1、CQ I ,. I fn a: cc iiJ ANSI C83.48-1974 Approved November 15, 1974 AMERICAN NATIONAL STANDARDS INSTITUTE EIA STANDARD Fixed Composition Resistors RS172-B (Revision of RS172A) MARCH 1975 Engineering Deportment ELECTRONIC INDUSTRIES ASSOCIATION NOTICE EIA engineering standards are designed to serve th
2、e J?.Ublic interest through eliminting mis understandings between manufacturers and purchasers, facllitating interchangeability and improve ment of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existence. of such stand
3、ards shall not in any respect pre clude any member or non-member of EIA from manu“facturing or selling products not conforming to such standards, nor shall the existence of such standards preclude their voluntary use by those otber than EIA members whether the standard is to be used either domestica
4、lly or internationally. ecommended standards are adopted by EIA without regard to whether or not their adoption may involve patents on articles, materials, or processes. By such action, EIA does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopt
5、ing the recommended standards. Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineering Department 2001 Eye Street, N.W., Washington, D. C. 20006 0 Electronic Industries Association 1975 All rights reserved Printed In U.S.A. FIXED COMPOSITION RESISTORS (From EIA Standard RS-172 and Standards Propo
6、sal No. 1164, formulated under the cognizance of EIA Working Group P-1.1 on Fixed Components) 1. SCOPE 1,1 This standard covers insulated, fixed resistors having a composition resistance element and !lapable of full load operation at an ambient temperature of 70C. This standar describes minimuUl lim
7、its of performance commonly -ubserved in commercially available produody of the resistor does not extend beyond the extremeties of the block. The resistor leads shall he so positioned that the distance between the resistor leads and the V-hlock shall be not less than the radius of the resistor minus
8、 the radius of the lead wire. 3.2.5.2 Procedure- The rms voltage at commercial line frequency not exceeding 100Hz specified in Table VII shall be applied to the resistors for 5 seconds between the resistor terminals connected together and the V -block at atmospheric pressure. TABLE VII DIELECTRIC WI
9、THSTANDING VOLTAGE Resistor Wattage RMS Volts 1/8 300 1/4 500 1/2 700 1 1000 2 1000 RS-172-B Page10 3.2.6 Short Time Overload (see 2.8)- Following a measurement of resistance, a potential of 2.S :X the rated continuous working voltage (see 2.3) shall be applied for S seconds. In no case shall the vo
10、ltage exceed the applicable value listed in Table VIIi. Resistance shall be measured 30 minutes after removal of the test potential. -CAUTION: Test potential shall he established by use of a dummy load to avoid excess stress on the test specimens. TABLE VUI MAXIMUM OVERLOAD VOLTAGE Power Rating Maxi
11、mum Voltage Watts (de or peak ac) Volts 1/8 200 1/4 400 1/2 700 1 1000 2 1000 3:2.7 Low Temperature Operation (see 2.9)- Following the resistance measurement, resistors shall be placed in a cold chamber maintained at a temperature of -65C + 0C -SC; After 1 hour of stabilization at this temperature,
12、full rated working voltage, as specified in 2.3, shall he applied for 4S minutes. Resistors may-he loaded individually or in parallel. 1S +S -0 minutes after the removal of voltage, the specimens shall be removed from the chamber and maintained at a temperature of 2SC SC for a period of 24 hours, af
13、ter which resistance measurements shall again he made. 3. 2. 8 Temperature Cycling (see 2.1 0) 3.2.8.1 Mounting- Resistors shall he_ mounted by their terminals so that there shall be at least 1“ of free airspace around each resistor, and with the mounting in such a position with respect to the air s
14、tream that it offers substantially no obstruction to the flow of air across and around the resistors. 3.2.8.2 Procedure- Resistors shall be subjected to the temperature cycle shown in RS-172-B Page 11 Table IX for a total of 5 cycles performed continuously. The air temperature shall he mered by a su
15、itable means and as near the center of the group of resistors as possible. If a thermometer is used, it shall be mounted parallel to the axis of the resistor. The temperature shall be maintained at each of the extreme temperatures by means of circulat ing air. The hot and cold chamber shall be of su
16、ch capacity that the air at the resistors will reach the temperature specified in Table IX within 2 minutes after the resistors have been transferred to the appropriate chamber. Resistors shall not he subjected to circulat ing air for the 10 to 15 minute periods at room temperature (25 5C). Measurem
17、ents of resistance shall he made before the first cycle and within 24 hours after the fifth cycle. . TABLE IX TEMPERATURE CYCLE Sequenc Temperature Time oc Minutes Start at +25 S 10 to IS Reduce to -55 +0. -3 30 Return to +25 5 10 to IS Raise to +85, +3, -0 30 Return to +25 5 10 to 15 3.2.9 Humidity
18、 (see 2.11),- Following measurement of resistance in a dry atmosphere of 25C .5C, resistors shall he placed in an atmosphere of 40C 2C and 90% to 100% . relative humidity for 240 8 hours. Resistors shall he removed at the end of this period, air dried for 1 hour 15 minutes, and final resistance meas
19、ured. 3.2.10 Load Life (see 2.12) 3.2.10.1 Test Conditions- This test shall he conducted at an ambient temperature of 70C 5C. Resistors shall be mounted and soldered or clipped to terminals. The effective length of each lead shall be 1 “ 3/16 ! Resistors shall he so arranged that the temperature of
20、any one resistor will not appreciably influence the temperature of any other resistor. There shall he no circulation of air directly over the resistors other than that caused by the heat of the resistors. The voltage used shall he the rated continuous working voltage specified in 2.3. Adequate preca
21、utions shall be taken to maintain con stant voltage on resistors under test. RS-172-B Pagcd.2 3.2.11 Terminal Strength (see 2.13) 3.2.11.1 Measurements- Resistance shan be meill!ured-before the testing specified in 3.2.11.2 and after the testing specified in 3.2.11.3. 3.2.11.2 Direct Load- Resistors
22、 shall be held by one terminal and the load shall be gradually applied in the direction of the longitudinal axis of the re:istor until the applied load reaches 5 pounds for all styles except RRC05. Applied load shall be 2 pounds for style RRCOS. The applied load shall be maintained for S seconds. 3.
23、2.11.3 Twisting- Each wire lead shall be bent and twisted as specified in Figure 3. 3.2.12 Resistance o Soldering Heat (see 2.14)- Following a measurement of resistance, resistor . terminals shall be immersed, one at a time, for 3 . .1/2 seconds each in a pot of molten solder at a temperature of 3S0
24、C SC (2S0C SC for-style RRCOS) to a point 1/8 to 3/16 “ from the resistor body. Resistance measurements shall be made 24 4 hours after immersion. 4. PRECAUTIONARf NOTES 4.1 EXCESSIVE VOLTAGES- Application of the nominal rated continuous working voltage to a resistor having less than the nominal resi
25、stance because of a wide resistance tolerance will result in application of more than rated power with .probable shortening of resistor life. 4.2 PEAK VOLTAGE- When nonsinusoidal peak voltages in excess of 1.4 times the rated sine wave continuous rms voltage are applied to the resistors, care should
26、 be taken to determine the suitability of resistors for use in such applications. 4.3 SOLDERING- Care should be taken in soldering resistors, since all properties of a composition resistor may be seriously affected when soidering irons are applied too close to a resistor body or for too long a perio
27、d. The length of lead left between resistor body and soldering point should be not less than inch, nor should the required soldering time exceed 3 seconds. 4.4 HIGH ALTITUDE - All tests in this specification shall be performed at ambient atmospheric pressure. This fact should be considered when the
28、use of these resistors for high-altitUde conditions is contemplated. 4.S STORAGE- Resistors may change in resistance value when stored for extended periods in uncontrolled temperature and humidity conditions. FIGURE 3 TWISTING TEST PROCEDURE RESISTOR G-t-t-1/32 R (.76) METAL PLATE A CHUCK ON SHAFT W
29、HICH CAN BE ROTATED THROUGH 360 .- -t-._“1 - - -RESISTOR UNDER TEST B 1. Bend lead with fingers over rounded adge of metal plate as shown in A. 2. Center resistor In chuck and secure lead in clamp as shown in B. .05 .02 (1.27.51) PADDED CLAMP HELD RIGID RS-172-B Page 13 3. The chuck shall be rotated
30、 a total of three 360 rotations In alternating directions. Rotations shall be continu ous through each 360 turn at a rate of two to five seconds per 360 rotation. During this test the chuck shall rotate around an axis which Is fixed with respect to the padded clamp. The chuck shall have no appreciab
31、le end play during rotation. 1.0 .125 .145 .015 1.0 .125 (25.4 3.18) (25.4 3.18) p I 3 G9 fO Of I .015.003 (0.38 0.08) TOLERANCE .062 .004 DIA (1.57 0.10) G E NUMBER OF ZEROS OR DECIMAL MULTIPLIER 2ND SIGNIFICANT FIGURE 1ST SIGNIFICANT FIGURE NOTE 1: All dimensions in inches, with metric equivalents
32、 in prentheses Minimum resistance 2. 7 ohms Maximum resistance 22 megohms Power Rating 1/8 watt Continuous working voltage (Maximum) 150 volts (See paragraph 2.3) SPECIFICATION SHEET Resistors, Fixed, Composition (Insulated), Style RRC05, 1/8 Watt :P !:; - = 1.5.125 I .250.031 I 1.5.125 (38.1 3.18l
33、I 16.350.79) I 138.1 3.18l ltie-;s, I ar ! .090 .008 DIA. (2.29 0.20) TOLERANCE I NUMBER OF ZEROS OR DECIMAL MULTIPLIER - 2ND SIGNIFICANT FIGURE - 1ST SIGNIFICANT FIGURE NOTE 1: All dimensions in inches, with metric equivalents in parentheses Minimum resistance 2.7 ohms Maximum resistance Power rati
34、ng Continuous working voltage (Maximum) (See paragraph 2.3) 22megohms 1/4 watt 250 volts SPECIFICATION SHEET Resistors, Fixed, Composition (Insulated), Style RRC07, 1/4 Watt “dUl II (JQ . n-J - c:.no:s +.041 1.5.125 1 .375-.031 I 1.5.125 2a1Bl ,+,.91 I c;asl I G ;=: : M .138.012DIA. (3.50 0.30) TOLE
35、RANCE NUMBER OF ZEROS OR DECIMAL MULTIPLIER 2ND SIGNIFICANT FIGURE 1ST SIGNIFICANT FIGURE NOTE 1: All dimensions in inches, with metric equivalents in parentheses Minimum resistance 2.7 ohms Maximum resistance Power rating Continuous working voltage (Maximum) (See paragraph 2.3) 22megohms 1/2watt 35
36、0volts SPECIFICATION SHEET Resistors, Fixed, Composition (Insulated), Style RRC20. 1/2 Watt := en :p.: QCl . (I c, 0 1.5.125 (38.1 3.18) : t .040 :-5-(1.02 0.13) 1.5 .125 (38.1 3.18) TOLERANCE r- n -, .225 0.15 DIA. (5.71 :!:0.38) G _Bq I NUMBER OF ZEROS OR DECIMAL MULTIPLIER L.- 2ND SIGNIFICANT FIG
37、URE “- 1ST SIGNIFICANT FIGURE NOTE 1: All dimensions in inches, with metric equivalents in parentheses Minimum resistance 2. 7 ohms Maximum resistance 22 megohms Power rating 1 watt Continuous working voltage (Maximum) 500 volts (See paragraph 2.3) SPECIFICATION SHEET Resistors, Fixed, Composition (
38、Insulated), Style RRC32, 1 Watt ;?f!l (JQ -l - -l!:O 1.5.125 I .688.040 I 1.5.125 (38.13.18) .,- (17.481.02) -(38.13.18) .045.!c: I WI ijm I (1.14 :1; 0.13) G .318.018DIA E (8.08 0.46) TOLERANCE I NUMBER OF ZEROS OR DECIMAL MULTIPLIER 2ND SIGNIFICANT FIGURE 1ST SIGNIFICANT FIGURE NOTE 1: All dimensi
39、ons in inches, with metric equivalents in parentheses Minimum resistance 10 ohms Maximum resistance 22 megohms Power Rating 2 watts Continuous working voltage (maximum) 500 volts (See paragraph 2.3) SPECIFICATION SHEET Resistors, Fixed, Composition (Insulated), Style RRC42, 2 Watts :tl ;p!fl ma- 01
40、. =0:1 RELATED EIA STANDARDS In addition to this Standard, the following EIA Standards are available on resistors: RS-155-B Fixed Wirwound Power Resistors . : . $3.60 RS-196-A Fixed Film Resistors (High Stability) . ; . . . . . . . $4.00 RS-229-A Fixed, Wirewounl, Precision Resistors . . . . . . . .
41、 . . . . . . . . . . . . . . . . . . . $3.30 RS-279 Color Code for Film Resistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $1.00 RS-296-C Reel Packaging of Axial Leaded Components $1.20 RS-303 Variable Control Resistors (Adjustable Composition Resistance Units) . . . . . .
42、 . . . . . . . . . . . . . . . . . . . . . . . . . . . $3.00 RS-333 Wirewound Variable Resistors I I e I I I I i I e I I I I I I I I I I I I I I I I I I I I $2.20 RS-344 Low Power, Insulated Fixed Wirewound Resistors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
43、 . . . . . . $3.30 RS-345 Resistors, Variable, Wirewound (Lead Screw Actuated) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $4.90 RS-360 Resistors, Variable (Lead-Screw Actuated) Non-Wirewound . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
44、. . . . . . . . . . $5.00 RS-391 Resistors, V ariahle, Wirewound, Precision . $10.00 RS-396 Resistots, Fixed Film 1licroelement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . $ 4.50 For a free and complete listing of EIA Standards and Engineering Publlcatiom write: EIA Engineering Department 2001 Eye Street, N.W. Washington, D.C. 20006
