Alpha-X analog I/O modules are designed to read analog signals from external sensors and devices (analog inputs), and to control external equipment using physical current or voltage signals (analog outputs).
Ideal for PLC I/O expansion, these modules communicate via RS-485 using Modbus RTU. This ensures native compatibility with ELHART PLCs and any third-party, Modbus RTU-compliant controllers.
Easily configure your devices with the free ELHART Configurator software.
Alpha-X AI 8 converts standard analog input signals into digital form for reading via the RS-485 interface.
The expansion module features 8 inputs. Each input is configured independently and can measure 0…10 V or 0(4)…20 mA with 0.1% accuracy. The module has 1500 V galvanic isolation between power, the RS-485 communication interface, and analog inputs.
Alpha-X AI 6T is a six-channel digital converter for thermocouple (TC) and resistance temperature detector (RTD) signals. It supports TCs type J, K, L, B, S and RTDs Pt100, Pt1000, with 0.25% measurement accuracy. Temperature readings are available as an integer or as a floating-point number. Measuring channels are galvanically isolated from power and the interface.
Alpha-X AO 4 is an analog output module for standard current or voltage signals. Each output can operate in current or voltage generation mode. The module has four independent output channels with common galvanic isolation. Analog outputs are active and do not require an external power supply.
| Modifications | AI 8 | AI 6T | AO 4 |
|---|---|---|---|
| Maximum power consumption, W | 1.5 | 1.5 | 5.0 |
| Number and type of input channels | 8 analog |
6 temperature |
- |
| Number of output channels | - | - | 4 analog 0(4)…20 mA / 0…10 V |
| Analog input parameters | ||
|---|---|---|
| Input type | analog | temperature |
| Supported signals | 0(4)…20 mA / 0…10 V (range can be adjusted) |
RTDs: Pt100, 100P, Pt1000 TCs: J, K, L, B, S |
| Basic error limit | 0.1% FS | 0.25% FS |
| Minimum polling time per input | 250 ms 70 ms (with notch filter disabled) |
0.32 s |
| Input resistance, current measurement in mA | 22 Ω | - |
| Input resistance, voltage measurement in V | 100 kΩ | - |
| Input resistance, voltage measurement in mV | - | > 1 MΩ |
| Cold junction temperature accuracy | - | ±2 °С |
| Lead resistance compensation for RTDs | - | 20 Ω |
| Analog output parameters | ||
|---|---|---|
| Supported signals | 0…20 mA (0 → 100%) 4…20 mA (0 → 100%) 0…10 V (0 → 100%) 0…20 mA (100 → 0%) 4…20 mA (100 → 0%) 0…10 V (100 → 0%) |
|
| Output type | Active Output | |
| Basic error limit | 0.1% FS | |
| Nonlinearity | 0.05% | |
| Ambient temperature coefficient error | 0.05% / 10 °С | |
| Max. load resistance for current signal | 600…800 Ω (at 22…26 VDC supply) |
|
| Min. load resistance for voltage signal | 5 kΩ | |
| Parameter | Value |
|---|---|
| General | |
| Nominal supply voltage | 24 VDC (range 22…26 VDC) |
| Communication Interface | RS-485 |
| Supported protocols | Modbus RTU (Slave) |
| Interface baud rates | 2400, 4800, 9600, 14400, 19200, 28800, 38400, 57600, 76800, 115200, 128000, 256000 bit/s |
| Galvanic isolation of the interface | 1500 V |
| Ingress Protection | IP20 |
| Service life | 10 years |
| Operating conditions | |
| Operating temperature | -20…+50 °C |
| Relative humidity | 10...80% (without condensation) |
| Terminal | Description |
|---|---|
| B1 | Supply voltage, U (+) |
| B2 | Supply voltage, U (-) |
| B3 | Protective ground, GND |
| B4 | RS-485 interface, A (+) |
| B5 | RS-485 interface, B (-) |
