IDEC FC6A Analog Input and Output Configuration in WindLDR

Quick Answer

The FC6A supports 4-20mA, 0-10VDC, 0-5VDC, thermocouple, and RTD analog inputs depending on the CPU variant and expansion modules. Configure input types in WindLDR Function Area Settings, use the SCL instruction for raw-to-engineering-unit scaling, and write analog output values to designated R registers.

FC6A Analog I/O Options

• Onboard analog inputs — 2-4 channels depending on CPU variant (12-bit, 0-4000 count range)
• Expansion analog modules — Additional channels with 4-20mA, 0-10V, thermocouple (J, K, T, E, R, S, B), and RTD (Pt100, Pt1000) inputs
• Analog outputs — 4-20mA or 0-10V output channels

Configuring Input Type

In WindLDR, navigate to Function Area Settings → Analog I/O. Select the input type for each channel (voltage, current, thermocouple, or RTD). The raw count range depends on the input type and module — typically 0-4000 for standard analog or 0-32000 for high-resolution modules.

Scaling with the SCL Instruction

The SCL (Scale) instruction performs linear interpolation between raw input range and engineering unit range:

• Source: Raw analog input register
• Input range: 0-4000 (for 4-20mA)
• Output range: 0.0-500.0 (e.g., PSI)
• Destination: R register for scaled value

For field device scaling comparisons, see how Bristol FB300 handles analog scaling and Geo SCADA configures analog points.

Analog Output Configuration

Write a value (0-4000) to the designated analog output register in R memory. The FC6A converts this to the corresponding 4-20mA or 0-10V signal on the output terminal.

Input Filtering

WindLDR provides analog input averaging/filtering settings to reduce noise. Configure the number of samples averaged (1-64) in the analog channel setup to smooth noisy signals from vibrating environments or long cable runs.

Example: Reading a Pressure Transmitter

A 4-20mA pressure transmitter (0-300 PSI) connected to analog input channel 1. Raw count range: 0-4000 (where 0=4mA=0PSI, 4000=20mA=300PSI). SCL instruction scales to engineering units and stores the result in R100 for use in alarm comparison and HMI display.