
Image is for illustrative purposes only. Please refer to product description.
- Manufacturer
- Allen-Bradley
- Manufacturer part number
- 1756-CN2R
- Product family
- ControlLogix Communication Modules (1756)
- Technical datasheet
- Data sheet
Specifications
| Attribute | Value |
|---|---|
| Type | ControlNet interface module |
| Manufacturer lifecycle | Active |
| Communication | ControlNet |
| Connection Cables | 1 m Tap |
| Number Of Channels | 2 |
| Conducted RF immunity | 10V rms with 1 kHz sine-wave 80% AM from 150 kHz...80 MHz |
| Connections supported, max | 131 maximum |
| ControlNet cable | 1786-RG6 quad shield RG6 coaxial cable |
| ControlNet port | 2 ControlNet BNC |
| Current draw | 1300mA @ 5.1V DC, 3mA @ 24V DC |
| EFT/B immunity | ±3kV @ 5kHz on ControlNet ports |
| Emissions | CISPR 11: Class A |
| Enclosure type rating | None (open-style) |
| ESD immunity | 6 kV contact discharges, 8 kV air discharges |
| Isolation voltage | Standard: 30V (continuous), basic insulation type, ControlNet network to, backplane, Redundant: 30V (continuous), basic insulation type, ControlNet A/B to, backplane, and ControlNet A to ControlNet B, USB to backplane and USB to ControlNet, No isolation b |
Show all 34 specificationsShow fewer specifications
| Logix communication connections | 128 |
|---|---|
| Module location | Chassis based, any slot |
| Number of nodes, max | 99 nodes |
| Operating temperature | 0 to 60 °C |
| Power dissipation | 6.7 W |
| Radiated RF immunity | 10 V/m with 1 kHz sine-wave 80% AM from 80...2000 MHz, 10 V/m with 200 Hz 50% Pulse 100% AM @ 900 MHz, 10 V/m with 200 Hz 50% Pulse 100% AM @ 1890 MHz, 3 V/m with 1 kHz sine-wave 80% AM from 2000...2700 MHz |
| Redundancy | Yes |
| Relative humidity | 5...95% noncondensing |
| Shock | Operating: 30 G, Nonoperating: 30 G |
| Slot width | 1 |
| Storage temperature | -40 to 85 °C |
| Supporting protocol for other bus systems | Yes |
| Surge transient immunity | ±2 kV line-earth (CM) on ControlNet ports |
| Surrounding air temperature, max | 60 °C |
| Thermal dissipation | 22.9 btu/h |
| Transmission rate | 5000 kbps |
| Vibration | 2 G @ 10...500 Hz |
| Weight, approx | 0.293 kg |
| Wiring category | 1 - on ControlNet ports, 3 - on USB ports |
Description
The Allen-Bradley 1756-CN2R is listed by Rockwell Automation as a ControlLogix Communication Module, described as a ControlNet Redundant Interface Module (100 connections). Rockwell gives its lifecycle status as Active Mature. Rockwell's product data lists 2 ControlNet BNC ports, a transmission rate of 5000 kbps, a maximum of 99 nodes and 128 Logix communication connections. It draws 1300mA at 5.1V DC, dissipates 6.7 W and has an operating temperature of 0 to 60 °C.
Application: Communication module
Used with: ControlLogix 1756 chassis
What is the 1756-CN2R used for?
The module provides ControlNet communication for a ControlLogix chassis and can be fitted in any slot. Rockwell lists redundancy support and names 1786-RG6 quad shield RG6 coaxial cable as the ControlNet cable. It is used where a ControlLogix controller must exchange data with other devices over a ControlNet network.
Key features
- Redundant ControlNet interface with two BNC ports
- Chassis based module, any slot, one slot wide
- Transmission rate of 5000 kbps
- Supports up to 99 nodes on the network
- Operating temperature range of 0 to 60 °C
Documents and Resources
Associated Products
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|---|---|---|---|---|---|
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![]() | 1756-CNBAllen-Bradley | ControlLogix ControlNet communication module, 1 BNC | In stock | View | |
![]() | 1756-CNBRAllen-Bradley | ControlLogix ControlNet communication module, redundant | In stock | View | |
![]() | 1756-DNBAllen-Bradley | ControlLogix DeviceNet bridge and scanner module | In stock | View | |
![]() | 1756-EN2FAllen-Bradley | ControlLogix EtherNet/IP module, 100 Mbps multimode fiber | In stock | View | |
![]() | 1756-EN2TAllen-Bradley | ControlLogix EtherNet/IP communication module, 10/100 Mbps | In stock | View | |
![]() | 1756-EN2TRAllen-Bradley | ControlLogix EtherNet/IP module, dual port 10/100 Mbps | In stock | View | |
![]() | 1756-EN2TXTAllen-Bradley | ControlLogix EtherNet/IP module, extended temperature | In stock | View | |
![]() | 1756-EN3TRAllen-Bradley | ControlLogix EtherNet/IP module, dual port copper | In stock | View | |
![]() | 1756-ENBTAllen-Bradley | ControlLogix EtherNet/IP communication module, 10/100 Mbps | In stock | View | |
![]() | 1756-CN2RKAllen-Bradley | ControlLogix Redundant ControlNet Module, Conformal Coated | In stock | View |
Product Questions
Is the 1756-CN2R discontinued?
No. Its manufacturer lifecycle status is Active.
Can another Allen-Bradley ControlLogix Communication Modules part replace it?
Potential replacements must be checked against the required ratings, dimensions and connections. Sharing a family name does not establish interchangeability.
Do you ship worldwide?
Yes. TimControls ships worldwide. Parts usually ship within 3 to 7 working days of order confirmation, and the exact lead time and shipping options are stated on your quote. Include your delivery country and postal code when you ask for a quote.
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