ژول متر ( انرژی سنج ) دیجیتال ساخت Philip Harris انگلستان
Philip Harris Digital Joulemeter
• Determine specific heat capacity of metal
• Measure the enthalpy changes of reactions taking place in a solution
• Investigate the efficiency of energy conversion
• Meter output sockets for display of watts
This accurate electronic joule and wattmeter, usable with both alternating and direct input voltages, can be used to measure the energy supplied to electric heaters in calorimetry experiments and for energy conversion investigations when it is required to compare the input and output energies of motors and dynamos. At a more advanced level it can be used to measure the energy stored in a capacitor. It can also be used to show that maximum power is dissipated when the source and load resistance are equal, and that no power is dissipated in a purely reactive load. An oscilloscope may be used to compare the input voltage and the instantaneous power dissipation; and to demonstrate the difference between average and peak powers, and the effect of phase angle variation. The instrument has four internal shunts to give maximum current ranges of 0.7mA, 7mA, 0.7A and 7A a.c. with a max. input of 15V (the maximum input power can be doubled when used on d.c.; the maximum voltage then being 20V d.c. with corresponding current maxima of 1mA, 10mA, 1A and 10A).
Each input current range has three joule ranges selected by a slide switch.
• Input voltage: 0 to 15 a.c. (21V d.c.).
• Input resistance: 1MΩ.
• Input frequency: d.c. or 50 to 1000Hz a.c.
• Max. load current: 0.7mA, 7mA, 0.7A and 7A.