The temperature monitoring device is connected to the 248 temperature sensor; there is no current flow. Please advise
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When the torch is ignited, the temperature monitor experiences a jump, and the alarm set point changes automatically. We estimate that when the high-altitude igniter is activated, there is a pulsed interference with the flame detection thermocouple (the thermocouple signal wire was disconnected at the temperature monitoring device, and no shift was observed during ignition). We plan to add a 248 temperature sensor between the thermocouple and the temperature monitor. The input signal of the temperature monitoring device has been modified to 4-20mA; the measured voltage is 19.7V. After connecting it to 248, the voltage drops to 8.7V with no current flowing. Please advise! ! (There is no isolation barrier for now; it is indicated that experiments are being conducted!) ）
Draw a diagram to show how the wires are connected; otherwise it’s hard to explain.
248 temperature-sensitive series 250-ohm resistor, connected to the input terminal of the temperature monitoring device (two-wire transmitter)
My head hurts trying to figure it out; just take a look at the instructions.
4-20mA with a 250 ohm resistor in parallel converts to a 1-5V input; what does series connection mean?
“We plan to add a 248 temperature sensor between the thermocouple and the temperature monitor. The input signal of the temperature monitoring device was modified to 4-20mA; the measured voltage was 19.7V. After connecting it to 248, the voltage dropped to 8.7V with no current flow. When connected to 248, the voltage remains at 8.7V – can the 248 temperature sensor still function? You also used a \"248 temperature-sensitive resistor in series with a 250-ohm resistor, connected to the input terminal of the temperature monitoring device.\" The power supply provided by that temperature monitoring device is not strong enough to drive the 248 temperature-sensitive resistor, so naturally no current flows.