| 摘要 |
FIELD: measurement equipment.SUBSTANCE: heat-dependent technological resistor Ris installed into a diagonal of bridge circuit power supply, the rating of which is higher than possible values of a compensating heat-dependent resistor R. In parallel to the resistor Rthey install a link. They measure initial unbalance and output signal of the sensor under normal temperature t, and also temperature t, corresponding to upper limit of working range of temperatures, and t, corresponding to lower limit of the working range of temperatures. On the basis of performed measurements they calculate temperature coefficient of frequency (TCF) of strain gauges of a bridge circuitandat temperatures tand t, accordingly, and also non-linearity of TCF of strain gauges of the bridge circuitThey measure input resistance of a sensor bridge circuit. A heat-independent resistor R=0.5·Ris connected. They measure initial unbalance and output signal of the sensor at temperatures t, tand t. On the basis of completed measurements they calculate TCF of input resistance at tand t. The resistor Ris disconnected, and the link is removed off the resistor R. They measure initial unbalance and output signal of the sensor at temperatures t, tand t. On the basis of completed measurements they calculate TCF of a process heat-dependent resistor Rat temperatures tand t. If TCF of strain gauges of the bridge circuit and its non-linearity belong to the area of method application, they calculate the rating of the heat-dependent resistor Rheat-independent resistor Rwith usage of produced values of TCF of strain gauges of a bridge circuit, TCF of input resistance and TCF of the technological heat-dependent resistor. The technological heat-dependent resistor Ris replaced with a resistor Rby means of partial engagement. A resistor Ris shunted with a heat-independent resistor R.EFFECT: increased accuracy of compensation of multiplicative temperature error with account of negative non-linearity of temperature characteristic of an output signal of a sensor with usage of widely distributed measurement equipment.2 cl |
