The Allen-Bradley 1790D-8BV8V belongs to the CompactBlock LDX family. This module serves as a base or expansion unit. It gives you 8 universal input points. You also get 8 sinking output points. The module operates on a 24V DC nominal supply. Inputs accept both sinking and sourcing field devices. Outputs are sinking type only. Additionally, the 1790D-8BV8V supports DeviceNet communication. Photocoupler isolation protects the logic side from field noise.
The 1790D-8BV8V offers 8 nonisolated input points. Each point works as sinking or sourcing. The on-state voltage ranges from 9.6V DC minimum to 28.8V DC maximum. Nominal voltage is 24V DC. On-state current reaches 8 mA maximum per point at 28.8V DC. Off-state voltage stays at 5V DC maximum. Input impedance is 4.8 kOhms nominal. Eight green status indicators show input activity. The common type is 8 points sharing 8COM. This configuration has no polarity requirement.
This module provides 8 nonisolated sinking outputs. The on-state voltage ranges from 10V DC minimum to 28.8V DC maximum. Nominal voltage is 24V DC. Maximum voltage drop is 0.5V DC. Minimum on-state current per channel is 1 mA. Off-state leakage stays below 0.5 mA. Output signal delay is 0.5 ms maximum for off-to-on. On-to-off delay reaches 1.0 ms maximum. Eight green status indicators show output status. Each output handles 0.5A maximum. The common rating is 4.0A maximum per 8COM.
The 1790D-8BV8V draws its logic power from DeviceNet. The nominal supply voltage is 24V DC. Operating range goes from 11V to 28.8V DC. Maximum power dissipation is 1.2W at 28.8V DC. Field power also requires 24V DC nominal. Its range covers 10V to 28.8V DC. Field power dissipation is 6 mA per point at 28.8V DC.
For isolation, the module uses photocouplers. Isolation exists between I/O and logic. The isolation voltage rating is 1250V AC rms. However, DeviceNet to logic is nonisolated. DeviceNet power is also nonisolated. Keep this in mind when designing your system. Wiring connects through a 37-pin D-shell connector.
The 1790D-8BV8V has sinking outputs. This means the output switches the DC common side. Your load connects between the output terminal and +24V DC. Current flows from the load into the output. Then it goes to DC common. Use this module with sourcing field devices. For example, relays with one side wired to +24V DC work well. Do not use this module with sinking field devices. That would require a sourcing output type like the 1790D-8BV8B.
The 1790D-8BV8V has a compact footprint. It mounts directly on a DIN rail. Operating temperature ranges from 0°C to 55°C. Storage temperature goes from -40°C to 85°C. Relative humidity stays between 5% and 95% non-condensing. Vibration resistance is 5g from 10 to 500Hz. Shock resistance is 30g for 11 milliseconds. The enclosure has an open type rating. You must install it inside a control cabinet.
Mount the 1790D-8BV8V on a standard 35mm DIN rail. Ensure proper orientation with terminals facing outward. Use a 37-pin D-shell cable for field wiring. We recommend pre-assembled cables from Rockwell. Strip wires to 6mm length for terminal blocks. Tighten screws to 0.5 Nm torque. Connect 24V DC field power to the designated terminals. Ground the DeviceNet cable shield at one point only. Do not run high voltage wires near the module. Maintain at least 50mm separation from power cables.
The module automatically detects input type. You do not need jumpers for sinking or sourcing configuration. Outputs are sinking only. Therefore, your loads must connect between +24V DC and the output terminal.
Allen-Bradley 1790D-8BV8V CompactBlock LDX module (1 unit)
Built-in DeviceNet communication interface
37-pin D-shell female connector (attached to module)
DIN rail mounting clip (pre-installed)
Quick start installation sheet
*Note: DeviceNet cables, 37-pin D-shell mating connectors, and power supplies are sold separately.*
We ship all I/O modules within 24 hours. Your 1790D-8BV8V will travel via FedEx, UPS, or DHL. Each package includes foam padding for shock protection. Tracking information is sent to your email address. Delivery typically takes 3-7 business days worldwide.
1. What is the difference between 1790D-8BV8B and 1790D-8BV8V?
The 1790D-8BV8B has sourcing outputs. The 1790D-8BV8V has sinking outputs. Input sections are identical on both modules. Choose based on your field device wiring requirements.
2. Can the 1790D-8BV8V accept both sinking and sourcing inputs?
Yes. The input section is universal. It accepts both sinking and sourcing field devices automatically. No configuration jumpers are needed.
3. What is the maximum output current per channel?
Each output handles 0.5A maximum. The total per common (8COM) is 4.0A maximum. Exceeding these ratings will damage the module.
4. Does the 1790D-8BV8V require external DeviceNet power?
Yes. The module draws its logic power from the DeviceNet network. You must provide 24V DC DeviceNet power to the bus. Field power for outputs is separate.
5. How do I wire a load to a sinking output on the 1790D-8BV8V?
Connect the positive side of your load to +24V DC. Connect the negative side to the output terminal. The output switches the DC common. Current flows from +24V through the load into the output.
| Brand Name | Allen-Bradley |
| Model No. | 1790D-8BV8V |
| Product Type | I/O Module |
| hasMerchantReturnPolicy | Adjust according to reality |
| Shippingdetails | Adjust according to reality |
