摘要 |
PCT No. PCT/DK88/00225 Sec. 371 Date Oct. 31, 1990 Sec. 102(e) Date Oct. 31, 1990 PCT Filed Dec. 29, 1988 PCT Pub. No. WO89/11083 PCT Pub. Date Nov. 16, 1989.A flowmeter comprising a thermocouple with hot and cold junctions and a current source for causing a termperature difference between the hot and cold junctions of the thermocouple. The thermocouple is connected to the current source through a controlled switch, with a control input on the switch being connected to a control device. The control device also controls a measuring circuit, which on its input port receives a signal representing the e.m.f. of the thermocouple during the periods of time when the current from the current souce to the thermocouple is interrupted by the switch. The current source and the hot and cold junctions of the thermocouple all are connectable in series by the control device through the same two conductors which are also connected to the measuring circuit. |