1756-CN2RXT

Technical specifications

Manufacturer

Allen-Bradley

Manufacturer part no.

1756-CN2RXT

Type

ControlNet communication module

Application

Communication module

Used with

ControlLogix 1756 chassis

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

30V (continuous), Basic Insulation Type, ControlNet A/B to Backplane, ControlNet A to ControlNet B, USB to, ControlNet A/B, and USB to Backplane, Type tested at 500V AC @ 60s

Logix communication connections

128

Module location

Chassis based, any slot

Number of nodes, max

99 nodes

Operating temperature

-25 to 70 °C

Power dissipation

6.6 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: 30g, 1756-CN2RXT/C, Nonoperating: 50g, 1756-CN2RXT/B

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

70 °C

Thermal dissipation

22.9 btu/h

Technical documents (1)

• Rockwell Automation technical data 1756-TD003

Key features

• Redundant ControlNet interface with two BNC ports
• Supports up to 99 nodes at 5000 kbps
• Operating temperature range of -25 to 70 °C
• Chassis based, any slot, one slot wide
• 128 Logix communication connections, 131 connections maximum

About the Allen-Bradley 1756-CN2RXT

The Allen-Bradley 1756-CN2RXT is a ControlLogix Communication Module, described by Rockwell as a ControlNet Redundant Interface Module (100 connections), Logix XT. Rockwell lists two ControlNet BNC ports, a transmission rate of 5000 kbps, a maximum of 99 nodes and 128 Logix communication connections. Rockwell also gives an operating temperature of -25 to 70 °C, a current draw of 1300mA @ 5.1V DC and an approximate weight of 0.293 kg. Rockwell lists its lifecycle status as Active Mature.

What is the 1756-CN2RXT used for?

The module is chassis based and fits any slot, providing a redundant ControlNet connection for a ControlLogix system. Rockwell lists 1786-RG6 quad shield RG6 coaxial cable as the ControlNet cable. It is used where a ControlLogix chassis needs to communicate over ControlNet.

Lifecycle and successor

Active.

Before you order

What to photograph or confirm so the right unit is quoted.

Check the catalog number 1756-CN2RXT on the module label, together with the series letter and firmware revision. Send us a photo of the label if you need help confirming the match.