ina) Hot-Molded Panel Potentiometers Features Benefits # 1,000,000 Mechanical Cycles ......... Long Rotational Life Slip Clutch ............. cece ee eee ee Durability . @ 2.25 Watts @ 70C .............008. High Power Capabilities #50 Ohms to 5 Megohms ............. @ Wide Resistance Range @ Linear and Non-Linear Tapers ........ @ Versatility SPECIFICATIONS General Availability Type EJ Hot-Molded Panel Potentio- meters are custom products. Refer to Type J Potentiometer information on Pages 194 and 196 for definitions of standard and custom components. Temperature range 55 C to +120 C. Total resistance tolerances + 20% or + 10%. Tapers Available in the following resistance ranges: Electrical TAPER TOTAL RESISTANCE RANGE U 50 Ohms to 5.0 Megohms A, B, S, & DB 250 Ohms to 5.0 Meagohms See Chart on Page 204 for explanation of tapers. Special tapers, where practical, can be supplied. End Resistance See chart on Page 204. Power 2.25 watt maximum at +70 C (single resistors only) provided voltage rating is not exceeded. Power derating Derate power linearly from + 70 C to zero at + 120 C. Derate power 50 percent for non-metallic mounting and for resistors with A, B, S, and DB tapers. See following pages for additional power derating information. Voltage 500 volts maximum working voltage (RMS or DC), or as determined by Emax =PR, whichever is less (at sea level). Dielectric withstanding voltage Maximum continuous voltage 500 volts (RMS or DC) at sea level. Will withstand a one second test of 1000 volts (RMS or DC) at sea level or 500 volts (RMS or DC) at 3.4 inches (86,36 mm) mercury. Voltage characteristic 0.005 percent per volt or 0.5 ohm, whichever is greater. Capacitance The capacitance between terminal #1 and #3 with terminal #2 floating is approxi- mately 2 to 3 pF at 1 KHz. 202Type EJ Electrical (continued) The capacitance between terminal #1 (grounded to bushing) and terminal #3 (shaft in extreme clockwise position) is approximately 10 to 12 pF at 1 KHz. The capacitance between all terminals shorted together and the bushing is approximately 15 to 20 pF at 1 KHz. Operational In all cases capacitance indicated is for potentiometer only and does not include capacitance of connecting wires. Load life 10 percent maximum change in total resistance as a result of a 1000 hour test at rated power across entire element in still air at + 70 C (1.5 hours ON, 0.5 hour OFF). Mechanical Rotational life 10 percent maximum change in total resistance as a result of a 1,000,000 mechanical cycle life test without load. Slip clutch The single section Type EJ is available with a slip clutch as Type EJC that prevents damage to the variable resistor when the shaft is rotated past the end stops. Slip torque is 2+1 inch-pounds (2,31+1,15 kaf-cm). Shafts Diameter of shafts .250 inch (6,35 mm). Minimum length .125 inches (3,17 mm) longer than bushing. Maximum length 6.000 inches (152,40 mm). Lengths available in 1/64 inch (0,40 mm) increments. All shaft lengths are measured from the mounting face of the resistor to the free end of the shaft. Bushings Plain bushings only. All bushings have a 32-NEF-2A thread and are .375 inch (9,52 mm) in diameter. Length .250 inch (6,35 mm), .375 inch (9,52 mm) or .500 inch (12,70 mm), measured from the mounting surface of the bushing. Hardware Resistors are normally supplied with one mounting nut M-2786 and one internal tooth lock washer M-2898. Unless otherwise specified, all hardware shipped in bulk. Locating lugs Two locating lugs are applicable so resistors may be indexed with respect to the surface on Environmental which they are mounted. Four lug options available. Lug option 1 standard. See dimensions on following pages. Turning torque At + 25 C minimum torque 1 inch-ounce (0,07 kgf-cm). Maximum torque as follows: Single 6 inch-ounces (0,43 kgf-cm) Dual 9 inch-ounces (0,65 kaf-cm) Stop torque 12 inch-pounds (13,82 kaf-cm) minimum. Rotation Mechanical 312 + 3. Electrical 292 nominal. Backlash Maximum backlash: single resistors + 1-1/2, dual resistors + 3. Construction Materials are corrosion resistant and essentially non-magnetic; enclosure is dust and splash resistant; terminals are treated for easy soldering. Marking Clarostat part number and nominal total resistance are marked in two lines. Other marking possible, limited to maximum of 13 characters in each of two lines. Type EJ always included. Vibration 2 percent maximum change in total resistance, 5 percent maximum change in resistance setting. (Tested per method 204, condition C of MIL-STD-202.) Shock 2 percent maximum change in total resistance. 5 percent maximum change in resistance setting. (Tested per method 213, condition I of MIL-STD-202.) Moisture resistance 10 percent maximum change in total resistance. (Method 106 of MIL-STD- 202.) Corrosion resistance Materials show no corrosion after a 200 hour salt spray test. (Method 101 of MIL-STD-202.) Effect of soldering 2 percent maximum change in total resistance as a result of immersing the terminals in + 350 C solder to within 0.125 inch (3,18 mm) of the resistor body for 5 seconds. Temperature cycling 3 percent maximum change in total resistance as a result of the 203 temperature cycling test (five cycles 55 C to + 120 C). Low temperature operation 3 percent maximum change in total resistance as a result of the low temperature operation test ( 55 C for two hours without load and 45 minutes with rated load). Low temperature storage 2 percent maximum change in total resistance as a result of the storage test (24 hours at 55 C), Temperature characteristics Maximum percent temporary total resistance change from the + 25 C value. See table below. Nominal Degrees Celsius U Linear Taper Resistance |55|25| 0 |+25)+55|+85| +120 100 Ohms |*+ 4.5/+25/+15} 0 J+1.0)+15/+35 1,000 Ohms |+ 5.5/+3.0]/+15] 0 J+10/+20/+ 4.5 10,000 Ohms |+ 7.0/+3.5)/+2.0| 0 |#+1.0/+2.5/+5.5 100,000 Ohms |+ 8.0/+4.0}+2.0} 0 [+15]/+3.0/+ 6.0 1 Megohm +10.0/+5.0)/+25) 0 1+1.5/+435/+75 For S, A, B and DB tapers multiply percent- age figures shown above by 1.25.Type EJ Taper Data 100K TAPERS END RESISTANCE eerie MINIMUM | MINIMUM 90K aracteristics or for Total Resistance EE LEENS ta Ni 80K f 100K , TERMINALS | TERMINALS TAPER land2 2 and3 _o U&S o oO g A oO 3 B uo 2 oe DB Bo B 20K 10K 0 40 50 60 70 80 9% Percent Clockwise Mechanical Rotation 100 Tapers A, DB, S and U are measured between the wiper and the counter-clockwise terminals: taper B is measured between the wiper and the clockwise terminals. Additional Ratings @ Less than .004% of total resistance, or less than 4 ohms, whichever is less. Less than 1% of total resistance, or less than 4 ohms, whichever is less. Less than 4 ohms. Multiple resistor power derating The permis- sible power dissipation in one resistor element is a function of the power dissipation in the other resistor element. Maximum continuous power rating in watts with entire resistor element in the circuit are as follows: W1\2 ~/We 2.25 18 Where W = Watts in entire first or panel resistor element. y = 1 (Maximum) Wa = Watts in entire second or rear resistor element. WATTS Wy | 2.25] 2.00} 1.75| 1.50] 1.25 | 1.00 |0.75 |0.50 |0.25 | 0 Wo] 0 {0.83} 1.13] 1.34] 1.49 | 1.61 | 1.70 | 1.76 | 1.79 [1.80 Derating with respect to rotation rheostat application Multiply Multiply Percent Wattage Percent Wattage Rotation | Rating By | Rotation | Rating By 100 1.00 40 0.81 90 0.99 30 0.68 80 0.98 20 0.49 70 0.96 10 0.23 60 0.93 0 0.11 50 0.89 204Explanation of Part Numbers Type EJ Basic Type EJA Single EJ EJD Dual EJ* EJC Single EJ with Slip Clutch * If the electrical specifications are not identical for each section, a special part number will be required. Locating Lug Option BwhN Total Resistance Value First two digits are significant | figures and the third indicates the number of zeros following the first two digits Examples: 101 = 100 Ohms 501 = 500 Ohms 255 = 2.5 Meqohms | = EJA2N056S501U : Tt | Bushing Type and Length G Plain .250 inch (6,35 mm) long N Plain .375 inch (9,52 mm) long H Plain .500 inch (12,70 mm) long Measured from mounting surface in inches and sixty-fourths Preferred Shaft Length and Endings Shaft Length Shaft Ending S Screwdriver Slotted P Plain Round F Standard Flat Example: 032 = 32/64 or .500 inch (12,70 mm) 056 = 7/8 or .875 inch (22,22 mm) 200 = 2.000 inches (50,80 mm) Type EJ and Type EJD Taper Type and Total Resistance Tolerance U Linear (U), + 10% M Linear (U), = 20% A Clockwise Modified Logarithmic (A), + 10% R Clockwise Modified Logarithmic (A),+ 20% B Counterclockwise Modified Logarithmic (B), + 10% T Counterclockwise Modified Logarithmic (B), = 20% D Clockwise Exact Logarithmic (DB), + 10% Plain Round {Screwdriver Slotted K Clockwise Exact 500 (12,70 mm) | 500 (12,70 mm) Is pogarithmic ote 208 .625 (15,88 mm) | 625 (15,88 mm) Y Mo. life Linear ey + 750 (19,05 mm) | .750 (19,05 mm) Modified Linear (S), + 20% .875 (22,22 mm) .875 (22,22 mm) 2.000 (50,80 mm) = CAUTION: Not all possible part number combinations Type EJC are valid. Check parameter limits in text. .875 (22,22 mm) .875 (22,22 mm) _ 2.000 (50,80 mm) EXAMPLE = EJA1N024P501U Invalid Bushing/Shaft Combination Plain .375 inch (9,52 mm) long bushing with .375 inch (9,52 mm) long shaft. Ordering Information Type (EJA, EJD, EJC). 7. Shaft length from mounting surface in inches. Taper (each element on multi-section controls). 8. Locating lug option (1,2,3 or 4). Total resistance value (each element on multisection 9. Mounting hardware (A-B Standard or Other). controls) in ohms. 10. Part number you have assigned, if any. Bushing type. 11. Marking required on the part. Bushing length in inches. 12. Special features. * Do wher Shaft ending (plain, slotted, or flatted). *Forward complete detailed specifications to the factory. 205DIMENSIONS Type EJ Single Resistor Type EJA or Type EJC 1.156 _ Dia. (29,36) Max. Bushing Lengths 250 375 500 Surface Shaft Endings Dual Resistor 5314 .005 (13,49 + 0,13) 018 + .005 (0,46 # 0,73) Type EJD 875 + .031 (22,22 + 0,80) Ne / | p 3 oo 2 32 NEF ~ 2A Thread 6.35) ~ an) Lengths from .375 (9,52) minimum (6.99) (9.92) (12,70) Mounting] to 6-000 (152.40) maximum Screwdriver Slot Shaft in extreme counterclockwise position Slot ons 005 Wide (1,19 0,13) Screwdriver slot in line with movable contact All shafts supplied with maximum Flatted Flat will extend to within .031 (0,80) of mounting bushing where shaft length will not permit standard flat. rN 625 (15,8871 fr ta? ! _t -216 + .002 (5,49 2 0,05) Shaft in extreme counterclockwise position Flat opposite movable contact chamfer .031 (0,80) x 45 at the shaft end. Locating Lug Options Mounting Holes 531+ .005 (13,49 + 0,13) (< 531+ .005 (13,49 2 0,13) .\ 531+ .005 (13,494 0,13) 1 d mY ry XY Lv Lf Option No. 1 Option No. 2 Option No. 3 Standard Locating Lug (Used Untess Otherwise Specified) Option No. 4 No Locating Lugs 531+ .005 (13,494 0 13) .406 Dia. Minimum naa Minimum (10,32) . (If Required) .128 Dia. Minimum (3,25) ny bo Resistor Connections | Mounting Hardware - 030 (0,76) (12,70) ] 12,70) 030 (0, , 098 1220) cc (2,38) When Mounted (O) Lock Washer M-2898 Mounting Nut M-2786 TOLERANCES Dimensional Tolerance + .016 (0,40) Angular Tolerance + 5 Except as specified. NOT TO SCALE Basic dimensions in inches. Dimensions shown in PARENTHESES are in millimeters. . 206