SEFUSE TM THERMAL CUTOFF 8th Edition Cutaway View of SEFUSETM SF Type SF Type SEFUSE TM Contents Introduction ..................................................................................................................................... 4 Features ............................................................................................................................................ 4 Applications ..................................................................................................................................... 4 Product Types .................................................................................................................................. 5 Operating Principle ......................................................................................................................... 6 Drawings, Dimensions and Marking ............................................................................................. 7 Standard Ratings ............................................................................................................................. 8 Performance Data .......................................................................................................................... 11 Lead Cutting and Taping ............................................................................................................... 15 Cautions ......................................................................................................................................... 16 Application Examples ................................................................................................................... 21 Series Rated Current Rated Functioning Temperature Page SF / E 10 Aa.c. 73 C to 240 C 8 SF / Y 15 Aa.c. 73 C to 24C C 8 SM / A 2 Aa.c. 70 C to 187 C 9 SM / B 1 Aa.c. 100 C to 150 C 9 SM / G 0.5 Aa.c. 100 C to 150 C 9 Select optimum series according to temperature and electrical ratings. Please be sure to read the "Cautions" on pages 16 through 19 before using. 3 Introduction NEC's SEFUSETM is a compact and reliable thermal cutoff designed to protect domestic electrical appliances and industrial electrical equipment from fire. Cutoff occurs and an electrical circuit opens when ambient temperature increases to an abnormal level. Two NEC SEFUSE types are available. The SF type uses an organic thermosensitive material as the thermal pellet and its operating temperature range is 73 C to 240 C. The SM type uses a fusible alloy and has an operating range of 70 C to 187 C. SEFUSE is manufactured in Japan and thailand, and both factories are ceritified by the International Standards Organization (lSO) for the ISO9001 quality standard. The factory in Japan is certified for the ISO 14001 environmental management system too. Features Compact, durable, and reliable by resin-sealed construction One shot operation Excellently sensitive to abnomal temperature rise and high accuracy in operation Stable and precise operation Wide choice of types to suit the application (SF or SM) Meets many international safety standards Applications Electric heaters, electric irons, hair dryers, electric blankets Air conditioners, compressors, washing machines, electric fans, ventilation fans, electric pencil sharpeners, electric sewing machines, copy machines, various motors Color televisions, LCD televisions, stereo equipment, Iamps, fluorescent lamps, electric shavers, video and audio cassette recorders, various transformers, AC adaptor, charger, Battery packs Rice cookers, microwave ovens, electric refrigerators, electric water pots, toasters, electric pans, coffee makers, juicers, dish dryers Gas boilers, gas heaters, oil heaters, cameras, telephone switching (PBX) equipment Safety standards Japan UL CSA VDE BEAB Electrical Appliance and Material Control Law of Japan Underwriters Laboratories Inc. (U. S. A.) Canadian Standards Association Verband Deutscher Elektrotechniker e.V. (F. R. G.) British Electrotechnical Approvals Board 4 SEFUSE TM Product Types The SF type uses an organic thermosensitive pellet inside a metal case. It features a large cutoff (rated) current of 10 A or 15 A. The SM type uses a fusible alloy inside a ceramic case. It has a cutoff(rated)current of 0.5 A, 1 A or 2 A. Because of its insulated case, the SM type can be attached directly where temperature detection is required. SF Type SM Type 5 Operating Principle SF Type THE SF type contains a sliding contact, springs, and a thermal pellet inside a metal case. When spring B is compressed, firm contact between lead A and the sliding contact occurs. This presses two disks against the sliding contact and the thermal pellet. At normal temperatures, current flows from lead A to the sliding contact and then through the metal case to lead B. When the ambient temperature rises to the SEFUSE operating temperature, the heat transferred through the metal case melts the thermal pellet. When the thermal pellet melts, springs A and B expand, moving the disk and sliding the contact away from lead A. The electrical circuit is opened by breaking contact between the sliding contact and lead A. Before Operation Ceramic Spring B After Operation Metal Case Thermal Pellet ,, ,, Sealing Compound Lead A Ceramic Pipe Spring A Sliding Contact Disks Thermal Pellet ,,, ,,, Spring B Lead B Metal Case Sliding Contact Spring A Disks SM Type In the SM type, Ieads A and B are connected by a conductive thermal pellet (fusible alloy). The current flows directly from one lead to the other. The fusible alloy is coated with a special flux. When ambient temperature rises to the SEFUSE operating temperature, the fusible alloy melts and condenses into a drop around the end of each lead because of surface tension and the coating of special flux. The electrical circuit then opens. Before Operation Sealing Compound Lead Ceramic Case Fusible Alloy ,,, Flux 6 After Operation Sealing Compound Fusible Alloy Lead Lead , Flux , Lead SEFUSE TM Drawings Dimensions, and Marking SF Type Unit : mm 11 20(35) 1.0 4.2 SF/E Series 1.0 MARKING Factory Code SEFUSE SF139E T f 1 4 2C 10A 250V ~ MITI Approved Mark 35 66(81) Brand Name Part Number Production Control No. Rated Functioning Temperature Rated Current Rated Voltage Factory Code represents the factory location as shown below. Japan : none, Thailand : B Unit : mm MARKING SEFUSE SF139Y 1.3 4.2 SF/Y Series 1.3 Maker Mark 11 20(35) MITI Approved Mark 35 66(81) 139C 15A 250V Brand Name Part Number Production Control No. Rated Functioning Temperature Rated Current Rated Voltage Note: The dimensions for long lead devices are in parentheses. SM Type Unit : mm 38(68) 9 MARKING 0.6 2.5 SM/A, SM/B Series 0.6 38(68) SEFUSE Brand Name SM126A0 Part Number Production Control No. Rated Functioning Temperature 85(145) 0.53 0.53 2.0 SM/A MITI Approved Mark Rated Current 39.5(69.5) 6 T f 1 3 1 C 2A 250V ~ Rated Voltage 39.5(69.5) 85(145) SM/B SM/G Series 40(70) 5 85(145) 0.53 1.6 0.53 40(70) MARKING MITI Approved Mark Production Control No. Rated Current SEFUSE Brand Name 110 G0 Part Number Tf 115C 0.5 A 2 5 0 V ~ Rated Functioning Temperature Rated Voltage Note: The dimensions for long lead devices are in parentheses. 7 Standard Ratings SF Type SF/E Series Part 1) Rated Functioning Operating Temperature Number Temperature TF, Tf SF 70E 73 C 702 C SF 76E 77 C 76 204 C 3 1 TH Th TC 45 C 150 C 51 C 150 C TM Tm Safety Standard Rated Rated Current Voltage UL CSA VDE BEAB 5) SF 91E 94 C 91 2 C 66 C 150 C SF 96E 99 C 962 C 71 C 150 C SF109E 113 C 109 231 C 84 C 150 C SF119E 121 C 1192 C 94 C 150 C SF129E 133 C 1292 C 104 C 159 C 10 A 250 V SF139E 142 C 1392 C 114 C 159 C (AC) (AC) SF152E 157 C 1522 C 127 C 172 C SF169E 172 C 169 213 C 144 C 189 C SF188E 192 C 188 231 C 164 C 300 C SF214E 216 C 214 213 C 189 C 350 C SF226E 227 C 226 213 C 190 C SF240E 240 C 2372 C 190 C 2) 3) E71747 4) LR 52330 6778.2 -1171 -0002 6778.2 -4510 -1008 2) 350 C made in Japan made in Thailand 33-312 33-835 33-331 33-834 33-332 33-833 33-333 33-832 33-334 33-831 33-335 33-830 C0632 33-336 33-886 33-549 33-827 33-354 33-828 Note : 1) Part numbers are for standard lead devices. For long leads, add the number "-1" at the end of part number. 2) The maximum temperature limit of SF226E is partially approved as shown below. TM.Tm UL CSA VDE BEAB SF226E 240C 330C 300C 300C * Under application to increase to over 300C 3) The additional electrical ratings are recognized by UL and CSA as follows. UL : 277 Vac / 15 Aac (Resistive), 240 Vac / 15 Aac (Resistive), 120 Vac / 15 Aac (Resistive, Inductive) CSA : 250 Vac max. / 15 Aac max. (Resistive, Inductive) 4) SF169E, SF188E, SF214E, SF226E and SF240E are also UL-recognized of optional CH-rating (Conductive Heat Aging Test). 5) The VDE recognized file number had been changed in February 1998. The number in parentheses are previous file number. SF/Y Series Part Number 1) Rated Functioning Temperature Operating Temperature Rated Current Rated Voltage SF 70Y 73 C 70 2 C SF 76Y 77 C 76 204 C SF 91Y 94 C 91 231 C SF 96Y 99 C 96 2 C SF109Y 113 C 109 231 C SF119Y 121 C 119 2 C SF129Y 133 C 129 2 C SF139Y 142 C 139 2 C SF152Y 157 C 152 2 C SF169Y 172 C 169 213 C 33-335 SF188Y 192 C 188 231 C 33-336 SF214Y 216 C 214 213 C 33-549 SF226Y 227 C 226 213 C SF240Y 240 C 237 2 C 33-312 33-331 33-332 33-333 15 A (AC) 250 V (AC) Note : 1) Part numbers are for standard lead devices. For long leads, add the number "-1" at the end of part number. 8 Safety Standard 33-334 33-354 SEFUSE TM SM Type #) The VDE recognized file number had been changed in February 1998. The number in parentheses are previous file number. SM/A Series Part 1) Rated Functioning Operating Temperature Number Temperature TF, Tf SM065A0 70 C 65 2 C TH Th TC 40 C 80 C TM Tm Rated Rated Current Voltage Safety Standard UL CSA VDE BEAB 33-528 #) SM095A0 100 C 95 250 C 65 C 115 C SM110A0 115 C 110 2 C 80 C 125 C SM126A0 131 C 126 2 C 96 C 140 C 2A 250 V SM130A0 135 C 130 2 C 100 C 145 C (AC) (AC) SM145A0 150 C 145 2 C 115 C 160 C SM164A0 169 C 164 232 C 133 C 180 C SM182A0 187 C 182 2 C 152 C 195 C 6778.2 -1171 -0001 E71747 LR52330 33-466 33-472 C0600 ( ) 6778.2 -4510 -1007 33-467 33-468 33-470 33-556 Note : 1) Part numbers are for standard devices. For long leads, change the last number from 0 to 1. SM/B Series TH Th TC Part 1) Rated Functioning Operating Temperature Number Temperature TF, Tf SM095B0 100 C 95250 C 65 C 115 C SM110B0 115 C 1102 C 80 C 125 C SM126B0 131 C 1262 C 96 C 140 C SM130B0 135 C 1302 C 100 C 145 C SM145B0 150 C 1452 C 115 C 160 C TM Tm Rated Rated Current Voltage Safety Standard UL CSA VDE BEAB #) 1A 250 V (AC) (AC) E71747 LR52330 6778.2 -1171 -0004 6778.2 -4510 -1009 33-466 33-472 C0557 ( ) 33-467 33-468 Note : 1) Part numbers are for standard devices. For long leads, change the last number from 0 to 1. Tm of SM145B for CSA is 155 C SM/G Series Part 1) Rated Functioning Operating Temperature Number Temperature TF, Tf SM095G0 100 C 95250 C TH Th TC 65 C 115 C SM110G0 115 C 1102 C 80 C 125 C SM126G0 131 C 1262 C 96 C 140 C SM130G0 135 C 1302 C 100 C 145 C SM145G0 150 C 1452 C 115 C 155 C TM Tm Rated Rated Current Voltage Safety Standard UL CSA VDE BEAB #) 2) 2) 0.5 A 250 V (AC) (AC) E71747 LR52330 6778.2 -1171 -0003 6778.2 -4510 -1005 ( ) 33-466 33-472 C0743 33-467 33-468 Note : 1) Part numbers are for standard lead devices. For long leads, change the last number from 0 to 1. 2) The additional electrical ratings are recognized by UL as follows. SM095G : DC 50 V / 3 A, SM110G, SM126G, SM130G, SM145G : DC 50 V / 5 A 9 Definition of Terms Rated Functioning Temperature Rated functioning temperature is the operating temperature of thermal cutoffs, measured using the method specified in the safety standard. In present E.A.M.C. (Electrical Appliance and Material Control) Law of Japan, Valid until June 2001, the operation should be within the specified operating temperature range of 7C. In various standards such as UL, CSA, VDE, BEAB and new E.A.M.C. Low of Japan, which comply with the IEC standard, it is called the rated functioning temperature, and should operate within the prescribed temperature range of +0/-10 C. It is represented by the symbol TF in the UL standard, and by the symbol Tf in the CSA, VDE and BEAB and new E.A.M.C. standards. In SEFUSE, a temperature that complies with both standards is set as the rated functioning temperature, and is indicated on the body of the thermal cutoff. Operating Temperature Operating temperature is the actual operating temperature range when the thermal cutoff is made to operate inside a constant temperature oven whose temperature is raised at the rate of 1 C/min. while a detection current of 100 mA or lower is applied. The operating temperature is a standard set by NEC and is not specified by a safety standard. TH, Th, Tc (Holding Temperature) Holding temperature is the maximum temperature at which, when applying a rated current to the thermal cutoff, the state of conductivity is not changed during specified time not hess than 168 hours (1 week). It is represented by the symbol TH in the UL standard, Th in the CSA standard, and Tc in the VDE, BEAB and new E.A.M.C. standards. TM, Tm (Maximum Temperature Limit) Maximum temperature limit is the temperature up to which thermal cutoffs will not change its state of cutoff without impairing. It is represented by the symbol TM in the UL standard and by Tm in the CSA, VDE, BEAB and new E.A.M.C. standards. Rated Current Reted current is the maximum current that thermal cutoffs allow to carry and are able to cutoff the circuit in safety. Rated Voltage Reted voltage is the maximum voltage that is allowed to apply to the circuit in wich the thermal cutoff is used. 10 SEFUSE TM Performance Data SF/E & SF/Y Series Temperature Rise Response Time (C) 40 30 Time for opening after immersion into oil (seconds) Temperature Rise (C) SF/E SF/Y 20 10 40 30 20 10 0 5 5 10 15 10 20 30 40 Temperature Difference (C) (oil temp. minus operating temp.) 20 Pass-through Current (A) Initial Characteristics SF169E & SF169Y SF139E & SF139Y SF109E & SF109Y SF96E & SF96Y SF70E & SF70Y Part Number High Temperature Storage Test 169 106 2.0 1.5 168 105 1.5 1.0 SF169E E 104 1.0 0.5 Y 140 106 2.0 1.5 E 105 138 104 1.0 0.5 Y 112 106 2.0 1.5 E 1.0 110 104 1.0 0.5 Y 97 106 2.0 1.5 E 96 105 1.5 1.0 1.0 0.5 Y 71 106 2.0 1.5 E 70 105 1.5 1.0 Operating Temperature (C) 1.0 (M) (kV) -2 @76C +2 & 0 -2 SF70E @50C +2 & 0 SF70Y Y -2 Internal Resistance (m/25 mm) Part Operating Number Temperature 0.5 Insulation Withstand Voltage Resistance after after Operation Operation 0 SF96Y 1.0 @89C +2 & SF96E 95 104 -2 SF109Y 104 69 0 SF109E 105 @119C +2 & SF139Y 111 1.5 0 -2 SF139E 139 1.5 & SF169Y 167 @140C +2 Change of (C) 0 10 100 1,000 10,000 Time (Hours) Note : The values following @ are the storage temperature. 11 SM/A Series Temperature Rise Response Time (C) 6 4 , , , , , , , , ,, ,,,, ,,,,,,,,,,,,,, ,,,,,,,, ,, 30 SM095A0 SM110A0 SM126A0 SM130A0 SM145A0 Time for opening after immersion into oil (seconds) Temperature Rise (C) 5 3 2 1 SM095A0 SM110A0 SM126A0 SM130A0 SM145A0 20 10 0 0 1 2 Initial Characteristics SM130A0 SM126A0 SM110A0 SM095A0 30 40 50 High Temperature Storage Test 106 3.0 3.4 145 105 2.0 3.0 144 104 1.0 2.6 -5 131 106 3.0 4.4 +5 130 105 2.0 4.0 129 104 1.0 3.6 -5 127 106 3.0 4.4 +5 126 105 2.0 4.0 125 104 1.0 3.6 -5 111 106 3.0 4.4 +5 110 105 2.0 4.0 109 104 1.0 3.6 -5 99 106 3.0 11 +5 98 105 2.0 9 97 104 1.0 7 Withstand Voltage Operating Internal Resistance after after Operation Temperature Resistance Operation (kV) (C) (m/25 mm) (M) @125C +5 146 SM145A0 SM130A0 SM126A0 SM110A0 SM095A0 0 @110C 0 @106C 0 @90C 0 @75C 0 -5 Insulation Part Number 20 Temperature Difference (C) (oil temp. minus operating temp.) Pass-through Current (A) SM145A0 10 Part Number Change of Operating Temperature (C) 0 10 100 1,000 10,000 Time (Hours) Note : The values following @ are the storage temperature. 12 SEFUSE TM SM/B Series Temperature Rise Response Time 10 9 SM095B0 SM110B0,SM126B0,SM130B0 SM145B0 , , , ,,,,,,,, , , , , , , ,,,,,,,,,,,, , , ,, 30 Time for opening after immersion into oil (seconds) Temperature Rise (C) 8 7 6 5 4 3 2 1 20 10 0 0 1 2 3 SM095B0 SM110B0 SM125B0 SM130B0 SM145B0 10 20 30 40 50 Temperature Difference (C) (oil temp. minus operating temp.) Pass-through Current (A) Initial Characteristics SM145B0 SM130B0 SM126B0 SM110B0 SM095B0 High Temperature Storage Test 146 106 3.0 4.0 145 105 2.0 3.5 144 104 1.0 3.0 -5 130 106 3.0 4.7 +5 129 105 2.0 4.6 128 104 1.0 4.5 -5 127 106 3.0 4.8 +5 126 105 2.0 4.6 125 104 1.0 4.4 -5 112 106 3.0 4.7 +5 111 105 2.0 4.6 110 104 1.0 4.5 98 106 3.0 9.5 +5 97 105 2.0 9.0 0 96 104 1.0 8.0 SM145B0 SM130B0 SM126B0 SM110B0 Withstand Voltage Operating Internal Resistance after after Operation Temperature Resistance Operation (kV) (C) (m/25 mm) (M) 0 @110C 0 @106C 0 @90C 0 -5 SM095B0 @75C -5 Insulation Part Number @125C +5 Part Number Change of Operating Temperature (C) 0 10 100 1,000 10,000 Time (Hours) Note : The values following @ are the storage temperature. 13 SM/G Series Temperature Rise , , , , , ,,,,,,,,,, ,,,,,,,,,,,, ,,,,,,,,,,,,,,,,,, , , ,, , SM095G0 Time for opening after immersion into oil (seconds) Temperature Rise (C) 10 Response Time SM110G0 SM125G0 SM130G0 SM145G0 5 30 SM095G0 SM110G0 SM126G0 SM130G0 SM145G0 20 10 0 0 1 2 3 Initial Characteristics SM130G0 SM126G0 SM110G0 SM095G0 106 3.0 5.0 145 105 2.0 4.0 144 104 1.0 3.0 -5 131 106 3.0 6.0 +5 130 105 2.0 5.0 129 104 1.0 4.0 -5 127 106 3.0 6.0 +5 126 105 2.0 5.0 125 104 1.0 4.0 -5 112 106 3.0 6.0 +5 111 105 2.0 5.0 110 104 1.0 4.0 -5 99 106 3.0 13.0 +5 98 105 2.0 11.0 97 104 +5 SM145G0 SM130G0 SM126G0 SM110G0 SM095G0 9.0 Withstand Voltage Operating Internal Resistance after after Operation Temperature Resistance Operation (kV) (C) (m/25 mm) (M) @125C 0 @110C 0 @106C 0 @90C 0 @75C 0 -5 Insulation Part Number 30 High Temperature Storage Test 146 1.0 20 Temperature Difference (C) (oil temp. minus operating temp.) Pass-through Current (A) SM145G0 10 Part Number Change of Operating Temperature (C) 0 10 100 1,000 10,000 Time (Hours) Note : The values following @ are the storage temperature. 14 SEFUSE TM Lead Cutting and Taping NEC will perform lead cutting or taping as requested by customers. K Applicable Products SF type : SF E (only for lead cutting), SF E-1 Does not apply to the SF/Y series. K SM A0, SM B0, SM G0 (short lead type) SM type : Taping reel 285 Z 75 P 30 R R t 89 L1 S L2 T W SF type: 2000 pcs/reel SM type: 2500 pcs/reel S T (75) (Unit : mm) W P L1 - L2 522 632 50.5 2.0 672 K T Z R t S 61 2.0 0.5 3.2 0.8 Lead Cutting SF Type L1 : 7 to 30 L2 : 7 to 33 (mm) L1 L2 SM Type L1, L2 : 7 to 33 (mm) L1 L2 For more information on dimensions not described in diagrams above, please call NEC. 15 Cautions This section describes cautions designed to protect the performance of the thermal cutoff. Be sure to read and fully understand these cautions. To obtain full performance from the thermal cutoff, it is necessary for the customer to appropriately store the thermal cutoff, design appropriate circuits for the application, and perform evaluations, mounting and testing as necessary. Problems arising from the inappropriate execution of the above are the responsibility of the customer, and NEC declines any and all responsibility. Design Cautions Do not use this device for and purpose other than as a thermal cutoff. The thermal cutoff is designed to detect abnormal rises in temperature and break circuits if needed. It is not a current fuse that cuts excess current. If used as a current fuse, the SEFUSE may malfunction. Do not use this device in aerospace equipment, aeronautical equipment, nuclear reactor control systems, Iife support equipment or systems, transportation machinery engine control or safetyrelated equipment. This device is designed for use in household electric appliance, office automation equipment, audio and video equipment, computer communications equipment, test and measurement equipment, personal electronic equipment and transportation equipment (excluding engine control). The customer should select the proper thermal cutoff device, mounting location, and mounting method as appropriate for each application. Verify whether the chosen selections are appropriate by repeatedly testing the final design for thermal cutoff under normal conditions as well as under predicted maximum abnormal conditions. Make designs so that the temperature of the body of the thermal cutoff does not exceed the temperatures shown in Table 1. If, the temperature is exceeded on a regular basis, the thermal cutoff may start operating only at temperature lower than the normal operating temperature. Malfunctions may also occur. Even if the thermal cutoff's operating temperature is exceeded, it may malfunction. 16 SEFUSE SM Type TM SF Type Type Body Temperature Type Body Temperature SM065A SM095A, B, G SM110A, B, G SM126A. B. G SM130A, B, G SM145A, B, G SM164A SM182A 45 C 75 C 90 C 106 C 110 C 125 C 140 C 140 C SF 70E, Y SF 76E, Y SF 91E, Y SF 96E, Y SF109E, Y SF119E, Y SF129E, Y SF139E, Y SF152E, Y SF169E, Y SF188E, Y SF214E, Y SF226E, Y SF240E, Y 50 C 56 C 71 C 76 C 89 C 99 C 109 C 119 C 132 C 140 C 140 C 140 C 140 C 140 C Table 1 The body temperature of the thermal cutoff becomes higher as current passes through and might rise higher than the ambient operating temperature (see test data). The temperature may rise even higher depending on the mounting method and other conditions. Therefore, after mounting the thermal cutoff under the same conditions you would use for the actual application, work the final product and measure the body temperature of the thermal cutoff. Use the thermal cutoff with a voltage and current level lower than the rated level. If the thermal cutoff is used with a voltage or current level higher than the rated level, contacts may melt in the SF type, causing the fuse to malfunction. In the SM type, the body of the thermal cutoff may be destroyed. Do not use the thermal cutoff in water, organic solvents or other liquids, or environments containing sulfurous acid gas, nitrous acid gas, or high humidity. Doing so will cause deterioration of the sealing resin, the thermal cutoff may operate at lower than operating temperature, or any other malfunctions may occur. Also, the thermal cutoff may not operate even if its operating temperature is exceeded. 17 Lead wire process When bending the lead wire, in order to protect the resin seal from excessive pressure, secure the lead wire cIose to the case and bend the part beyond the secured section. 3 mmor more ,,,,, ,, ,,,,, ,, ,,,,, , ,,,,, , Secured Secured The lead wire should be bent at a distance 3 mm or more from the body of the fuse, and should not be twisted. The tensile strength applied to the lead wire should be 5 kg or less for the SF type, and 1 kg or less for the SM type. The strength applied to the body of the thermal cutoff should be 10 kg or less for the SF type, and 5 kg or less for the SM type. SF(10 kgf) SM(5 kgf) 0.8 steel wire In the case of an SF type, deformation of the case may change the location of the moving electrode during operation and may cause the thermal cutoff to operate only at temperatures lower than the normal operating temperature range. The thermal cutoff also may not operate even if the thermal cutoff's operating temperature is exceeded. Mounting SEFUSE can be mounted by soldering, caulking, or welding. If soldering, note that the thermal cutoff may not function because of excessive solder temperature. To prevent such malfunctions, for example, holding the lead new the case by a tool is effective for allowing the heat to escape, and the soldering should be done in short interval. Another effective method is to use a lower solder temperature and to solder at a location that is distant from the case. If caulking or welding, be careful to keep the resistance value of the connecting section low. If the connecting section has a high resistance value, the passing current may generate an abnormally high temperature that will cause the thermal cutoff to operate (break the circuit). 18 TM SEFUSE It is recommended that the connecting position at the lead of resign-sealed side should be 5 mm or more from the body of the thermal cutoff. 5 mm or more Connecting Position 5 mm or more 5 mm or more Connecting Position After mounting the thermal cutoff, be careful not to apply force that may pull, push or twist the lead wires. If using an SF type thermal cutoff, be sure not to make the lead on the resin-sealed side touch the case. This would cause the current to flow from the lead on the resin-sealed side to the opposite lead so that the thermal cutoff cannot break the circuit. Note that the body of the SF type is the same in potential as the circuit. Therefore, it must be electrically isolated from the other metalic part. Storage The body and lead A of SF type, and the leads of SM164A and SM182A are silver-plated. Therefore, these parts may discolor because of sulfuration. In the case, the marking of the body wiII become difficult to discriminate or the solder-abiIity of lead wiII decline. To avoid this, the SEFUSE should not keep around materials (such as cardboard or rubber, etc.) which generate sulfurous acid gas. When the SEFUSE have to be storaged in a cardboard box, the SEFUSE's packs should be put into other bags (such as polyethylene) and make sure the packs seal. Recommendation Be careful when mounting the thermal cutoff because external force, heat, or a harmful atmosphere (containing excessive humidity or sulfurous acid gas) may damage the characteristics of the thermal cutoff. If applicable, it is recommended to warn general consumers who are not aware of the usage cautions for the thermal cutoff not to mount, remove or replace the thermal cutoff through a note to this effect in the user's manual and other related material. If you desire any clarifications or explanations regarding these cautions, please call an NEC sales representative. The values contained in this document were obtained under certain testing conditions at NEC. They are not guaranteed and are for reference only. 19 The information in this document is based on documents issued in February, 1999 at the latest. The information is subject to change without notice. For actual design-in, refer to the latest publications of data sheet, etc., for the most up-date specifications of the device. No part of this document may be copied or reproduced in any form or by any means without the prior written consent of NEC Corporation. NEC Corporation assumes no responsibility for any errors which may appear in this document. NEC Corporation does not assume any liability for infringement of patents, copyrights or other intellectual property rights of third parties by or arising from use of a device described herein or any other liability arising from use of such device. No license, either express, implied or otherwise, is granted under any patents, copyrights or other intellectual property rights of NEC Corporation or others. While NEC Corporation has been making continuous effort to enhance the reliability of its electronic components, the possibility of defects cannot be eliminated entirely. To minimize risks of damage or injury to persons or property arising from a defect in an NEC electronic component, customer must incorporate sufficient safety measures in its design, such as redundancy, fire-containment, and antifailure features. NEC devices are classified into the following three quality grades: "Standard", "Special", and "Specific". The Specific quality grade applies only to devices developed based on a customer designated "Quality assurance program" for a specific application. The recommended applications of a device depend on its quality grade, as indicated below. Customers must check the quality grade of each device before using it in a particular application. Standard: Computers, office equipment, communications equipment, test and measurement equipment, audio and visual equipment, home electronic appliances, machine tools, personal electronic equipment and industrial robots Special: Transportation equipment (automobiles, trains, ships, etc.), traffic control systems, anti-disaster systems, anti-crime systems, safety equipment and medical equipment (not specifically designed for life support) Specific: Aircrafts, aerospace equipment, submersible repeaters, nuclear reactor control systems, life support systems or medical equipment for life support, etc. The quality grade of NEC devices is "Standard" unless otherwise specified in NEC's Data Sheets or Data Books. If customers intend to use NEC devices for applications other than those specified for Standard quality grade, they should contact an NEC sales representative in advance. Anti-radioactive design is not implemented in this product. 20 SEFUSE TM Application Examples Electric Iron Transformer LCD Television Rice Cooker Remark() For the purpose of photography, the insulation tube of the thermal cutoff has been removed. In reality, the thermal cutoff is covered by the insulation tube. Inverter for EL Light Drive 19 21 For further information, please contact: NEC Corporation NEC Building 7-1, Shiba 5-chome, Minato-ku Tokyo 108-8001, Japan Tel: 03-3798-6148 Fax: 03-3798-6149 [North & South America] NEC Electronics Inc. Electron Components 2880 Scott Boulevard, M/S SC900 P.O.Box 58062 Santa Clara, CA 95052-2554, U.S.A. Tel: 408-588-6160 Fax: 408-588-6130 (Regional Sales Offices) Central Region Greenspoint Tower 2800 West Higgins Road Suite 765 Hoffman Estates, IL 60195, U.S.A. Tel: 708-519-3930 Fax: 708-519-9329 Northern California Region 3033 Scott Blvd. Santa Clara, CA 95054, U.S.A. Tel: 408-588-5100 Fax: 408-588-5134 Eastern Region 901 N. Lake Destiny Drive Suite 320 Maitland, FL 32751, U.S.A. Tel: 407-875-1145 Fax: 407-875-0962 Western Region One Embassy Centre 9020 S.W. Washington Square Road Suite 400 Tigard OR 97223, U.S.A. Tel: 503-671-0177 Fax: 503-643-5911 Document No. Date Published (c) [Asia & Oceania] NEC Electronics Hong Kong Ltd. 12/F, Cityplaza 4, 12 Taikoo Wan Road, Hong Kong 2886-9318 Tel: Fax: 2886-9022, 2886-9044 Seoul Branch 10F, ILSONG Bldg., 157-37, Samsung-Dong, Kangnam-Ku, Seoul, The Republic of Korea Tel: 02-528-0303 Fax: 02-528-4411 Shen-zhen Office 31st, Floor, Shen-zhen International Financial Bldg. 23 Jian She Road, Shenzhen, China Tel: 755-2227094 Fax: 755-2256360 Australia Representative Office 303-313 Burwoood Highway Burwood East, Victoria 3151,Australia Tel: 03-98878012/98878013 Fax: 03-98878014 NEC Electronics Taiwan Ltd. 7F, No. 363 Fu Shing North Road Taipei, Taiwan, R.O.C. Tel: 02-2719-2377 Fax: 02-2719-5951/5936 NEC Electronics Singapore Pte., Ltd. 101 Thomson Road #04-02/05 United Square Singapore 307591 Tel: 65-253-8311 Fax: 65-250-3583 EM0060EJ8V1SG00 (8th edition) February 1999 M 1989 (1997) Printed in Japan