Digital I/O module romod 4DIO-R eco

RS485Modbus RTU4 digital inputs

Product information
The romod 4DIO-R eco is a DIN-rail mounted 4-channel digital I/O module providing four digital inputs and four relay digital outputs. It is suitable for controlling single-stage motors and digital actuators and for monitoring simple digital signals such as status or fault messages.

Digital Outputs:
Four relay outputs provide normally open (NO) contacts. Switched signals must share the same phase. Outputs can be controlled via Modbus or configured to follow digital input signals. Available functions per output include static control, toggle, configurable on/off delays, minimum ON/OFF times and mutual interlocking. All outputs can be configured with a defined safe state if valid Modbus telegrams are not received within a configured timeout.

Important:
Ensure switched signals have the same phasing. Configure the safe-state trigger time sufficiently long to avoid unintended activations in case of remote device failures or bus timeouts.

Digital Inputs:
Digital inputs are driven by 24 V through external dry contacts connected to the module terminals. The reference potential is set via the COM terminals and may be 0 V or 24 V, allowing control by either 24 V or 0 V signals. Each input can be set to normally-open or normally-closed operation via Modbus registers. Inputs support counting for DC pulses (not retentive across power loss); minimum pulse width for reliable detection is 10 ms. For AC-driven inputs, edge detection can be delayed using configuration registers. A status register reports which DI changed since last read; reading the register resets its bits.

Technical data
Power supply: 24 V AC/DC, terminal connection
Current consumption: typically 68 mA (DC), 152 mA (AC) with all relays energized
Power dissipation: max. 1.7 W (DC), 3.7 W (AC) with all relays energized
DO specification: Relay outputs (NO), max. 250 VAC; Rated load 3 A at 250 VAC / 30 VDC; Max. switching voltage 277 VAC, 30 VDC; Max. switching capacity 830 VA (AC), 90 W (DC); Initial contact resistance ~100 mOhm (at 1 A / 24 VDC); Endurance 100,000 operations (rated load). Inductive loads should be avoided or suppressed at source.
Counting: pulse min. 10 ms (DC only); max. counter value 4,294,967,296; counter values are not stored after power loss.
Bus interface: RS485, Modbus RTU; supported baud rates (autobauding): 9,600; 19,200; 38,400; 57,600 Baud; serial parameters: 8-N-1
Configuration memory: internal EEPROM, up to ~100,000 write cycles
Environment: operating temperature 0...50 °C; storage/transport 0...70 °C; relative humidity 10...90% non-condensing; protection class IP20

Specifications

• Model: romod 4DIO-R eco
• Function: 4 digital inputs, 4 digital outputs (relay, NO contacts)
• Relay rating: 3 A at 250 VAC / 30 VDC
• Max switching voltage: 277 VAC, 30 VDC
• Max switching capacity: 830 VA (AC), 90 W (DC)
• Initial contact resistance: approx. 100 mOhm (at 1 A / 24 VDC)
• Endurance: 100,000 operations (rated load)
• Input counter: pulse min. 10 ms, max. value 4,294,967,296 (not retentive)
• Power supply: 24 V AC/DC
• Typical current consumption: 68 mA (DC), 152 mA (AC) with all relays activated
• Power dissipation: max. 1.7 W (DC), 3.7 W (AC)
• Bus: RS485, Modbus RTU; baud rates: 9.6k, 19.2k, 38.4k, 57.6k
• Configuration memory: internal EEPROM, ~100,000 write cycles
• Serial parameters: 8-N-1
• Operating temperature: 0...50 °C; Storage/transport: 0...70 °C
• Relative humidity: 10...90% non-condensing
• Protection class: IP 20
• Weight: 0.137 kg