2304, Electrical Resistance Testing

The operation of the measuring section of the RESISTOMAT® model 2304, 2305 high-precision inspection and test unit is based on an upgraded 4-wire design. It measures not only the voltage drops with injected current across the test object but also across an internal reference resistor. The quotient is calculated from both voltage drops. The resistance of the test object is calculated by multiplying this with the characteristic value of the reference resistor.

Apart from eliminating the error of contact layer and contact resistance, this method has the advantage that errors reduce to the quality of the internal reference resistors alone. The deviations in these reference resistances are well known and accounted for the multiplication.

The result is that the resistance of the test object can be determined very quickly and accurately irrespective of the resistances present in the current circuit.

In order to meet high standards in measuring and testing requirements the device was equipped with an integrated high-resolution A/D converter with particularly low linearity deviations. The test objects are measured at both poles, thus eliminating parasitic thermal e.m.f. voltages.

The quotient measuring method used, with constant comparison function automatically ensures zero point calibration. Thus an optimum measuring accuracy is guaranteed.

The unit features an extensive standard software for storing measured cooling curve values, temperature compensation, classification, statistical functions, printer and interface drivers, clock, line frequency adaption.

Two microprocessors ensure optimum and exact measuring and testing. For PC user the device software 2304-P001 is available.