1. Temperature and isolation series dual input corresponding function increases current by 0.01A and power increases by 0.3W. The dual input function of the power distribution series increases the current by 0.02A and the power by 0.5W. The isolated safety barrier single input corresponding function increases the current by 0.01A and the power by 0.3W.
2. For temperature transmitters, isolators, distributors and other products, multiply the current consumption by the total amount, plus the remaining amount of 30% or more to determine the rated output power of the power supply.
3. When centralized power supply and large-scale installation, in order to facilitate debugging and maintenance, it is recommended to install one power switch for each and at least no more than 10 products.
4. For AC 220V power supply products, you can refer to the above input power. Since it does not involve the problem of selecting the power supply power, you only need to select the appropriate power fuse.
Common fault trouble-shooter
First, the power light does not light or LCD does not display
1, check the instrument power supply access is correct and reliable.
2, check the supply voltage is normal.
3, check the positive and negative 24V power supply is reversed
Second, the output signal
1, the input signal is correctly connected to the input terminal.
2, the input signal type is consistent with the type of instrument input.
3, the output terminals are tightened.
4, removable external terminals are plugged in place.
5, the external output circuit is open.
Third, the output value deviation
1, positive and negative thermocouple input is reversed.
2, the three-wire RTD input method is correct.
3, the output of the positive and negative polarity is reversed.
4, the current output, the total external load resistance is greater than 500 ohms (4-20mA output).
5, the voltage output, the external load resistance is less than 200 kilohms.
6, the power supply voltage is too low.
Fourth, the output signal is unstable
1, check the wiring is solid.
2, check the input signal is stable.
3, check the output circuit wiring is reliable.
4, check the environment around the instrument whether there is high-power electromagnetic equipment.