CS238803B1 - Measuring device for checking of electric parameters of transformator and of electronic units - Google Patents

Abstract

The invention addresses a method of automatic measurement electric unidirectional, alternating voltage, current and insulation quantities state. The essence of the invention is conventional replacement measuring instruments with the device with electronic evaluation and optical-acoustic level signaling quantity.

Description

BACKGROUND OF THE INVENTION The present invention relates to a measuring device for checking the electrical parameters of transformers and electronics units which enables automatic measurement and evaluation of electrical parameters.

There are known devices enabling automatic measurement of direct current voltages and currents, or measuring centers for measuring direct current voltages and currents with digital output. Costly converters are required to measure AC values. Said devices do not allow simultaneous control of the insulation with the applied high voltage and currents which do not have a sinusoidal waveform as required to control the electrical parameters of the mains transformers.

The principle of measuring equipment for checking the electrical parameters of transformers and electronics units depends on the output of the measured object and the output of the high-voltage source being connected to the input of the high-voltage switch block whose output is connected through the measuring point block and the digital converter block to the current and block comparators whose output is fed through the shaping block to the evaluation block.

The advantage of the device according to the invention is the replacement of the measurement by the hand-held measuring instruments, automatic measurement with electronic evaluation of the level of direct and alternating voltages and currents, checking the insulation strength of the measured object with one measuring object connection by the measuring device.

An exemplary embodiment is shown in the block diagram of the measuring device.

The measured object 1 by means of the block 2 of the high-voltage switch is connected to the block 3 of the measuring points. The high-voltage switch block 2, when checking the insulation with the applied high voltage, connects the object 1 to be measured through the high voltage breakdown indication block 17 and the high voltage switching block 18 to the high voltage source 15. When measuring current and voltage, the measured object 1 is separated from the high voltage circuit by means of the high voltage switch block 2 and connected to the power supply block 22 and the measuring point block 3 which connects the measured object 1 in unidirectional quantities directly to the digital converter block 5 or by means of transformer 4 to block 5 of a digital converter when measuring AC values. When measuring unidirectional or periodic sinusoidal quantities, the output from the 5-digit converter block is directly connected to the comparator block 6. When measuring the non-sinusoidal waveform, the intermediate converter 5 of the digital converter and the comparator block 8 are connected with the current measurement block 18. The measurement accuracy tolerance is set from a comparator block 6 from a reference voltage source 19. The output of the comparator block 6 is connected via the shaping block 7 to the evaluation block 8. A comparison pulse block 20, a control pulse block 12, and a high voltage breakdown indication block 17 are connected to the evaluation block 8. The output of the evaluation block 8 is connected to the stop block 10 and the evaluation panel 9. The output from the stop block 10 is connected via the control generator block 11 to the input of the control pulse block 12 which is connected to the high voltage source 15, the digital converter block 5, the measuring point block 3, the evaluation panel 9, the shift register block 13. The output of the shift register block 13 is connected to the measuring point block 3 and the diode matrix block 14. The output from the diode matrix block 14 is connected to the high voltage switching block 16, the high voltage source 15, the measurement point block 3, the digital converter block 5, the high voltage switch block 2, the current measurement block 18 and the reference voltage source 19. The metering device comprises a stabilized voltage source 21, which is supplied from the ground controller block 22. The output from the network controller block 22 is connected to a high voltage source 15. The output of the stabilized voltage source 21 is coupled to a comparative pulse block 20.

The measured object 1 is connected to the block 2 of the high-voltage switch, which galvanically separates the high-voltage circuits from the low-voltage circuits. The outputs from the high-voltage switch block 2 'are connected to the measuring point block 3, which in the sequence of time connects the individual measuring points of the measuring point block 3 via the isolation transformer 4 to the digital converter block 5. It is a digital-to-voltage binary voltage reader with voltage reading which, according to the program stored in the diode matrix block 14, sets a suitable conversion such that at any correct voltage measurement the output from the digital converter block 5 has a constant value. The measuring point block 3 determines the number of measurements per measurement cycle and is controlled by the diode matrix block 14. The switching sequence of the switching point block 3, the digital converter block 5, the shift register block 13, the high voltage source 15 determines the control pulse block 12, which is controlled by the control generator block 11. The output voltage of the digital converter block 5 is applied to the input of the comparator block 6 comprising the upper and lower level comparators. The upper and lower limits of the measurement are determined by the reference voltage source 19. Outputs from the comparator block 6 are fed to the evaluation block 8 via the shaping block 7. In case the measured voltage lies within the measurement tolerance value, the output from the evaluation block 8 optically indicates the correct level in the evaluation panel 9. If the measured voltage level is higher or lower than

With the measured voltage tolerance, the evaluation block 8 indicates on the evaluation panel 9 a high or low level at which the stop block 10 blocks the control generator block 11 and the optical indication of the shift register block 13 determines which step of the measured cycle is outside the measurement tolerance range. The last steps of the measuring cycle are measurements of the insulating strength of the measured object 1 by the applied high voltage. When measuring the insulation strength, the high voltage switch block 2 disconnects the circuits of the measured object 1 from the measuring point block 3 and connects them through the high voltage breakdown indication block 17 to the high voltage switching block 16 which switches the program outputs from the dicdic matrix 14 high voltage source 15. At the high voltage breakthrough, the high voltage breakthrough indication block 17 on the panel 9 indicates an optically acoustic high voltage breakthrough evaluation when the measuring cycle step is blocked.

The device can be used in semi-automatic and automatic lines for checking electronic equipment, for measuring voltage, current levels, transformer ratio and insulation status.

Claims (2)

SUBJECT A measuring device for checking the electrical parameters of transformers and electronics units, characterized in that the output of the measured object (1) and the output of the high voltage source {15} are connected to the input of the block (2J of the high voltage switch). and a block (6) of the digital converter to the current measurement block (18) and a comparator block (6), the output of which is INVENTED through the former (7) of the former to the evaluation block (8). 2. A measuring device for checking the electrical parameters of transformers and electronics units according to claim 1, characterized in that the high voltage switch block (16) is connected to the high voltage power supply (15) and the high voltage breakdown indication block (17).