IDEC SmartAXIS Touch FT1A Series, User Manual

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SmartAXIS Touch User's Manual
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4 Special Functions
3
Pr
oject
4.12 Analog Input
This section describes how to configure analog input signals such as those from pressure sensors.
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Feature Description
The Touch is equipped with two analog inputs.
The FT1A-*12RA-* accepts analog input of 0 to 10V DC by converting it to 0 to 1000 digital values.
The FT1A-*14KA-* and the FT1A-*14SA-* accepts analog input of 0 to 10V DC or 4 to 20 mA by converting it to 0 to
1000 digital values. The converted analog input values are stored in special data registers. Inputs that are not
specified as analog inputs are digital inputs. For the on or off judgment threshold value when digital input is specified,
refer to Chapter 29 “SmartAXIS Specifications” on page 29-1.
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Applicable Models
The type analog input that can be used varies based on the model.
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Storage Locations for the Analog Input Value and Analog Input Status
The Touch has two embedded analog inputs. The digitally converted analog input values are stored in special data
registers (D8040 and D8041: read-only) as values between 0 and 1,000. The analog input status is also stored in
special data registers (D8042, D8043, and D8077: read-only). These values are updated with each scan.
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Analog Input Status (D8077)
If the analog input signal exceeds 11 V or 21 mA, the corresponding bit of D8077 turns on to indicate overflow. For
details, refer to Chapter 27 “2.2 Control Device Addresses” on page 27-12.
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Analog Input Status (D8042, D8043)
Details on the analog input status (D8042, D8043) are as follows.
Analog input
FT1A-*14KA-*
FT1A-*14SA-*
FT1A-*12RA-*
0 to 10 V YES YES
4 to 20 mA YES NO
Analog input terminal AI0 AI1
Special data register that stores the analog input value D8040 D8041
Special data registers that store the analog input status
D8077
D8042 D8077
D8043
Status Description Analog input value
0 Operating normally Current analog input value
1
Converting data (occurs only once during the initial
conversion when the power is turned on)
Undefined value
2 Initializing 0
3 Parameter setting error
Correct value immediately before the error
occurred
4 Reserved ―
5
Wiring fault (out of maximum range)
Analog input signals exceed 11 V, or 21 mA
Maximum
6
Wiring fault (out of minimum range, open current loop)
Analog input signals fall below 2 mA
Minimum
7 to 65535 Reserved ―