MP312

MP312 and MP330 Power Film Resistors Type MP Chassis Mounted Power Film Resistors are made with Micronox® resistance films fired onto a ceramic substrate which is thermally bonded to an anodized aluminum base. By mounting this assembly directly to a metal surface for improved heat transfer, the high power capabilities of these unique r esistors can provide increased packaging densities in many types of electronic equipment. The special performance features of these Type MP Chassis Mounted Power Film Resistors include: Chassis Mounted Precision Power Film Resistors with Center Screw Mounting • Two case sizes that provide 15 Watt and 30 Watt ratings. • Operation up to 275°C. • Single screw mounting to simplify attachment to the chassis or other heat • A molded silicone case that encapsulates the resistor assembly to meet • Extended life stability better than 0.01% per 1,000 hours has been stringent environmental specifications. demonstrated through a 5 1/2 year, 50,000 hour program of continuous load life testing. High WattMax. Dielect. age † Voltage Strength Temp TC †† Resistance Min. Dimensions in inches and (millimeters) conducting surface. Specifications: Resistance Tolerance: ±1% (other tolerances on special order). Insulation Resistance: 10,000 Megohms min. Terminal Strength: Mil-Std-202, Method 211, Cond. A (Pull Test) 5 lbs., and Cond. B (Bend Test), ΔR 0.2% max. or 0.2 ohm max., whichever is greater. Thermal Shock: Mil-R-39009, ΔR 0.5% max. or 0.2 ohm max., whichever is greater. Momentary Overload: 2 times rated power with applied voltage not to exceed 1.5 times maximum c ontinuous operating voltage for 5 seconds, ΔR 0.5% max. or 0.2 ohm max., whichever is greater. Moisture Resistance: Mil-Std-202, Method 106, ΔR 0.5% max. or 0.2 ohm max., whichever is greater. Load Life: Mil-R-39009, 1,000 hours at rated power, ΔR 1% max. or 0.2 ohm max., whichever is greater. Power rating dependent upon chassis area. See power rating graphs. Shock, Medium Impact: 5 0G, Mil-Std-202, Method 205, Cond. C. Vibration, High Frequency: M il-Std-202, Method 204, Cond. B, ΔR 0.2% max. or 0.2 ohm max., whichever is greater, through shock and vibration sequence. Terminals: Gold Plated Solder Lugs. D - HOLE FOR MOUNTING CADDOCK 100 MP 312 15 W Model No. Max. A B C D MP 312 15 300 450 600 50 10 Ω 200 K .600 (15.24) .850 (21.59) .188 (4.78) .185 (4.70) .092 (2.34) .142 (3.61) MP 330 30 1,000 50 10 Ω 200 K .250 (6.35) .250 (6.35) † MP312 15 Watt power rating based on chassis mounting on a 6" X 4" X 2" X .040" aluminum chassis, MP312 free air rating is 2.5 Watts at 25°C. MP330 30 Watt power rating based on chassis mounting on a 7"X 5" X 2" X .040" aluminum chassis, MP330 free air rating is 5.0 Watts at 25°C. RATED LOAD, % †† TC: 50 ppm/°C referenced to +25°C, ΔR taken at +150°C and +275°C. (Low temp. TC will be nominally -85 ppm/°C at -55°C. See typical R-T curve.) 100 80 40 20 0 25 DERATING CURVE 2 1 0 -1 TYPICAL R-T CURVE %∆R 60 75 125 175 225 275 -55 0 50 100 150 200 250 AMBIENT TEMPERATURE, °C TEMPERATURE, °C Stacked Type MP Power Film Resistor Assemblies Stacked Type MP assemblies - constructed by bolting resistors between aluminum heat dissipating plates - provide a simple means of further improving packaging densities. These charts of power ratings versus air flow and chassis area show the high power levels that can be achieved with forced air cooling and with convection cooling in either vertical or horizontal orientation. FOR STACKED MP312 POWER RESISTORS POWER RATING POWER RATING FOR CHASSIS MOUNTED SINGLE RESISTORS 30 25 Data is for 25°C still air at 1 atmosphere. Chassis material: Aluminum, .040" thick. 1% WATTS/EACH RESISTOR 18 16 14 12 10 8 6 4 2 WATTS Data is for 25°C air at 1 atmosphere, ducted around resistors in the stack with 2" x 2" x .04" aluminum plates between resistors. To derive total airflow required for stack, multiply airflow/each resistor by the number of resistors in the stack. Ducting is not required when designing for convection. 20 15 Mo l de No .M 30 P3 40° ±3° C CONVECTION COOLING PLATES IN VERTICAL PLANE CONVECTION COOLING PLATES IN HORIZONTAL PLANE B A 10 5 0 312 . MP el No Mod B 2 0 .2 .3 .4 .7 1 2 34 7 10 20 30 AIR FLOW (CFM)/EACH RESISTOR 1 2 4 6 10 20 40 60 100 ALUMINUM BASE CHASSIS AREA (SQ. IN.) DIMENSIONS IN INCHES AND (MILLIMETERS) Applications Engineering 17271 North Umpqua Hwy. Roseburg, Oregon 97470-9422 Phone: (541) 496-0700 Fax: (541) 496-0408 © 2004 Caddock Electronics, Inc. CADDOCK e-mail: caddock@caddock.com • web: www.caddock.com For Caddock Distributors listed by country see caddock.com/contact/dist.html Sales and Corporate Office 1717 Chicago Avenue Riverside, California 92507-2364 Phone: (951) 788-1700 Fax: (951) 369-1151 28_IL123.1004