Q1: What's the use of the DI mode of GPIO interface on UC51x?

Answer: DI mode can be used to detect the real value status to know if valve control takes effect. This requires the solenoid valve has a status interface to connect to this GPIO.

Q2: What's the difference of UC3422 and UC300? Is it possible to use the same MQTT configuration file to setup MQTT connection?

Answer: The main differences are interface type and amount, UC3422 has 1*DI + 1*DO + 2*AI interfaces, UC300 has 4*DI + 2*DO + 1*RS232 + 1*RS485 + 4*AI + 2*PT100. As for MQTT, you can use the same MQTT configurations.

Q3: How to add SMS control number with "+" on UG300-4G? Is it possible to send customized SMS message to achieve control via IF-THEN commands?

Answer: Not need to add "+", the format is "area code + phone number". For example, 86xxxxxx. As for IF-THEN command, it doesn't support customized SMS message control.

Q4: Does UC300 support to keep recording pulses even when power connection is cut?

Answer: No, the data will lose if power failure. You can select UC50x which has equipped batteries to store data even device is powered off.

Q5: Is it possible to add Slave ID in the uplink payload for UC100? Does it support to set Channel Quantity as 2? Does UC100 support to read out more than 16 addresses?


  1. No, it doesn't support to upload Slave ID.

  2. No, it doesn't support to modify channel quantity. It's fixed as 1.

  3. It's recommended to apply Modbus bridge feature as it doesn't have quantity limitation. Besides, it's suggest to set spreading factory to SF7 to avoid packet missing.

Q6: If I connect an external 12V-power supply on UC502, will it use external 12V-power supply firstly, then use built-in Li-SOCI2 battery after removing the external power supply? Is it possible to replace UC502 battery with chargeable battery and charge the battery via 12V-power supply? Is it possible to increase GPIO output current when connecting external power supply?


  1. Yes, UC502 will use external power supply firstly.

  2. It supports to replace the battery, but the battery life can't be guaranteed. Besides, it can't be charged by external power supply.

  3. No, the current output by GPIO is discharged through the capacitor and the battery will not affect the output current.