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

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.

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 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.

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);
}

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.

ILOGICS Product Documentation

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