Test unit for subscriber call meter circuit

Abstract

Abstract PURPOSE:To obtain a subscriber call meter circuit test unit which is capable of a high-accuracy test for both the breaking and the contact of the subscriber circuit in which the subscriber relay and the subscriber call meter circuit are connected in series and with connection to the negative power source at the subscriber relay side and to the ground at the subscriber call meter circuit side respectively. CONSTITUTION:The test unit comprises the following parts: detection part 1 where the busy state of tested subscriber circuit 10 is detected via operation of the SBY key; reference equivalent circuit part 2; detection part A.3 provided in opposition to circuit 10; detection part B.4 provided in opposition to part 2; detection part C.5; detector A.6 which detects the difference of the voltage drop detected at part A.3 and B.4; detection part B.7 where the difference of the voltage drop is detected between the value detected at part A.3 and part B.4+C.5; decision display control part 8 where the difference is analyzed between the voltage drop detected at part A.6 and B.7 plus the decision of circuit 10, the display of the dicision result and the control of the test progress are given each; and power supply part 9 respectively.

Inventors

• 👤 Isao Matsumoto
• 👤 Eizo Tateyama
• 👤 Shigeru Okazaki
• 👤 Masakazu Hotta

Bibliographic Details