add UB sensor PF output to docs

Signed-off-by: Martijn Govers <Martijn.Govers@Alliander.com>

Author: mgovers

docs/user_manual/components.md

@@ -569,6 +569,10 @@ with the highest probability.
 | ----------------- | --------- | ---- | ------------------------- | :------: | :------: | :---------------: |
 | `measured_object` | `int32_t` | -    | ID of the measured object | ✔ | ❌ | a valid object ID |
 
+#### Output
+
+A sensor only has output for state estimation. For other calculation types, sensor output is undefined.
+
 ### Generic Voltage Sensor
 
 * type name: `generic_voltage_sensor`
@@ -603,6 +607,10 @@ voltage is a line-to-line voltage. In a `asym_voltage_sensor` the measured volta
 
 ##### Steady state output
 
+```{note}
+A sensor only has output for state estimation. For other calculation types, sensor output is undefined.
+```
+
 | name               | data type         | unit     | description                                                                                                              |
 | ------------------ | ----------------- | -------- | ------------------------------------------------------------------------------------------------------------------------ |
 | `u_residual`       | `RealValueOutput` | volt (V) | residual value between measured voltage magnitude and calculated voltage magnitude                                       |
@@ -688,6 +696,10 @@ See the documentation on [state estimation calculation methods](calculations.md#
 
 ##### Steady state output
 
+```{note}
+A sensor only has output for state estimation. For other calculation types, sensor output is undefined.
+```
+
 | name         | data type         | unit                       | description                                                                  |
 | ------------ | ----------------- | -------------------------- | ---------------------------------------------------------------------------- |
 | `p_residual` | `RealValueOutput` | watt (W)                   | residual value between measured active power and calculated active power     |