shows current flowing <4 I| FORWARD BIAS PROTECTIVE RESISTOR ANODE CATHODE Ammeter shows no current flowing REVERSE BIAS OR MORE SIMPLY + - _}_____- CONDUCTING - + _____-- BLOCKING Because of their ability to change conductivity as polarity changes, diodes are capable of producing pulsating direct current from alternating current sources to 1000 Hz. Fast turn off diodes and SCRs can be obtained for up to 20 KHz. + AC f\ f\ +t SOURCE = PULSATING DC Two characteristics are particularly important when diodes are being selected for use in a circuit: 1. Iftmaxy The safe maximum forward current that can be passed through the diode when it is conducting. If this value is exceeded for more than about 8 milliseconds (surge current), the - diode may be destroyed. Therefore it is important to use diodes with maximum forward current ratings higher than the maximum current expected in the circuit. (Typically, diodes with maximum forward current ratings of one and one-half to two times normal circuit conditions are selected depending on the cooling available, Note that the margin hinges on the maximum temperature rating of the diode.) 2. PRVThepeak reverse voltage is the maximum voltage which may safely be impressed across a diode in the reverse bias direction. Beyond this value, a diode begins to conduct current heavily and it can be destroyed. A diode selected for a specific application should have a peak reverse voltage well in excess of the maximum value expected. (Typically, diodes with peak reverse voltage ratings two to three times normal circuit conditions are selected.) Peak reverse voltage is also known as peak inverse voltage (PIV) and reverse breakdown voltage (Vbr). Diode Testing An ohmmeter can be used to identify the anode and cathode of an unmarked diode and for testing diodes. For such tests, it is good practice to set the ohmmeter to a high range (R x 1,000 or R x 10,000). Typical ohmmeters, such as VOM's, usually connect the red or plus lead to the negative side of the internal battery 107 North Avenue 64 e Los Angeles, California 90042 e (213) 256-22554537491 HOLMES CCARL &) CO 84D 00030 D J -or-2z! for ohms testing. (You can check this DIODE ORDERING INSTRUCTIONS with a known good diode or with a . voltmeter.) Thus, the following diagram There are a few facts that you should polarity. shows a typical VOM test of a diode. collect before your call. (If you are 5. If possible, determine the CEHCO unable to find some of this information, part number from the accompanying Low resistance call and we will be glad to assist you.) charts and illustrations (or call and we /* indicates current 1, Determine the physical size of the will help you). | / J (from the internal battery) diode you need. (Use the illustrations in is flowing through the diode. | this section as a guide to making Notes: Rx 10K measurements.) 1. When the maximum forward @) 2. Determine the direct current current (amperage) of a diode is COM va output of the diode. (If you do not know unknown, measure the stud or flat-pack 7 q how to do this, check with CEHCO for size and select the same-size diode with BLACK RED assistance.) the highest maximum forward current 3. Determine the number of devices rating. + - required (the number of diodes that are 2. When the peak reverse voltage of wired so they work together). a diode is unknown, multiply the 4. Determine the direction of the transformer secondary voltage or the High resistance polarity sign (see the discussion earlier direct current (dc) for the circuit times 2.5 < indicates only in this section) and ascertain whether to obtain an appropriate peak reverse eae trough the diode has standard or reverse voltage rating. Rx 10K the diode. @) fe Note: Voltage codes are found on the device. e. STANDARD VOLTAGE CODES ON DEVICES RED BLACK PEAK WEST REPETITIVE CEHCO SIEMENS IR GE AND NATIONAL - * REV. VOLT PSI BATTERY 100 10 10 10 A 1 A 200 20 20 20 B 2 B cou LY | circuit 300 30 30 30 Cc 3 Cc MW Ohmmeter 400 40 40 40 D 4 D 500 50 50 50 E 5 E 600 60 60 60 M 6 M 700 70 70 70 Ss 7 Ss The ratio of back-to-front resistance 800 80 80 80 N 8 N for most diodes should be around 1,000 900 90 90 90 T 9 T to one. However, this ratio may not hold 1000 100 100 100 P 10 P if the diode is connected in a circuit. In 1200 120 120 120 PB 12 PB the latter case, a ratio of 10 to 1 usually 1400 140 140 140 PD 14 PD indicates that the diode is working 1600 160 160 160 PM 16 PM properly. But if you are in doubt, disconnect one end of the diode to isolate it from the circuit before taking CEHCO DIODES test readings. SERIES AMPS AVG | VOLTAGE RANG Note: CEHCO manufactures a diode AXIAL ois 10 400 - 1000 V and SCR tester (see section 3) that LEAD = 038 3.0 4100 - 1000 V comes complete with instructions for testing. Ask for part number T100. > 225 22R 22 100 - 1200 V ee 45S 45R 45 100 - 1200 V CEHCO Diode Nomenclature sTuD 85S 885A 85 100 - 1200 V Along with an identifying number, MOUNT 1505 150R 150 100 - 1200 V CEHCO diode part numbers include an 3800S = 300R 300 100 - 600 V S for standard polarity or an R for 3801S 301R 300 100 - 2400 V reverse polarity. Other letters following 4005 400R 400 100 - 2400 V the polarity designation, such as E, F, G, 500S__500R 500 100 - 2400 V and H, refer to package size (see the 600SE 430 800 - 2000 V diode dimension diagrams in this FLAT 1400SG 1150 200 - 2000 V section). PACKS 2100SH 1700 200 - 2000 V 2500SH 2160 200 - 2000 V S - Standard Polarity Note: It is a good practice to protect rectified circuits with nonpolar surge suppres- R - Reverse Polarity Or aoe the omer secondary (see the section on surge suppressors for 2 WaRI] Carl E. Holmes Co. 107 North Avenue 64 e Los Angeles, California 90042 e (213) 256-2255 a4 pe ffysaz4s2 coooo3z0 o ,HOLMES {CARL E} CO ayy Bous37usa oooo031 i a DIODE DIMENSION DIAGRAMS 3/8-24 UNF-2A 6_9s Dimensions in accordance with JEDEC Outline DO-8 375 = 3/4-16 UNF-2AS__"r Dimensions In accordance with JEDEC Outline DO-9 375 = 828 3/4-16 UNF-2A@___"t Dimenslons in accordance with JEDEC Outline DO-9 SERIES SE -15 DIA .08 DEEP = 56 2} .76--| | 65 1.46-41 Dimensions in accordance with JEDEC Outline 00-200AB SERIES SG +15 DIA .08 DEEP Pe = 1.07 4 b1.35 } | es aI 03 SERIES SH -15 DIA 08 DEEP SERIES 01 = .250 SERIES 22 SERIES 45 SERIES 85 1.0 1.0 ter 203 281 281 118 DIA__4.032 DIA .150 DIA MAX .150 DIA MAX .093 DIA 437 8 . 1.0 MAX 1.0 MAX ERIE ACROSS s Ries 8 FLATS DO) 437 | | 682 | 375 mt ACROSS } ACROSS } 750 750 10-32 UNF-2A 437 FLATS ag? FLATS a7 j__t 1/4-20 UNF-2A 1/4-20 UNF-2A WA Dimensions in accordance Dimensions in accordance Dimensions In accordance .270 DIA .050 DIA with JEDEC Outline DO-4 with JEDEC Outline DO-5 with JEDEC Outline DO-5 SERIES 300 and 400 SERIES 301 SERIES 500 755 it eh 350 DIA =F SERIES 150 .350 DIA~{7.453 I -500 .412 DIA , .281 pia 70 5.702 NY \ N 5.975 1.10 1.10 N 4.062 1.260 MAX 1.250 2-250 MAX ACROSS =| ACROSS 2.125 MAX FLATS 12 MAX FLATS HH. 25 MAX 78 LLL 1.470 30 1.687 r ACROSS t FLATS \ 1.639 AAG 7 mn 3/4-16 UNF-2A Dimensions in accordance with JEDEC Outline B-8 Gi Carl E. Holmes Co. 107 North Avenue 64 e Los Angeles, California 90042 e (213) 256-2255 Note: Dimensions in inches. 1.0934537491 HOLMES CCARL E) CO 4D 00032 D T-or-2t RECTIFIERS T4 DEM 4537491 o000032 3 1 UNIT SERIES 01 03 22 45 85 150 300 | 301 400 500 | GOOSE |1400SG |2100SH | 2500SH Rectifiers ELECTRICAL CHARACTERISTICS Maximum average forward * current single phase halfwave 01 03 22 45 85 150 | 300] 300) 400 500} 430] 1,150) 1,700| 2,160 de rating at 125C case temp. teimaxy (also known as lowaaxy) Maximum surge current peak 60 150 250 700 | 1,500} 2,100 | 5,000 | 6,500 | 7,800 | 8,000} 5,500; 8,000; 22K 22K one cycle surge @ 8.3 ms. Peak forward voltag drop at 1.00 | 1.00 | 1.20 | 1.15] 1.15) 1.40] 140] 1.62] 1.62 1.45| 1.50] 1.00] 1.00} 1.00 25 At noted amps. Vv 30 90 200 200 300 300} 400 500 500 500} 2,500; 2,500 Rated peak reverse voltage 100 V to (* 800V min) 1,000 11,000 | 1,600 | 1,600 | 1,600] 1,600 600 |*2,400 | 2,400 |*2,400} 3,000! 2,000 | 2,000] 2,000 PRV (also kriown as PIV or V,,.) Maximum {?t (Less than 8 ms.) - - 250 | 2,100 | 9.300} 18,200 | 100K | 160K | 340K] 455K | 125K] 265K 2,000K |2,000K amps.? per second THERMAL CHARACTERISTICS Storage Temperature 0 C -65 | -65/| -65 - ~65| -65| -65| -40| -40| -40| -40} ~40| -40|} -40 +185 14185 | +200 | +200} +200] +200 | +200 | +200} +200) +200] +150] +190] +190] +190 Operating temperature range -65 | -65 |] -65 | 65 -65| -65] -65] -40;} -40 -40} -40] -40/ -40; ~-40 Junction @C) +175 14175 | +190 | +190] +190] +190 | +200 | +200 | +200] +200} +150) +190} +150) +190 Impedence (c/w) junction - - 2.00 | 1.25 .60 35 08 .08 .04 04 09 06 03 .03 to case max. MECHANICAL CHARACTERISTICS Torque inch Ibs. max. - - 30 75 30 125 325 325 | 325 325; - - - - Thread size - - 10-32 | 44-28 | %4-28)**%-24 | %-16 | 44-16 | %4-16| %4-16) - - - - Mounting force Ibs. - - - - - - - - - 1,100] 2,200] 4,400} 4,400 ** 2"-20 adaptor available. Rectifier available in both forward and reverse polarity. S. = Positive Stud R = Negative Stud Voltage Code 10 20 30 40 50 60 70 80 90 100 120 140 160 100V 200V 300V 400V 500V 600V 700V 8s00V 900V 1000V 1200V 1400V 1600V EXAMPLE: Series Polarity Voitage 150 R 60 150 amp Reverse Polarity 600V. Ki] Carl E. Holmes C Oo. e 107 North Avenue 64 e Los Angeles, California 90042 e (213) 256-2255ay > Wusazy9a cooooaa sf o zene, RECTIFIER DESIGN FACTORS HOLMES tCARL E} CO _ 2 3 4 5 6 7 8 FORM FACTOR Cap. K Conversion Res. Motor Ripple (Ckt. Efficiency Circuit Diagram | ind. Batt. fi/ft % Constant | fa/IL lefle e/le (%) Half-Wave Fig. A 2.22 1.0 1 12.5 1 1.0 1.57 1.57 40.6 SINGLE Bri 2 0.785 | 1.44 81,2 PHASE tidge Fig. B 1.14 0.8 2 2 0.5 Center-Tap Fig. C 1.11 0.8 2 52 1 0.5 0.785 0.785 81.2 Half-Wave (Wye) | Fig. D 0.85 0.85 3 20 1 0.333 0.578 0.578 97 PHnoe Bridge Fig. E 0.74 0.74 6 4.5 2 0.333 0.582 0.820 99.5 Double-Wye Fig. F 0.85 0.85 6 4.5 2 0.167 0.290 0.290 99.5 Star or CT Fig. G 0.74 0.74 6 4.5 1 0.167 0.409 0.409 99.5 Wye-Delta Parallel Fig. H 0.72 0.72 12 2 2 0.167 0.290 0.408 99.5 six Output PHASE Wye-Delta Series Fig. J 0.36 0.36 12 2 2 0.333 {| 0.582 | 0.829 99.5 Output 1. Form Factor - Ratio of rms to DC voltage across load. 2. fi/ti - Ratio of ripple frequency to input frequency. 3. Ripple % - Ripple components of output voltage. Note: For additional design information see Appendix A, page 36. 4. K (Ckt. Constant) - Number of series arms during conduction cycle. 5. la/lL - Ratio of DC current per arm to total load current. 6. lo/IL - Ratio of rms current per arm to total load current. 7. Ic/lL - Ratio of rms transformer secondary current to total DC foad current. 8. Conversion Efficiency does not include rectifier losses. RECTIFIER DESIGN DIAGRAMS i wae: wey She ri Fig. A Fig. B Fig, C Fig. D Fig. E wT wT TRANSFORMER WINDINGS y Fig. F Fig. J - Fig. H Rae!) Carl E. Holmes Co. 107 North Avenue 64 e Los Angeles, California 90042 e (213) 256-2255