I have a 5069-IB16 input card connected to a rack that is being monitored by a 5069-L320ERS2 safety controller. I have noticed that the input is showing a voltage reading of 16 volts when it should be reading 0V. I disconnected the wire from the input and tested it, finding that it is indeed registering 0V. I am concerned that this issue may be interfering with other inputs. Can anyone provide insight into what could be causing this discrepancy?
To prevent leakage through transistors, it is recommended to short out unused analog inputs. This is a common practice among devices with analog inputs. If you connect a device to the input and notice a voltage, it is important to troubleshoot. Unlike old VTVM meters and "wiggie's," DMM's do not drain, so they may show voltages that are not present during operation.
The safety controller in question is a GuardLogix, with the specific slot being slot 3. During my investigation, I tested an input from slot 2 which read around 12 volts, and then an input from slot 1 which showed 5 volts. While this information may not seem directly relevant, it is worth noting. The issue at hand was that despite wiring an input to send 24v to the input card, the input did not activate. This may be due to voltage interference causing the input to drop below the triggering threshold.
Safety inputs send pulses to the device to confirm current flow and ensure the device is still operational and no wires are broken. Similarly, safety outputs perform the same function but with a low voltage to avoid activating the device. These safeguards are intentionally designed to operate independently without impacting other inputs, the device itself, or its readings.
Although these are not traditional safety cards, they function as a safety controller featuring three regular digital inputs, two digital output cards, two analog input cards, and one analog output card, with safety input and output at the end. Interestingly, I discovered that turning off one of the MCPs caused the voltages to drop to just 5 volts. The correlation between these two events is unclear, but it is worth exploring further.
Hello, neighbor. It seems like there may be an issue with the SA power in your setup. Are your outputs alternating current (AC) and require a separate SA power feed from a FPD? Is the power supply negatively grounded? If you are reading from ground and your 24V- is not grounded, you may experience random voltage readings. When I tried a similar setup with just MOD and SA power connected for the first 8 modules, I observed less than 0.9 volts on the inputs. The voltage seems to decrease as more modules are added and as the system warms up after being powered on.
It sounds like you've done some thorough troubleshooting already! A constant 16V reading could indicate a few possible issues. First, check if there’s any grounding or noise interference in the wiring that could be inducing a voltage on the input. Additionally, confirm there aren’t any other nearby wires creating a phantom voltage effect. If everything looks good there, it may be worth considering whether there’s an internal fault with the input card itself, especially since it’s connected to a safety controller. It might be helpful to monitor the card's diagnostic indicators or even swap out the input card temporarily to see if the problem persists. Good luck!
It sounds like you're dealing with a classic case of noise or grounding issues that can happen in systems with high impedance inputs. Since the input card shows 16 volts despite the wire being disconnected, there could be phantom voltage present, potentially caused by nearby induced voltages or improper grounding which can interfere with the readings. I would recommend checking the wiring for any shorts or nearby interference sources, and also ensure that your grounding is solid to eliminate these stray voltages. Additionally, if you have access to an oscilloscope, it might be helpful to look at the signal waveform to get a clearer picture.
It sounds like you've already done some good troubleshooting by testing the wire directly. The 16V reading on the input card could potentially be caused by a couple of issues: stray voltages or phantom voltages can appear on unused inputs, especially if they're not grounded properly. You might want to check the wiring and ensure there are no nearby sources of interference or cross-talk affecting the signal. Also, it could be worth inspecting the input card configuration or performing a reset, since sometimes a software glitch can cause odd values to display. Lastly, don’t forget to verify that the grounding connections for the entire system are solid. Good luck!
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Answer: 1. Q: What could be causing a voltage discrepancy on the 5069-IB16 input card connected to the 5069-L320ERS2 safety controller? The voltage discrepancy could be caused by electrical interference, a faulty connection, or a malfunctioning component.
Answer: To troubleshoot the issue, you can try checking for loose connections, testing the wire independently, inspecting for any signal interference, or examining the input card for any defects.
Answer: Yes, a voltage discrepancy on one input could potentially interfere with other inputs on the same rack, so it's important to address and resolve the issue promptly.
Answer: You can ensure accuracy by double-checking connections, conducting thorough testing, eliminating sources of interference, and possibly replacing any faulty components.
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