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AC SoftStart PCB

The AC SoftStart board is designed to eliminate current spikes and shocks that occur when turning on AC power receivers that have large internal capacitors, like power supplies

The board monitors the voltage of a single or three-phase AC input, upon receiving the command to turn on the channel, the microprocessor delays the process until the sine crosses zero, and only then will it switch the channel on. Zero-Cross technology is used when the relay is switched on, so a minimum current flows at the moment when the relay contacts touch each other.

The board compensates for the delay of the relay’s mechanical contacts.

This board solves the problem of when several power supplies must be switched on at the same time and when because of very high starting currents (Inrush Current), it is necessary to use a circuit breaker whose operating / protection current exceeds the power supply current by a lot, which results in the circuit breaker protection function failing to be effective.

The protection mechanism can be activated when the loads are automatically disconnected, if the mains voltage becomes unstable, it will automatically switch on again making the mains  voltage stable again.

A mini USB connection with the ability to control relays via a serial port 

The soft starter does not limit the maximum number of start cycles per hour.

Technical data

Number of channels 8
AC circuit power supply single-phase or three-phase
Total switching current  (8 relays of 16A each)
Load switching delay after switching on 500-1000ms
Protection against unstable AC  yes
AC OK monitoring indicator yes
Fault indicator yes
DC power indicator yes
DC Power supply 10-14v or 20-28v DC 
DC current consumption 25-500ma *
USB standard USB 1.1 / USB 2.0
Low speed / Full speed
USB supported operating systems Windows, Linux, Android OTG, iOS

* Current consumption depends on the number of relays switched on


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