IDEC FT1A Series User Manual

5: S PECIAL F UNCTIONS
5-38 S MART AXIS P RO /L ITE U SER ' S M ANUAL FT9Y-B1378
Input Filter
The input filter function is used to reject input noises. The catch input function described in the preceding section is used to read
short input pulses to special internal relays. To the contrary, the input filter rejects short input pulses when the SmartAXIS is used
with input signals containing noises.
Different input filter values can be selected for inputs I0 through I7 in four groups using the Function Area Settings. Selectable
input filter values to pass input signals are 0ms, and 3 through 15ms in 1ms increments. Default value is 3ms for all inputs I0
through I7. Inputs I10 and above on SmartAXIS are provided with a fixed filter of 3ms. The input filter rejects inputs shorter than
the selected input filter value minus 2ms.
Normal inputs require a pulse width of the filter value plus one scan time to receive input signals. When using the input filter
function, select Normal Input under Special Inputs on the Input Configuration dialog box in the Function Area Settings.
Since these settings relate to the user program, the user program must be downloaded to the SmartAXIS after changing any of
these settings.
Programming WindLDR
1. From the WindLDR menu bar, select Configuration > Input Configuration.
The Function Area Settings dialog box for Input Configuration appears.
2. Select an input filter value for each group of inputs.
Input Filter Values and Input Operation
Depending on the selected values, the input filter has three response areas to reject or pass input signals.
Example: Input Filter 8ms
Reject area:
Indefinite area:
Pass area:
Input signals do not pass the filter (selected filter value minus 2 ms).
Input signals may be rejected or passed.
Input signals pass the filter (selected filter value).
The columns displayed next to I0
indicate I0 to I7.
To reject input pulses of 6ms or less, select input filter value of
8ms. Then input pulses of 8ms plus one scan time are accepted
correctly at the END processing.
Indefinite
6ms 8ms + 1 scan
Rejected AcceptedInput

IDEC FT1A Series Specifications

General

Brand	IDEC
Model	FT1A Series
Category	Controller
Language	English