I am troubleshooting a fault on a machine with a B&R X20CP1484 CPU and an ACOPOS 1090 servo drive, and I would appreciate your insights.
System Configuration:
PLC: X20CP1484 (Node 1, IP: 172.16.0.5)
Drive: ACOPOS 1090
Communication Module: AC114 (POWERLINK, set to Node 2: x16=0, x1=2)
I/O Encoder Module: 8AC130.60-1
Symptoms:
The ACOPOS drive Error LED is flashing 3 red blinks (According to the manual: Error booting the AC114-ARM).
The HMI displays PVI Error 4813 (Identification error reading variables), likely because the motion tasks are not initializing.
Troubleshooting steps taken so far:
Network & Node IDs: Verified the node switches. The AC114 is properly addressed as Node 2. The L/D1 LED on the AC114 flashes green, confirming physical Ethernet link/data activity with the PLC. I can also successfully ping the PLC IP from my PC.
8AC130 Module Power Issue: The 24V Green Status LED on the 8AC130 module is completely OFF (which means internal sensing is below 18VDC).
Voltage Test: I measured exactly 24 VDC with a multimeter directly on terminal pins 11 (+24V) and 12 (COM). The external power supply is healthy.
Isolation Test: I disconnected all encoder and digital I/O wires from the 8AC130 terminal block, leaving only the 24V power connected. The 24V LED remains completely OFF.
Since the AC114 shows an internal ARM boot error and the 8AC130 behaves as if it has no power (despite having 24V on its terminal), I suspect an internal hardware fault.
Could a damaged internal SMD fuse/PTC on the 8AC130 module prevent it from booting, or is it more likely that the ACOPOS internal backplane power supply has failed, affecting both option slots?
Hi Jose, welcome to the B&R Community! Before we provide some troubleshooting recommendations, can you please describe the context in which the issue was first seen? I assume this machine has been running fine for some time. Did something change (e.g. new software version installed or did something happen (e.g. power outage on-site, etc.) before the issue was observed?
Depending on what software versions are being used, PVI error 4813 could be a known issue related to a new module format that was added in AR 3.00. So, if there was recently a software update and then this issue was observed, I could imagine that this is the issue. The resolution for this is to upgrade the PVI version on the HMI to a version beetween V3.00.02.3019 and V4.2.6.84 (V3.0 is the earliest version that can communicate with AR 3+, and V4.2 is the last official version supported on Windows XP). These versions can be downloaded from the website at this link: PVI Development Setup | B&R Industrial Automation
If there has not been a software update on the X20CP1484 or on the HMI, then there is more likely a hardware issue. Have you already tried re-seating both interface cards? Do you have any spare hardware (e.g. ACOPOS 1090, AC114, AC130) on hand that you could try swapping in? Make sure also that the terminal block is inserted into the AC130 the right. It should only be able to go in one direction, but we have seen a case before where it was flipped somehow.
​Thank you for the welcome and the recommendations! Here is the exact context of how the issue started:
​There have been no software updates at all, and absolutely nothing was modified on the CPU. The machine had been running fine for a long time, but it recently started triggering encoder faults. To fix that, we initially replaced both the encoder and its cable, but since the issue persisted, we ultimately decided to swap out the ACOPOS drive.
​The current LED errors started right after we replaced the ACOPOS 1090. Here are the details of what we’ve done:
​Modules Reused: We kept and transferred the exact same communication module (AC114) and encoder card (8AC130) to the replacement drive.
​Hardware Swaps: We have already tried 3 different identical ACOPOS 1090 drives, and they all exhibit the exact same behavior (3 red blinks on the AC114 and the 24V LED off on the 8AC130).
​Original Hardware: We even reinstalled the original ACOPOS drive back into the cabinet, and now it is doing the exact same thing too.
​Node Addresses: We double-checked the hardware node switches (x1 and x16 dials) on the interface cards, and they are properly configured and match the original settings.
​Since swapping the main ACOPOS housing didn’t change the behavior across 3 different units, we are now suspecting a hardware failure specifically on the plug-in cards themselves (likely the AC114 or 8AC130). We are currently waiting for spare interface cards to arrive so we can swap them out next.
​Any additional insights based on this behavior would be greatly appreciated!
​Quick update: the new AC114 card arrived. We just replaced it, and it worked!
​It appears the original card was somehow damaged during the initial ACOPOS swap, even though it looked physically fine and we still don’t know the exact cause.