Application, Measurement & Test of Industrial Manual Controlling Devices (Relay, Magnetic Contactor). Play With NO & NC Contact. - Automation School | PLC, HMI, SCADA & VFD Training in BangladeshApplication, Measurement & Test of Industrial Manual Controlling Devices (Relay, Magnetic Contactor). Play With NO & NC Contact. - Automation School | PLC, HMI, SCADA & VFD Training in Bangladesh