- Supports Sink (Wet Contact) / Counter input type - Rated Input : >5mA @ 12 VDC - Input Filter : Programmable, Default 3ms - Current : >10mA @ 24 VDC - Pulse Input Frequency : 150Hz - Over Voltage Protection : +40 VDC - -40 ~ 70°C operating temperature ADAM-3651 is a 8-ch digital input expansion module for ADAM-3600-C2G intelligent RTU.