Product overview
EL125x, EL2258
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Version: 2.5
Fig. 16: Output of output channel information, oversampling
• This procedure enables a significantly finer time resolution to be achieved for the actuator control, even
below the actual cycle time.
The digital output terminal EL2262 can achieve a time resolution of 1 µs with 1000-fold oversampling.
•
Timestamp
With the timestamp principle the controller calculates an exact time at which the output is to switch to a
new state 0/1. After this switching order has been transferred, the terminal waits until this time is
reached and then switches automatically, independent of the bus cycle. Here too the distributed clocks
function is decisive. It synchronizes the local clock that runs in the output terminal.
Fig. 17: Output of output channel information, with timestamp
• At (A) the controller transfers a switching order consisting of output state and switching time to the
output channel; the order is executed at (B) independently of the cycle. The controller can then send a
new switching order (C). The ‘infinitely’ fine time resolution of 1 ns applies here as well.
In general the digital output terminal EL2252 with oversampling requires two cycles for activating a
switching order.
Multi-timestamp
The multi-timestamp capability opens up new application options for digital inputs and outputs:
Inputs EL1258, EL1259
• 8 multi-timestamp channels on an overall width of 12 mm
• All channels operate completely independently of one another
• Each channel is capable of sampling not only one, but up to 32 signal edges (“events”) per cycle
• Each channel has its own buffer. Events are held in the buffer, if more signal edge changes arrive at
the input during a cycle than are retrieved via the process data. The buffer can be sent continuously to
the controller via the cyclic process data. A handshake mode is also possible – thus no signals to the
controller are lost in the event of communication errors.
• The process data size can be configured individually for each channel, i.e. how many timestamped
events per cycle are to be retrieved from the channel by the PLC
