DI-904MB/DI-905MB/DI-906MB
Multi-Channel Discrete I/O Modules
Active-High Inputs Sourcing Outputs (High-Side Switching)

- Standard Modbus RTU protocol with high-speed RS-485 communication (up to 115K bps)
- Twelve I/O channels in a single inch-wide unit reduces system costs and saves panel space
- High-voltage, high-current, open-source outputs enable direct (high-side) control of external devices
- High-voltage buffered inputs monitor discrete levels from a variety of industrial devices
- Tandem input/output circuitry (DI-906MB models only) connects input buffers with open-source outputs for convenient loopback monitoring of the output state
- Watchdog timers provide a configurable failsafe output state for use when host I/O communication is lost
- Three-way isolation eliminates potential ground loops between power, I/O, and network circuitry
- Self-diagnostics monitor microcontroller activity to detect operational failures (lock-up) and execute a reset to restore communication.
For complete specifications, download the Data Sheet (pdf) or the Manual (pdf).
| Part # | Price | Order |
| DI-904MB Input Module |
$286 | |
| DI-905MB Output Module |
$285 | |
| DI-906MB I/O Module |
$310 |
Note: Pricing outside the U.S. will be higher to account for shipping, taxes, duty, currency fluctuation, local warranty and technical support in your country. DI-900MB modules have typical lead times of 1-2 weeks.
Product Highlights
These modules provide twelve discrete input and/or output channels. Isolation separates the I/O, power, and network circuits. Network communication adheres to the industry-standard RS-485 Modbus RTU protocol. Both AC and DC power sources are supported with wide range, nonpolarized, diode-coupled terminals.
The outputs are intended for current-sourcing or high-side switching applications. The buffered inputs are active-high. These models are the complement of the DI-901MB, DI-902MB, and DI-903MB units which have low-side output switches and active-low inputs. Socketed pull-down resistors are easily removed or exchanged to satisfy your application requirements. See the Circuit Connection Diagrams.
Combining flexible I/O types, wide I/O ranges, and a network interface in a single package, makes this instrument extremely powerful. Multi-channel design adds cost-efficiency and allows high-density mounting. Plus, safe, rugged construction makes these modules reliable for use in both control room and distributed field I/O applications. Custom module configurations are also possible (consult factory for details).
Everything you need to complete your network is available from DATAQ Instruments, Inc. - isolators, signal converters, signal boosters, power sources, and mounting hardware. Check out the Accessories.
Specifications
904MB - Discrete Input Module
(Active-High)
Input: 12 channels, 0 to 35V DC range
Power: 10 to 36V DC, 24V AC
Network Communication: Modbus-RTU high-speed RS-485
905MB - Discrete Output Module
(High-Side Switching)
Output: 12 channels, 0 to 35V DC range, sources current
Power: 10 to 36V DC, 24V AC
Network Communication: Modbus-RTU high-speed RS-485
906MB - Discrete I/O Module
(Active-High Inputs, High-Side Switches)
Input: 12 channels, 0 to 35V DC range
Output: 12 channels, 0 to 35V DC range, sources current
Power: 10 to 36V DC, 24V AC
Network Communication: Modbus-RTU high-speed RS-485