Problems with Siemens PLCs
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For a PLC with 300 MB of memory, when a 512 K MMC card is inserted, all the SF lights on its AI cards turn red upon power-up; however, when no MMC card is inserted, those SF lights do not light up
Is it still the case that the content on the MMC card differs from the actual card model?
Expert, the status of the modules in my program shows normal, but the diagnostic interrupt option indicates that ‘the analog input range is below the minimum range’. What does that mean?
Check whether the AI’s jumpers, configuration, and wiring are correct.
I’m using 331-7KF02-0AA0 for my AI card; the 10.11 terminals in the middle are shorted together, all eight terminals operate in a two-wire configuration, and the mode block is set to D. So don’t the 2.3 terminals connect to the positive and negative terminals of the transmitter respectively?
Expert, I asked before about the display showing a value below the allowable range; it turns out that one of the channels wasn’t connected (the transmitter). Is it because of this that the SF light on the AI card comes on?
In a 2-wire system, a 24V power supply needs to be connected to the channel; without this connection, the SF light on the module will not light up either.
From what I’ve seen, if the SF light of the 7KF02 is on, it’s very likely that there is an issue with the 24VDC power supply for the card.