Variable Signaling Function - Siemens Sinamics S120 Function Manual

3.18

Variable signaling function

Using the "Variable signaling" function, BICO interconnections and parameters, which have
the attribute traceable, can be monitored.
Note
Attribute "traceable"
A parameter, whose value can be acquired using the trace function of STARTER or SCOUT,
is allocated the "traceable" attribute. These parameters can be called in STARTER or
SCOUT under the device trace function. The attribute itself is not visible.
Enter the desired data source into parameter p3291 of the expert list of drive object. In
parameter p3295 define a threshold value for the data source. The hysteresis of the
threshold value can be set with p3296. If the threshold value is violated, then an output
signal is generated from r3294.
A pickup delay can be set with p3297 and a dropout delay with p3298 for the output signal
r3294.
The setting of a hysteresis results in a tolerance band around the threshold value. If the
upper band limit is exceeded, the output signal r3294 is set to "1", if it drops below the lower
band limit the output signal is set to "0"
You set the sampling time of the variable signaling function in p3299.
After completing the configuration, activate the variable signaling function with p3290.0 = 1.
Note
The variable signaling function works with an accuracy of 8 ms (also to be taken into account
for pickup and dropout delay).
Example 1:
Heating should be switched on depending on the temperature. For this the analog signal of
an external sensor is connected with the variable signaling function. A temperature threshold
and a hysteresis is defined to prevent the heating from switching on and off constantly.
Example 2:
The pressure as process variable is to be monitored, whereby a temporary overpressure is
tolerated. For this the output signal of an external sensor is connected with the variable
signaling function. The pressure thresholds and a pull-in delay are set as tolerance time.
When the output signal of the variable signaling function is set, bit 5 in message word
MELDW is set during cyclic communication. The message word MELDW is a component of
the telegrams 102, 103, 105, 106, 110, 111, 116, 118, 126.
Drive functions
Function Manual, (FH1), 01/2012, 6SL3097-4AB00-0BP2
Servo control
3.18 Variable signaling function
127