Sharing of on-site experience from seven years in ceremonies
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Today’s instruments are becoming increasingly intelligent, incorporating advanced technologies. Generally, when there is a malfunction with an on-site instrument, for reasons of safety and to avoid disruptions in production, it is replaced directly; as a result, the people who work with on-site instruments have become instrument replacement specialists – of course, this does not apply in cases where spare parts are unavailable! Today, a vortex flow meter (Rosemount) suddenly saw its reading drop from over 100 to just a few dozen kilograms per hour. The diagnosis indicated a lack of communication, and the voltage at the installation site was only 8V (the normal value is around 21V). I tried replacing the transmitter, but after much effort it turned out that the models were different and the configuration did not succeed (the minimum measurement range of the replacement transmitter was 580, while the applicable range for that flow meter was 340). With no other choice, I put the original transmitter back in use, and everything returned to normal! Damn, what I’m trying to say is that when using smart devices, like phones, if there are any problems, remember to turn them off first!
With a supply voltage of only 8V, it’s definitely impossible to establish HART communication. If you don’t investigate why there is only 8V at the power supply, simply replacing it with a vortex flow meter won’t solve this problem; not even a miracle worker could do that. :Lol; unless the power supply issue is resolved, it won’t last long even if it works fine now – the problem will recur.
Shut down, then restart! Just like with computers, it really happens sometimes, especially with smart meters – the software can have problems!
It’s not the voltage output of the card that’s problematic; rather, it’s the field transmitter that is faulty. As for which specific component is at fault, we’re waiting for experts to figure it out
If you don’t behave after drawing, you’ll have to deal with it yourself
After removing the module and reinstalling it, the voltage at the terminal changed; it seems unlikely that it’s a software issue – could it be a problem with the connection? But there was little vibration at the site
Sometimes it’s impossible to determine the cause, so the only option is to try turning off the power, the gas supply, and the signals. In most cases, a “freeze” is the most likely possibility.
Is it due to insufficient power supply that the controller cannot communicate? We have several Sercos differential pressure transmitters, and for some reason they won’t connect to the handheld controller; the supply voltage is below 24V. Could this be the cause? The rating on the label indicates a range of 15V–45V, but shouldn’t the supply voltage for the Lenze module be 24V? ! The voltage was 21.5V when the wires were disconnected on-site, and it dropped to 18.5V after the wires were connected; I have no idea what’s going on
It will work fine after disassembly; is there a possibility of poor contact originally?
Could it be that the insulation in the 24VDC power supply circuit has deteriorated, or is there a grounding issue?
It shouldn’t be; I’ve been using this watch for a few years now. I just reconnected the power cable and reinstalled the circuit module