JPH0669743U - Calibrator for electromagnetic flowmeter - Google Patents

Abstract

(57) [Abstract] [Purpose] It is not necessary to use an external power supply such as an AC 100 volt power supply or a battery, it is small and easy to carry, and power consumption can be saved. [Structure] An isolation transformer 5 is connected in series with impedance adjusting resistors R1 and R2, and an exciting current I from an electromagnetic flowmeter converter 4 is supplied to a primary winding of the isolation transformer 5. Then, the alternating current generated in the secondary winding of the isolation transformer 5 is transferred to the diode D1,
It is rectified by D2 and the capacitor C1 and given to the DC power supply generation circuit 6, and in the DC power supply generation circuit 6, a DC voltage E1 to the digital circuit and a DC voltage E2 to the analog circuit are produced.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electromagnetic flowmeter calibrator used for calibration such as gain adjustment and current output adjustment of an electromagnetic flowmeter converter.

[0002]

[Prior art]

 Conventionally, this kind of electromagnetic flow meter calibrator receives an AC 100 V power supply from the outside, divides this voltage by a transformer, and operates its internal circuit. FIG. 2 shows a power source generator built inside the calibrator for the electromagnetic flow meter, which divides the AC 100 volt power source from the outside through the outlet 2 with the transformer 3, and the DC voltage E1 to the digital circuit and the analog circuit. DC voltage E2 is being generated. The electromagnetic flowmeter calibrator (hereinafter, simply referred to as calibrator) 1 is used for calibration such as gain adjustment and current output adjustment of the electromagnetic flowmeter converter. That is, as shown in FIG. 3, the calibrator 1 receives an exciting current I which is periodically supplied via the X and Y terminals of an electromagnetic flowmeter converter (hereinafter, simply referred to as a converter) 4. The pseudo flow rate signal generation timing is created by applying the pseudo flow rate signal to the converter 4 via the terminals A, B, and C, and the converter 4 is calibrated. For example, when adjusting the gain of the converter 4, first, the converter 4 is placed in the gain calibration mode. Then, the calibrator 1 is set to the instructed flow velocity of the converter 4, and the output of the calibrator 1 is turned on. As a result, the calibrator 1 generates a rectangular wave voltage corresponding to the signal electromotive force of the set flow velocity as a pseudo flow rate signal, and supplies it to the converter 4 via the terminals A, B, and C. Here, if the gain calibration mode of the converter 4 is turned on, the signal electromotive force of the set flow velocity is stored in the converter 4.

[0003]

However, according to such a conventional calibrator 1, such a calibrator 1 cannot be used in a place without an AC 100-volt power supply. Also, the transformer 3 for 100 VAC was required inside, which was large, inconvenient to carry, and consumed a lot of power.

The present invention has been made to solve the above problems, and its purpose is to eliminate the need for an external power supply such as an AC 100 volt power supply or a battery, and to make it compact and easy to carry. Another object of the present invention is to provide a calibrator for an electromagnetic flow meter that can save power consumption.

[0005]

[Means for Solving the Problems]

 In order to achieve such an object, the present invention uses an exciting current from an electromagnetic flowmeter converter as a source to generate a power supply voltage for operating its internal circuit.

[0006]

[Action]

 Therefore, according to the present invention, when the electromagnetic flowmeter converter is calibrated, the excitation current that is always given from the electromagnetic flowmeter converter is received to generate the power supply voltage for operating the internal circuit.

[0007]

【Example】

 Hereinafter, the present invention will be described in detail based on embodiments.

FIG. 1 is a diagram showing a power source generator built in an electromagnetic flowmeter calibrator according to an embodiment of the present invention.

In the present embodiment, the exciting current I which is periodically supplied via the X and Y terminals of the converter 4 is received, and the comparison results of the comparators CP1 and CP2 are given to a CPU (not shown). In addition to creating the pseudo flow rate signal generation timing, the exciting current I is applied to the isolation transformer 5 to create a DC voltage.

That is, the isolation transformer 5 is connected in series with the impedance adjusting resistors R1 and R2, and the exciting current I is supplied to the primary winding of the isolation transformer 5. The alternating current generated in the secondary winding is rectified by the diodes D1 and D2 and the capacitor C1 and given to the direct current power generating circuit 6, and in the direct current power generating circuit 6, the direct current voltage E1 to the digital circuit and the direct current voltage E2 to the analog circuit are generated. Is supposed to be created.

Therefore, according to the calibrator 1'of the present embodiment, an AC 100V power source and an external power source such as a battery are not required, and the calibrator 1'is small in size, easy to carry, and power consumption can be saved.

[0012]

[Effect of device]

 As is apparent from the above description, according to the present invention, the exciting current from the electromagnetic flowmeter converter is used as a source to generate the power supply voltage for operating the internal circuit, so that the AC 100V power supply is used. Since it does not require an external power source such as a battery or a battery, it is small and easy to carry, and power consumption can be saved.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a power source generator built inside an electromagnetic flowmeter calibrator according to an embodiment of the present invention.

FIG. 2 is a diagram showing a power supply generation unit built inside a conventional calibrator for an electromagnetic flow meter.

FIG. 3 is a diagram for explaining a method of calibrating an electromagnetic flowmeter converter using an electromagnetic flowmeter calibrator.

[Explanation of symbols]

 1'Electromagnetic flowmeter calibrator 4 Electromagnetic flowmeter converter 5 Isolation transformer 6 DC power supply generation circuit D1, D2 Diode C1 Capacitor

Claims (1)

[Scope of utility model registration request] 1. An electromagnetic flowmeter that receives an exciting current from an electromagnetic flowmeter converter to generate a pseudoflowrate signal generation timing, and gives a pseudoflowrate signal to the electromagnetic flowmeter converter to calibrate the electromagnetic flowmeter converter. A calibrator for an electromagnetic flowmeter, comprising: a calibrator for a flowmeter, comprising a power supply voltage generating means for generating a power supply voltage for operating an internal circuit thereof by using the exciting current as a source.