IV25101A_e.DOC / Feb-08
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1msec
2msec
3msec
SSI-Telegram
Calculations
Auswertung
TM1
0msec
TM2
SSI-Telegram
SSI Wait Time = 3 msec
Analogue
Update
Analogue
Update
•
The shortest possible time for equidistant updating is 1.3 msec, due to
internal processing times (SSI Wait Time set to 0.001)
•
The time marks TM1 and TM2 shown in above diagram can be displayed with
the Monitor function of the PC operator software. It is easy to understand
that the sum of both times must be equal to the Wait Time setting; other-
wise you must increase the Baud rate or choose a longer update cycle.
(The serial access codes are :3 for TM1 and :5 for TM2)
•
In critical cases you can reduce the internal processing times of the unit, by
omitting the conversion of serial RS232 encoder data. For this, just set
parameter “/Operand” to 00000
SSI Offset:
Defines the electrical zero position of the encoder with respect to the mechanical zero position.
When the Round-Loop function is not active (Round-Loop = 0), the SSI Offset is subtracted from
the SSI position reading, which can also cause negative results. When the Round-Loop is
active, SSI Offset displaces the mechanical zero position, but always with only positive results.
SSI Set Value:
Applying a remote Set signal to the Set input (terminal 10) results in a temporary substitution of
the SSI position value by the SSI Set Value entered here. This function allows easy testing and
simulation of fixed analogue output values while commissioning.
