====== MPAINO F PT100 input module ======

The F option module reads two-wire or three-wire PT100Ω temperature sensors. Each module has four channels and is assembled into the ordered MPAINO product before shipment. X analog input and F PT100 input modules can total no more than five modules (20 channels). Check the configuration supplied with your product before wiring or choosing channel numbers.

===== Specifications =====

{{:en-us_products:mpaino-option-f-front.png?220|F PT100 input module front}}

^ Item ^ Description ^
| Option codes | F, F2, F3, F4, F5 |
| Inputs per module | Four PT100Ω channels |
| Sensor wiring | Two-wire or three-wire |
| Measurement range | −200 to +800°C |
| Display resolution | 0.1°C |
| Accuracy | ±0.1% or less at 25°C ±5°C ambient |
| Converter | ADS1118 |
| Maximum configuration | Five F modules; X and F together no more than five modules |

Resolution is the displayed step. The stated accuracy has its own test conditions and does not remove sensor or lead-wire error.


{{ :en-us_products:mpaino-f-channels.svg?1000 |Four channels per F module and consecutive program channel numbers }}

===== Ordered configuration and channel numbers =====

^ Option ^ F modules ^ PT100 inputs ^ ''pt100Read(ch)'' with F modules only ^
| F | 1 | 4 | 0–3 |
| F2 | 2 | 8 | 0–7 |
| F3 | 3 | 12 | 0–11 |
| F4 | 4 | 16 | 0–15 |
| F5 | 5 | 20 | 0–19 |

Each module labels its physical terminals CH0–CH3, while program channels continue across modules. With F2 alone, CH1 on the second F module is ''pt100Read(5)''. For a product containing both X and F modules, confirm the shipped channel allocation instead of applying the F-only table. For example, X3F2 contains five modules and is allowed; X3F3 would contain six and is not.

===== Wiring a sensor =====

  - Confirm the sensor is a two-wire or three-wire PT100. Do not wire a four-wire PT100 or an NTC sensor as if it were the same sensor.
  - Disconnect power. Compare the A, B, and B′ terminal labels with the two-wire or three-wire diagram supplied for the product, then connect one sensor to one channel.
  - Check the room-temperature reading from the first channel before adding other sensors.

For an NTC 10kΩ sensor, see the [[en-us_products:mpaino_x|X analog input module]]. A temperature transmitter with a voltage or current output also needs the appropriate X input setting.

===== Reading the temperature =====

In Arduino IDE, select your MPAINO board and match the **Temperature Sensor Input Module** option to the shipped F–F5 configuration. This sketch prints the reading of CH0 on the first F module.

<code cpp>
const uint8_t ptChannel = 0;

void setup() {
  Serial.begin(115200);
}

void loop() {
  const int temperature10 = pt100Read(ptChannel);  // Read PT100 temperature as an integer in 0.1°C units
  Serial.print(F("PT100 CH0: "));
  Serial.print(temperature10 / 10.0F, 1);
  Serial.println(F(" C"));
  delay(500);
}
</code>

A return value of ''253'' means 25.3°C. The MPAINO board package includes ''pt100Read()'', so no separate library is needed.

===== If the value looks wrong =====

^ Symptom ^ Check ^
| No change | Confirm the F module is installed, the board option matches it, and the sensor is wired to the selected channel. |
| Large difference from room temperature | Confirm the PT100 type, two-wire or three-wire diagram, and A/B/B′ terminals for the same channel. |
| Second module reads incorrectly | Distinguish consecutive F-only numbers from the shipped allocation in a mixed X/F configuration. |
| ''0'' appears | It may be a valid 0.0°C reading. An absent module, an out-of-range channel, or a failed internal object allocation may also return 0. Check the hardware and configuration as well. |

===== Related pages =====

  * [[en-us_commands:reference:pt100read|pt100Read() reference]]
  * [[en-us_products:mpaino_x|X analog input]] · [[en-us_products:mpaino_y|Y analog output]] · [[en-us_products:mpaino_k|K high-speed pulse output]]
  * [[en-us_products:mpaino|← MPAINO Series options]]