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DAM-8DI-8DO

DAM-8DI-8DO

RS-485 interface, 8 digital inputs, 8 digital outputs

Overview​

  • Industrial 8-channel digital input + 8-channel digital output module.
  • RS-485 interface and standard Modbus RTU protocol.
  • Bidirectional opto-isolation on the input side; supports dry contacts and active wet contacts (NPN / PNP).
  • Outputs use Darlington open-collector drive with opto-isolation; 500 mA per channel.
  • Supports linkage, cycle, toggle, delay, flash on/off, and other output control modes.
  • Dual isolation on the communication path with fuse、TVS and gas discharge tube protection.
  • Stable and reliable for demanding industrial applications.

Specifications​

ItemDetails
Power6–36 V DC
InterfaceRS-485
Baud rates4800, 9600, 19200, 38400, 57600, 115200, 128000, 256000
Default format115200, N, 8, 1
Digital outputs8 channels, 5–36 V, NPN Darlington open-collector, 500 mA per channel
Digital inputs8 channels, 5–30 V; dry contact / active input (NPN or PNP)
ProtocolStandard Modbus RTU
LEDSTA: solid on in Bootloader mode; slow blink when running; fast blink during communication
Dimensions121 × 72 × 34 mm

Hardware interface​

DAM-8DI-8DO
FunctionPinDescription
Power DC 6–36 VVCCPositive
GNDNegative
UnusedNCUnused pin; leave floating
CommunicationRS485 A+RS-485 A
RS485 B-RS-485 B
EARTHRS-485 ground / earth
Digital inputDI COMInput signal common
DGNDDigital ground
DI1–DI8Channels 1–8 digital inputs
Digital outputDO COMClamp diode anode; use with inductive loads such as relays
DGNDDigital ground
DO1–DO8Channels 1–8 digital outputs

RS-485 bus wiring​

Most PCs have no RS-485 port. Use a USB-to-RS485 adapter; connect A to the module A terminal and B to B. For multiple devices, use twisted-pair shielded cable in a daisy-chain topology.

Digital output wiring​

Outputs are NPN Darlington open-collector: connect the load between the external supply positive and the corresponding DOx; connect DGND to the external supply negative. For inductive loads, add a freewheeling diode and connect DO COM to the supply positive.
When the output is OFF, DOx is high-impedance, the load is disconnected, and the LED is off. When ON, DOx is pulled low, the load is energized, and the LED is on.

Digital input wiring​

DI1–DI8 are the 8 input channels; DGND is the signal ground. DI COM is the input common—it may be left floating, tied to supply positive, or tied to supply negative. Power may come from the module supply or an independent source.

  • Floating: dry contact (passive) input
  • Tied to supply +: low-level trigger, NPN wet / active input, 5–30 V DC
  • Tied to supply −: high-level trigger, PNP wet / active input, 5–30 V DC

Dry contact wiring
NPN active (wet) input wiring
PNP active (wet) input wiring

Operation demo​

Two tools are shown below. Either works for first bring-up; the web serial assistant is recommended for a quick start.

  • Web serial assistant: no install; full frame display and parsing; less intuitive for register data.
  • Modbus Poll: direct register access; easier to read output/input states; frames are not fully shown.
  • Open the serial debug tool, select the COM port, set 115200 N 8 1, and open the port.
  • Enable hex display and hex send, set checksum to ModbusCRC16, send 01 05 00 00 FF 00. CH1 output should turn on and echo the frame.
  • Use Module commands on the right to pick the module model and send preset commands, or expand entries to edit before sending.
  • Common commands builds Modbus function-code frames from parameters.

Resources​

Documentation​

Tools​