The Model 255 digital V-A-W meter provides TRUE RMS measurements of VOLTAGE, CURRENT, and POWER. These measurements are essentially independent of the waveshape and of the power factor from DC up to frequencies of hundreds of kilohertz. Voltage and current readings are typically within 1°/o to 400 kHz for sine waves. The power in a 100 kHz square wave may normally be measured within 2%. WIDE MEASUREMENT RANGE AMPLE RESOLUTION The Model 255 provides FOUR full scale current ranges from 5 mA to 5 A, THREE full scale voltage ranges from 20 V to 1000 V., TWELVE full scale power ranges from 100 mW to 5000 W and TWELVE, increased resolution POWER X10 ranges from 10.00 mV to 500.0 W. A full four digit display provides ± 1 digits of resolution for full scale ranges corresponding to 1000, 2000, or 5000 digits. ISOLATED OUTPUTS AND PROGRAMMING The meters have optically isolated, digital options of: A. Parallel, four digit BCD output B. Remote control of FUNCTIONS C. IEEE-488 Talker/Listener Board. The meters have an optional isolated ANALOG output. One volt output for a Full Scale display reading. CURRENT OR VOLTAGE RANGE EXTENSION Full Scale CURRENT ranges down to 50.00 pA or VOLTAGE ranges down to 1.000 V or 2.000 V are possible. External broad­ band shunts or transformers allow CURRENT extension to 50.00 A or 500.0 A. External voltage dividers allow VOLTAGE extension to 3500 V. Full Scale POWER for each case is equal to the VOLTAGE X CURRENT product. M M M * ~ v < $ # # * si DEALS WITH MANY DIFFICULT MEASUREMENTS The Model 255 is ideally suited to measuring almost any non- sinusoidal and/or low power factor waveshape. Typical uses are in connection with SW ITCHING POWER SUPPLIES, TRANSFORMER LOSSES, FLUORESCENT LAMP BALLASTS, R-C FILTER RECTIFIER CIRCUITS, SCR CIR­ CUITS, MERCURY-ARC LAMP CIRCUITS, SERVO SYSTEMS, MOTOR TESTING, ULTRASONICS, MOV LOSS TESTING, AUTOMATIC TEST EQUIPMENT, SODIUM LAMP BALLASTS, FERRITE CORE LOSSES, TELEVISION SET LOSSES, AND ELECTRIC AUTOMOBILE EFFICIENCY MEASUREMENTS. EASY TO USE/HARD TO DAMAGE The Model 255 is an all solid state, digital readout instrument. The V-A-W meter is complete, self contained instrument that is easy to use, hard to damage, easy to service, and easy to maintain. LOW CIRCUIT LOADING An imput impedance of five Megohms for the VOLTAGE ter­minals coupled with a full scale voltage drop of 100 millivolts across the CURRENT terminals cause negligible circuit loading or errors in most practical cases. PACKAGING/PROTECTION The Model 255 is housed in a heavy duty aluminum case. The three lowest current range shunts are also diode and fuse pro­tected.