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Member #469851

Member Since: September 15, 2013

Country: United States

  • It is there most likely in cases where the relay is being triggered by a microcontroller, as when the microcontrollers effectively turn “off” a load, they actually send signal 0 which to the microncontroller is ground - 0 v. So it simply reverses polarity in the 5V circuit, this could cause damage to the solid state relay, so the diode prevents this from being a problem since current can only flow in the correct direction with the diode in place.

No public wish lists :(