JPS5572848A - Controller for hardness tester - Google Patents

Controller for hardness tester

Info

Publication number
JPS5572848A
JPS5572848A JP14652078A JP14652078A JPS5572848A JP S5572848 A JPS5572848 A JP S5572848A JP 14652078 A JP14652078 A JP 14652078A JP 14652078 A JP14652078 A JP 14652078A JP S5572848 A JPS5572848 A JP S5572848A
Authority
JP
Japan
Prior art keywords
voltage
motor
hardness
constant
solution
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP14652078A
Other languages
Japanese (ja)
Inventor
Shozo Kasai
Tsutomu Okayama
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP14652078A priority Critical patent/JPS5572848A/en
Publication of JPS5572848A publication Critical patent/JPS5572848A/en
Pending legal-status Critical Current

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  • Tests Of Circuit Breakers, Generators, And Electric Motors (AREA)

Abstract

PURPOSE: To measure accurately hardness without providing a constant voltage circuit by detecting a load voltage by a voltage detection circuit parallel to a motor, which measures the hardness of a solution by turning blades in the solution, by driving the motor by a constant voltage by comparing its terminal voltage with a set voltage.
CONSTITUTION: Transistor 28 connecting to rectifier circuit 27 is controlled through comparing amplifier 32 applied with a voltage across motor 30 through voltage detecting resistance 31 in series to current detecting resistance 29 and a voltage from reference voltage source 33 to hold the across voltage of motor 30 constant, thereby driving motor 30 by the constant voltage without using a constant voltage circuit. Then, blades in a solution are rotated by motor 30 and the load voltage equivalent to solution hardness is detected voltage detector 35 connected in parallel to motor 30. Consequently, highly-precise measurement of hardness can be attained without using any constant voltage circuit.
COPYRIGHT: (C)1980,JPO&Japio
JP14652078A 1978-11-29 1978-11-29 Controller for hardness tester Pending JPS5572848A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP14652078A JPS5572848A (en) 1978-11-29 1978-11-29 Controller for hardness tester

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP14652078A JPS5572848A (en) 1978-11-29 1978-11-29 Controller for hardness tester

Publications (1)

Publication Number Publication Date
JPS5572848A true JPS5572848A (en) 1980-06-02

Family

ID=15409500

Family Applications (1)

Application Number Title Priority Date Filing Date
JP14652078A Pending JPS5572848A (en) 1978-11-29 1978-11-29 Controller for hardness tester

Country Status (1)

Country Link
JP (1) JPS5572848A (en)

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