Datakom DKM-409 PRO AT User Manual

Datakom DKM-409 PRO AT User Manual Manual pdf 17 page image

DKM-409 Pro AT User Manual Rev_02 Firmware V-2.5Structure: Relay output, normally open, free contact outputMax switching current: 5A @250VACMax switching voltage: 250VACMax switching power: 1250VAStructure: RS-485, isolated.Connection: 3 wires (A-B-GND). Half duplex.Baud rate: 2400-115200 bauds, selectableData type: 8 bit data, no parity, 1 bit stopTermination: External 120 ohms requiredCommon mode voltage: -0.5 VDC to +7VDC, internally clamped by transient suppressors.Max distance: 1200m @ 9600 bauds (with 120 ohms balanced cable)200m @ 115200 bauds (with 120 ohms balanced cable)Isolation: 500VAC, 1 minuteThe RS-485 port features MODBUS-RTU protocol. Multiple modules (up to 128) can be paralleled on thesame RS-485 bus for data transfer to automation or building management systems.The RS-485 port provides also a good solution for distant PC connection where RainbowPlus programwill enable programming, control and monitoring.RS-485 BUS STRUCTUREA maximum of 32 devices can be paralleled on a RS-485 bus. For more devices on one bus, repeatersmust be used.The bus must be terminated from both ends with 120 ohm resistor.The cable shield should be grounded from one end only.A B A B A BA B120R 120R3.5. RELAY OUTPUTS3.6. RS-485 PORTThe Modbus register list is available at the MODBUSsection of this manual.The device does not have any internal terminatingresistors. External 120 ohm resistor should be addedto both extremities of the bus line.