Siemens SIMATIC S7-300 FM 350-1, Руководство пользователя

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Product Overview
1.1 Properties
FM 350-1 Counter module
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Manual, 05/2011, A5E03648639-01
1.1 Properties
Properties
The FM 350-1 function module is a high-speed counter module for use in the S7-300
programmable controller. There is one counter on the module that can operate alternatively
in the following ranges:
●
0 to +32 bit:
0 to 4 294 967 295 (0 to 2
32
– 1)
● -31 to +31 Bit:
–2 147 483 648 to + 2 147 483 647 (–2
31
to 2
31
– 1)
The maximum input frequency of the counter signals is up to 500 kHz depending on the
encoder signal.
The FM 350-1 can be used for the following tasks:
●
Continuous counting
● Single counting
● Periodic counting
● Frequency measurement
● Speed measurement
● Period measurement
You can start and stop each mode either via the user program (software gate) or via external
signals (hardware gate).
Comparison Values
You can store two comparison values on the module assigned to the two relevant outputs on
the module. If the counter status reaches one of the two comparison values, the relevant
output can be set to initiate control actions direct in the process.
Load value
You can specify a value on the FM 350-1 from which it should begin counting. This value is
the load value. Any value within the count limits can be set for the load value.
Hardware Interrupts
The FM 350-1 can trigger a hardware interrupt in the CPU if the comparison values are
reached, or in the case of overflow, underflow and/or a zero crossing of the counter.