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--- en:automation:02-glossary:analog-inputs-hidden [2020/05/07 12:46] – [Measuring resistance] avsetula
+++ en:automation:02-glossary:analog-inputs-hidden [2025/10/10 11:11] (current) – added edge ofojt
@@ Line 2: / Line 2: @@
 Analog inputs (AI) are for measuring analog values such as DC voltage, current and resistance. These values are produced by sensors which indicate multiple states such as thermometers, tensometers, distance meters, lux meters etc.
+----
+<html><span class="kbBlueText">More information about analog inputs can be found in specific categories:</span></html>\\
+<tile>
+| en:hw:004-edge:02-description-of-io:04-description-of-ai    | Edge               | :en:hw:unipi-kb-icon-edge.png       |
+| en:hw:007-patron:description-of-io:04-description-of-ai     | Patron             | :en:hw:unipi-kb-icon-patron.png     |
+| en:hw:01-axon:description-of-io:04-description-of-ai        | Axon               | :en:hw:unipi-kb-icon-axon.png       |
+| en:hw:02-neuron:description-of-io:04-description-of-ai      | Neuron             | :en:hw:unipi-kb-icon-neuron.png     |
+| en:hw:03-unipi11:description-of-io:04-description-of-ai     | 1.1 & 1.1 Lite     | :en:hw:unipi-kb-icon-1.png          |
+| en:hw:04-extensions:description-of-io:04-description-of-ai  | Extension modules  | :en:hw:unipi-kb-icon-extension.png  |
+</tile>
+/*
 ===== Analog inputs on Neuron and Axon =====
 The functionality of AIs on Neuron and Axon is different on Group 1 and Group 2/3 and Neuron extensions.
@@ Line 32: / Line 47: @@
 {{:en:automation:02-glossary:unipi_ai.png?300|}}
-R_sens = the sensor itself
-R_ref = the resistor
-<WRAP center round tip 60%>
+   R_sens = the sensor itself
- For reading temperature between 200-3800R (-200°C/+800°C), a 1K resistor should be used to ensure the voltage will not exceed 10V.
+   R_ref = the reference resistor
-</WRAP>
-The value at the AI is calculated using the following formula
+There is also a input resistor inside of the AI with the value:
-''R_sens (200) = 12V/969.7 + 200)*969.7 = 9.948V''
+   R_ai = 12200ohm
-''R_sens (3800) = 12V/(969.7+3800)*969.7 = 2.439V''
+<WRAP center round alert 60%>
+For R_sens >= 200ohm, use R_ref = 1k. For R_sens < 200ohm, use R_ref = 10k
-When the -200°C temperature is measured, a 9.948V voltage is present on the AI, while with the +800°C temperature the AI voltage will be 2.439V. To verify those values, please check the documentation of your sensor.
-<WRAP center round info 60%>
-Please keep in mind the ability of Unipi 1.1's architecture to precisely measure voltage is limited at voltages below and including 0.05V. For our showcase sensor, the resulting deviation could be up to +-50°C. If a more precise measurement is required, change the R_ref value accordingly.
 </WRAP>
+The value at the AI is calculated from the voltage you read from the AI (V_ai)
-If the R_sens value does not match the requirement, you need to change the R_ref setting. The R_ref value is calculated using this formula
+             Vcc - V_ai     R_ref * R_ai
-''Rx = (R_ref*12K8)/(R_ref+12K2)''
+   R_sens = ------------ * --------------
+                V_ai        R_ref + R_ai
-When setting the R_ref, please ensure that at maximum/minimum resistance the voltage at AI+ will not exceed 10V or decrease below 0V.
+The Vcc is the applied voltage (12V in the picture above).
+*/