- Bad communication ports
- Broken selector/key switches
- Dead batteries/Bad Battery connections
- Solid or Blinking RED OK Status Light
- Solid or Blinking RED RUN Status Light
- Solid or Blinking RED Fault Status Light
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Allen Bradley 1791 Block I/O Repair
We offer extensive repairs for your 1791 Block I/O. We keep many spare parts in stock so that we can repair your 1791 Block I/O as efficiently and effectively as possible. Our standard repair lead time is 2-4 weeks. However, we can often repair your unit much faster if necessary. We can repair most issues with your 1791 Block I/O and if for some reason we cannot repair your unit we will do our best to offer a refurbished unit at the repair cost, so that you can get a working unit back as soon as possible!
- 2 Year DO Supply Warranty
- Fast repairs at low costs
- No surprises or up-charges for difficult repairs
- Standard lead time of 2-4 weeks
- Extensive quality control and testing
Get a repair quote
Not an Authorized Distributor: DO Supply is not an authorized distributor for listed manufacturers or tradenames and therefore the manufacturer's
warranty does not apply. All of our products come with DO Supply's 2-year warranty.
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Hardware issues & error codes we repair
We repair all of the following hardware issues and error codes with your 1791 Block I/O parts.
- Bad analog inputs or ouptus
- Bad digital input or outputs
- Bad relays (stuck on/off)
- Incorrect voltages on inputs or outputs
- Incorrect current on inputs or outputs
- DF1, DH-485, DH+, Profibus, Remote I/ (RIO) failures and more!
- Intermittent communication
- Solid RED/Blinkging RED communication lights
- Devicenet, Ethernet, ControlNet, RS232 ports.
- Missing CJC Jumpers
- Incorrect readings
- Failed inputs
- Dead power supplies
- Incorrect voltage
- Broken Plastic
- Poor Connections
- Bad Slots
Browse 1791 Block I/O Repairs
Browse our catalog of repairable 1791 Block I/O parts to get a quote.
1791-IOBW
24V dc BLOCK I/O Allen-Bradley AB with 32 Sinking Inputs per Block and 32 Sourcing Outputs per Block. Surplus and Used in Stock!
In Stock Ships Today
1791-IOBX
24V dc BLOCK I/O Allen-Bradley AB with 64 Sinking Inputs per Block and 64 Sourcing Outputs per Block. Surplus and Used in Stock!
In Stock Ships Today
1791-IOVW
24V dc BLOCK I/O Allen-Bradley AB with 32 Sourcing Inputs per Block and 32 Sinking Outputs per Block. Surplus and Used in Stock!
In Stock Ships Today
1791-IOVX
24V dc BLOCK I/O Allen-Bradley AB with 64 Sourcing Inputs per Block and 64 Sinking Outputs per Block. Surplus and Used in Stock!
In Stock Ships Today
1791-N4C2
The 1791-N4C2 module is an Allen-Bradley Block I/O module. The Block I/O module features 6 analog I/O points (4 analog inputs and 2 current outputs).
In Stock Ships Today
1791-N4V2
This module features four analog current/voltage inputs and four analog voltage outputs. It operates on an AC supply voltage of 120V. The output voltage can vary between -10 to 10V. For ease of instal
In Stock Ships Today
1791-NDC
The Allen-Bradley 1791-NDC Analog Block I/O Module has a 11.52 W max. Power Dissipation and a 5 Hz Input Bandwidth.
Available
1791-NDV
This module features a 14-bit resolution for accurate signal conversion and an input bandwidth of 5 Hertz. Its common mode rejection ratio is noteworthy at -75 decibels, allowing reliable performance
In Stock Ships Today
1791-OA16
The Allen-Bradley/Rockwell Automation 1791-OA16 AC Block I/O module that has been developed by Allen-Bradley/Rockwell Automation to provide a multi-output device that can be paired with different kind
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1791-OB16
Designed for flexibility, the 1791-OB16 operates at an output voltage range of 10 to 30V DC and accepts an external DC power supply ranging from 19.2 to 30V DC. It can handle a maximum output current
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About 1791 Block I/O
The 1791 block I/O module series by Allen-Bradley is a series of compact, stand-alone, and remote I/O devices with built-in power supplies, programmable controller interfaces, input/output points, and signal conditioning circuitry for complete system control. These modules are compatible with the Allen-Bradley PLC (2, 3, and 5) controllers and the SLC-500 modular controllers, and they are connected either directly to the controllers in the PLC-3 and PLC-5 programmable controller family or they are connected by using compatible scanner modules. The 1791 block I/O modules have DC power requirements with an operating voltage range between 10 and 30 Volts DC, and they require 200 milliamps of current and a 5.5 Amps (for 10 milliseconds) inrush current to power each block. This series features modules with sinking and sourcing inputs and outputs ranging from 8 to 64 connections, and they have removable remote I/O links, input/output connectors, and terminals for external 24 Volts DC power supply that help reduce wiring costs.
The 1791 block I/O modules have dual DIP switches for setting the I/O configurations and addressing rack numbers. These switches also let the users select and adjust the transmission rates, initiate last racks and I/O groups, and select the last state and DH–485 terminator. A DH-485 port is provided in all modules for connecting to SLC controllers, and this network (DH-485) offers a maximum network communication distance of 4,000 feet. A bi-color LED indicator is also provided on every module for providing power, active, communication, and fuse blown statuses. Depending on the application requirements, multiple I/O blocks can be wired in series via the removable connectors, and a termination resistor must be wired on both ends of the wiring series. The 1791 block I/O modules can provide a maximum network distance range of 2000 to 10,000 cable-feet, and an adjustable baud rate from 57.6 Kilo-baud to 230.4 Kilo-baud.