Series 308 Potentiometer 1/2 in. sq. 0.5 Watt Description Series 309 Potentiometer The Series 308 and 309 are high-performance, low-cost 1/2 in. sq. 1.0 Watt potentiometers. They are also available with S.P.S.T. or S.P.D.T. rotary switch modules, S.P.S.T. momentary switch modules and/or potentiometer modules in multiple sections up to three sections. Features Compact - 1/2 in. (12.7mm) miniature, modular size. Cost-effective - Design simplicity through fewer component parts. Robust - Horizontal or vertical mountings with support plates. Nickel-plated brass shaft and bushings in various diameters and lengths. Insert molded gold plated terminals for strength. 308: Modular Style, Conductive Plastic Precision Made - screen-printed conductive plastic and thick-film cermet elements. 309: Modular Style, Thick-Film Cermet Stability - Series 308 -40C to +120C Series 309 -40C to 150C operating temperature. Series 308 Electrical Specifications Series 309 Electrical Specifications Resistance 100 to 5 Megohms, linear Linear: 5 to 5 Megohms 500 to 2 Megohms, non-linear Taper: 100 to 2 Megohms Resistance Range Linear: thru 500K, 10% 10% standard 5% special. above 500K to 5 Megohms, 20%. Trimmers 20%. Non-linear thru 100K, 10% above 100K 20% End Resistance Linear: 4 maximum each end. 2 maximum, 5 to 2500 Taper low side 4 maximum 4 maximum, 5K and above. high side 1% of total R. Power Rating .5 watt 70C. Derated linearly to zero 1 watt 85C. Derate linearly to zero watts at 150C. watts at 120C. See Figure 2, page 3 For non-linear tapered units or PC For tapered units, trimmers or PC mounting, derate by 50%. mounting, derate 50%. Trimmer style, derate by 50%. Effective Rotation 265 5 without rotary switch 250 +10 -5 without rotary switch 225 +10 -5 with rotary switch. 240 5 with rotary switch. Dynamic Noise Standard: Linear single controls Standard: Linear single controls maximum initial noise level of 3% of total resistance. maximum initial noise level of 1.5% of total resistance. Measurement made Measurement made using constant current using constant current source and source and oscilloscope detection technique. Special: 1.5% oscilloscope detection technique. Special: 1% Electrical Specifications continued, next page State Electronics 36 Route 10, E. Hanover, NJ 07936 Page 1 973-887-2550 Toll Free 1-800-688-9711 Fax 973-887-1940 Internet Electrical Specifications continued, next page 295 5 295 5 Electrical Rotation Working Voltage 350 Vdc across end terminals, 350 Vdc across end terminals, but power not to exceed rating. but power not to exceed rating. Resistance Temperature See Chart C. See Chart C. Characteristics Linearity 5% independent 5% independent Right or left-hand available. Non-linear Tapers Right or left-hand available. See Chart A. See Chart A. 20% of nominal resistance 50% Taper Tolerance 20% of nominal resistance 50% 3% of mechanical rotation 3% of mechanical rotation .008%/Volt maximum Voltage Coefficient .008%/Volt maximum. 900 Vac for 60 seconds ATM Dielectric Withstanding 750 Vac for 60 seconds ATM pressure. 350 Vac for 6 seconds Voltage pressure. 350 Vac for 6 seconds 3.4 in. Hg. 3.4 in. Hg. Series 308/309 Mechanical Specifications Mechanical Rotation Push Momentary Switch 295 5 S.P.S.T., 125ma, 28Vdc, push momentary switch. Type DJ Stop Torque Rotary Switch 3 lb. in. minimum (metal shaft) S.P.S.T. or S.P.D.T., CCW or CW, 125ma, 28Vdc. Type AL Other torque options available. Please contact Center Detent State Electronics. Indent device which provides an indexing position. Torque Range Indent torque: .6 to 3 oz. in20 to 3.0 oz. in. (Single) .3 to 3.5 oz. in. (Dual) Rotational torque: .3 to 2.5 oz. in4 to 4.5 oz. in. (Triple). Indent position: Single at 50% mechanical rotation Other torque options available. Please contact Rotational life: 25,000 cycles State Electronics. Housing Torque Variation Thermoplastic polyester, blue. (U.L. SE-O rating) Within control .5 oz. in. maximum Hardware Bushing Nut: brass, nickel-plated Material: Brass nickel plated Lockwasher: phosphorous bronze, nickel-plated Diameters: Supplied in .250 32 NEF 2A thread Solvent Resistance (6.35mm) and .375 32 NEF 2A thread Housing resistant to trichlorethylene, *Chlorethene NU, (9.53mm) Freon TMS, **Freon TMC, toluene, MEK, ethyl acetate Lengths Available in .250 (6.35mm), .375 (9.53mm), and gasoline. For solvents not listed, please consult and .500 (12.7mm). Factory. Note: Units not immersion sealed Styles: Plain, locking and trimmer Terminals Shafts Gold-coated PC terminals or solder hook style. PC pins fit Material: Brass nickel plated and stainless steel .100 grid spacing. Terminal mounting options available Diameters: Single shaft: .125 (3.18mm) and .250 (6.35mm) Weight (approx.) Concentric: .078 /.125 (1.98/3.18mm) Metal shaft & bushing: (Single) .19 oz., (Dual) .27 oz., and .125:/.250 (3.18/6.35mm) (Triple) .35 oz. Lengths: Maximum of 3 (76.2mm) from bushing mounting surface .025 (.635mm) minimum on * T.M. Dow Chemical Co. trimmer or bushing **T.M. Dupont Styles: Plain, slotted flatted and concentric Mechanical Specifications continued, next column Page 2 State Electronics 36 Route 10, E. Hanover, NJ 07936 973-887-2550 Toll Free 1-800-688-9711 Fax 973-887-1940 Internet