MPXAZ4115A Pressure Sensor

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Technical Data

• * Operating voltage: 4.85V - 5.35 V (Vdc)
• * Current: 7mA - 10mA
• * Temperature range: -40°C - 125°C

• * MPX 4115 Datasheet

Pin Assignment

• * 01 Vout (output) (Pin1 has a notch, see in the picture above right)
• * 02 GND (ground)
• * 03 Vs (voltage)
• * 04 NC (not used)
• * 05 NC (not used)
• * 06 NC (not used)

• Note: Other type "Case 482" or "482A Case"

• It is essential to ensure that no UV radiation by the sensor can invade hole - that would be a disturbance effect! Beware, a laterally mounting allegedly destroyed the sensor!

Pin 4,5,6 (left in picture above) you do not have to solder on this note allows easy removal later if necessary.

Packing the height sensor

• Always ensure that the sensor is protected against turbulent air from the propellers and also wind. This can be done through a hole with an adhesive strip at the sample aperture (make the hole before applying the tape or you could damage the sensor!)

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Activating the sensor in the MK Tool

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When the sensor has been activated in the MK Tool (parameter / configuration screen), values seen in the MKTool should normally be between 800 and 900 and should change if the MK is lifted up or moved down by as little as 10 cm.

Ways to control the sensor

There are three ways to control altitude: preset value, with a slider, or with a switch.

If you want to control with a switch or a slider, you must assign a channel to a poti in the MK Tool parameter / channel screen, and then assign that poti to the airpressure sensor in the parameter/ hohe (altitude) screen.

If you use a switch the you should also activate the function "(Switch for setpoint)" in the parameter / configuration screen.

Other values in the parameter / Hohe (altitude) screen

Min Gas: is the throttle value below which the throttle will not drop if altitude is exceeded. This ensures the MK doesn't come down too quickly. P-anteil: How higher this value, how smaller the ability to exceed the maximum altitude. Luftdruck-D: dampens the variability of the pressure sensor. SMall air pressure changes have larger effect on throttle. Z-ACC: dampens the variabilty of altitude sensing by using the Z-acc value of the accelerometer. Verstarkung: gain. Allows flying at higher altitudes. The setpoint is multiplied by the gain.

Using a fixed setpoint for the altitude

For setpoint (maximum altitude) in the parameter / hohe (altitude) screen you can also choose a value between 0 and 255 to predefine the (maximum) altitude. If you set the setpoint to 0 instead of assigning a poti for the setpoint. That will prevent the MK of fying to high and could be helpful for beginners. Normally however, you assign the poti which is bound to the controling channel.

Flight-activating the sensor with a switch

If you use a switch, just fly to your intended altitude, flip the switch on, increase the throttle (up to 100% if you want to). The MK should remain within cm of the altitude it was at when you activated the switch. If you decrease the throttle the MK will descend - the set point work like a ceiling, not a floor.

BEWARE: if you deactivate the switch, immeditely reduce the throttle, otherwise the MK will become VERY small, VERY quickly.

Flight-activating the sensor with a slider

If you use a slider, then move the slider to about 20-30%, take off and ascend at about 80% throttle until the MK wont ascend any further. Move the slider down, leaving the throttle up. The model should remain at that altitude.

Testing the height sensor

To the height sensor to test, it is as follows:

1st turn on the transmitter and Mikrokopter and the MK tool connecting the sensor as described above to activate. The switch for the amount left to OFF. (If you do not know what the switch position is -> just not as important)

In the 2nd MK-tool the scope so that only gas and HEIGHT are displayed. Scope Start Now. No matter what the value of the height sensor is now, there must be a floating line results. An absolutely straight line means that the sensor is not activated or not properly connected or defective.

3rd Now, after a few seconds have elapsed (the air pressure changes always something), remotely initialize. One sees that the gas goes up (yes we moved the stick) and soon after a jump in the height sensor line. Whether the jump up or down, is actually depending on the weather.





4th Now you should understand the Mikrokopter as far as possible and repeatedly move up and down. A difference in altitude of min. 2m is ideal. As a result we see the scope a sine curve, which approximately commutes around the 0.



Another quick test: It opens and closes the door impact-(window closed). The pressure changes as the peaks are clearly visible.

5th then you can still test if the height function successfully can be activated. They push the gas lever fully upward. The scope is at 230-250 (on trim and dual-rate control of eight). The gas line should be "Off-level scheme" means a straight line. Now turn the system on several levels in a 2 sec cycle on and off. The result is a lowering of the gas line. Moreover, these swings now. With On / Off you get a rectangular signal patterns.

Notes

• The level system works for security reasons only as Gasabschwächer. That is, they can never give more gas than the gas-Stick. For a reasonable level scheme is possible, must contain sufficient gas reserves exist. Because before you turn on the system level usually floats, of course, no rule Reserve, and the MK sink slightly. This is something it up with the channel switching to gas (~ 10%) prevented.

• Remember that the height control with varying load changes again!

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