Allen Bradley Quest AN-X2-AB-DHRIO Remote I/O Adapter Integration and Troubleshooting

Allen Bradley Quest AN-X2-AB-DHRIO Remote I/O Adapter Integration and Troubleshooting

How to smoothly integrate old RIO racks, discrete I/O, and block transfer data into the ControlLogix platform is a problem that many renovation projects cannot avoid on sites where existing Allen Bradley Remote I/O systems are still running in large quantities. The Quest AN-X2-AB-DHRIO remote I/O adapter is designed as an Ethernet gateway for such scenarios: it connects to the EtherNet/IP network of ControlLogix on one end and the Remote I/O network on the other end, and maps RIO data to the scheduling connection data area of ControlLogix through configuration software. For engineers, what truly determines the success or failure of a project is often not whether it can be connected, but whether the rack mode, terminal resistance, mapping relationship, connection type, and LED diagnosis are handled correctly.

Module positioning and two rack modes

AN-X2-AB-DHRIO, as a Remote I/O adapter, has one RIO channel and can simulate one or more racks. It supports three baud rates of 57.6, 115.2, and 230.4 kbaud, with rack numbers ranging from octal 00 to 76, and supports some rack combinations. It can monitor discrete I/O and block transfer read/write on the same RIO network, as well as update I/O data through ControlLogix scheduling connections. The module communicates with ControlLogix through Ethernet, and RIO data is mapped from the configuration program to scheduling input and output data.

Understanding the two modes of "Active" and "Monitored" is the first step in configuration. The Active rack is simulated by AN-X2-AB-DHRIO, and ControlLogix writes RIO input and block transfer read data to the adapter, and reads RIO output and block transfer write data from the adapter. Monitored rack is a real rack that exists on the network, and ControlLogix only reads its RIO input, output, and block transfer read/write data. All data is mapped to the input area of ControlLogix. If a rack number contains both Active and Monitored partial racks, monitoring data is mapped to CLX input, Active input is mapped to CLX output, and the mapping is effective for the entire rack number. Partial racks cannot be mapped separately.

Hardware, power supply, and microSD maintenance

The front panel of the module provides 10/100 Ethernet ports, 12-24 VDC power terminals, three pin Phoenix RIO network terminals, as well as 100, Link/ACT, SYS, NET and other LEDs. The power terminals from left to right represent the chassis ground, negative voltage, and positive voltage, and the chassis ground should be reliably connected. The power consumption of the module is about 200 mA@12 VDC or 100 mA@24  VDC， The maximum power consumption is about 2.4 W, the operating temperature is 0-50 ° C, and the humidity is 5% -95% non condensing. It is recommended to install ferrite magnetic rings on Ethernet and power cables for CE installation, and corresponding magnetic rings should also be installed on RIO/DH+cables.

The important difference between AN-X2 and the original AN-X is the use of microSD cards to store firmware and configuration data. The card format must be FAT-16 or FAT-32, with no limitations on capacity and speed, but the module must be inserted during operation, and it is strictly prohibited to unplug the card while it is still powered on. If the module cannot be accessed from Ethernet due to IP settings, you can remove the card after power failure, modify the IP, Netmask, DefGtwy, Hostname, and Firmware fields in the config. txt file using a text editor, and then plug them back in with the pins facing up. When inserting the card, it should be pushed straight to avoid the card falling into the shell. The module hardware also includes watchdog and Jabber inhibitor protection: firmware that is not "fed to the dog" on time will enter a safe and fatal fault; If the transmitter conducts for more than 150% of the maximum frame time, it will be forcibly shut down and enter a safe state.

RIO wiring, terminal resistance, and cable length

RIO terminals are defined as Line 1, Shield, and Line 2, with Line 1 being the closest to the power terminal. When wiring, it is necessary to ensure that Line 1 of AN-X2 corresponds to Line 1 of PLC, and the shielding layer should be treated according to the on-site specifications. The RIO network must have one and only one terminating resistor installed at each physical end. If the network is running at 230.4 kbps, or at 57.6/115.2 kbps and there are no devices such as 1771-AS, 1771-ASB A/B series, 1771-DCM, 1771-AF, 1771-AF1 in the network, use an 82 Ω resistor; If the network includes the aforementioned devices or does not require support for more than 16 physical devices at 57.6/115.2 kbps, use a 150 Ω resistor. The maximum number of physical devices in the network is 32. The cable length is limited by the baud rate: 57.6 kbaud is approximately 10000 feet, 115.2 kbaud is approximately 5000 feet, and 230.4 kbaud is approximately 2500 feet. When connecting Ethernet directly to a computer, use a crossover cable, and when passing through a switch or router, use a standard straight through cable.