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Entry type: FAQ, Entry ID: 43211193, Entry date: 06/15/2010

Why with module FM350-1 does the internal gate STS_GATE remain open in single count mode although the software gate SW_GATE closes?

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When using the counter module FM350-1, with the parameters given below, it might happen that although the software gate SW_GATE closes, the internal gate STS_GATE remains open and for this reason the counter group shows no function. The following parameterization leads to this behavior:

  • Single count mode
  • Counting range 0 to 32 bits
  • Gate function failure
  • Load value 0

As soon this parameterization sets the software gate SW_GATE to FALSE, counting is interrupted. If the software gate SW_GATE is set to TRUE again, the load value 0 is loaded. This makes the counter module FM350-1 recognize the counting range limit of 0 and counting stops, the STS_GATE remains FALSE and counter value remains 0.

You must change one of the following settings to remedy this behavior.

  • Select periodic counting instead of single count mode
  • Select a counting range of -31bits to +31bits instead of 0 to 32 bits
  • Select a load value not equal to 0

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