Apartment Intercom vs Battery

Product features: ◆ Support 200 sets of numbers, each number can be set in the time period to control the relay to open the door. ◆ A relay output is used to control to open the door, connected when there is the number of incoming users , And it will automatically disconnect at set time. ◆ After a user calls to control to open the door, it can send SMS to the user about its action. ◆ 000~999 seconds, we can control the relay closing time, 000 indicates: the relay is closed for 0.5 seconds then disconnected. 999 indicates: the relay can be closed until the same number incomes again then disconnected. ◆ SMS commands can be used to query the current state of the host (relay status and GSM signal value). ◆ SMS can be regularly uploaded for the current state of the host to the first user number. ◆ Use the clock on the module, each time the host sends SMS to itself to correct the time.

This application is mainly used to test the status of automotive lead-acid batteries. It can read the real-time voltage and power of the battery, and roughly determine the internal resistance of the battery and other functions through the pressure difference of the starting voltage.