Hi,
We are trying to find a power sense module for high voltage and current.
BR Power Sense Module is not enough for us we had to find a module that has 250A max current sensing.
Is there any module with 250a max current sensing compatible with Pixhawk?
Thanks!
Hi @ugurdemirezen,
Thatâs a lot of power. I did some searching and found this discussion, but there didnât seem to be a particular resolution. The closest they mentioned was this 180A one, which is now retired and the closest equivalent is this 90A one.
I asked internally and this 250A one was suggested, which may meet your requirements. Note that the cable they recommend has only 4 wires, and may need to be spliced with something like this cable to be compatible with the Pixhawkâs power port.
If that doesnât work out Iâd guess that youâll either have to find something intended for industrial/large scale use cases (e.g. electric vehicles, home batteries, etc), or make one yourself.
Hi @EliotBR ,
Thanks for the information you provided! It is very helpful.
Do we have to do something to connect with mavlink or is it a plug-play stlye? I mean can we see the voltage and current values in qgc directly when we plugged the cable to pixhawk?
Thanks!
Iâm not sure - I havenât used it before, and the details arenât obvious from the purchasing webpage.
I assume you may need to specify a voltage multiplier, amps per volt, and amps offset in the Power Setup, but Iâm not sure what those values would be - you likely need to look at the sensor datasheet. If itâs not obvious from the datasheet then you can potentially try contacting the manufacturer 
I know that the allowable amperage of the power sensor module currently on sale is 100A.
Do you have any power sensor modules with an allowable amperage of 100A or higher?
This place has some:
I donât have any experience with them though.
Hi @HanJIK,
Iâve moved your post here because itâs on the same topic.
As above, and as @nperry suggested, Mauch-electronic is likely your best bet.
A post was split to a new topic: Power Sense Module questions
The Mauch-electronics page seems to be dead.
After some search I found a 150A(continuous) module here for anyone who is also looking for more powerful current sensor.
Hi @Vete, welcome to the forum
It does seem like theyâve changed their link structure. The web store is now available here:
although it seems that the 250A one I originally linked to is no longer findable (there look to still be some 200A options though).
Thanks for the updated link! 200A is even better.
Itâs strictly not on 100% the topic but the combo unit with 2x200A current sensors (for dual battery) seems interesting with 400A main power switch. 030: PL - 2x 200A PDB / 10AWG â MAUCH Electronic
Does anyone have any experiences with these and/or know where could any documentation on these be found? Or do we have to ask about it from the MAUCH people directly?
Hey,
We developed a high V, high A power sense module for rotary aircraft a few years ago that may work for you. It has the normal plug and play power sense functions, and the same connectors for your flight controller. We added some extra features:
⢠60V, 200A
⢠Dual 5V outputs, on separate rails from vBat to provide a little redundancy
⢠12V, 5A output for sensors
⢠9-30V, 10A tunable output for sensors (we used it at 18V for a LiDAR)
⢠Screw lugs for the battery and load connections
⢠Screw terminal / plug for the aux outputs
I believe it also had some logging features, but I canât remember.
We can resurrect this project bin if anyone needs something like this.
I think I would include some of our new (unreleased) MOSFET switching onto the same PCB. We have a 200A MOSFET for the BROV2 or any other item in the 3 or 4" enclosures, and it may be interesting to combine themâŚ
200A switch would also be very interesting either integrated onto the same PCB or standalone.
When would you think the switch could be available?
We have a 90A Continuous / 200A max MOSFET switch available through FieldWerx that attaches to the o-ring flange in the 3" BLUEROV2 battery tube. See if this is something you could use:
The Mauch page has gotten an overhaul and is working, I recently ordered these in the picture, a 200A sensor with power supply.
Eliot, do you know which pin options that correlate to the original pins for voltage and current on the Power port of the Navigator. When selected Other sensor the options are as follows:
Disabled
A1
A2
Pixhawk
A12
PX4
Unknown: 4
Iâve managed to get a voltage reading (I think), But the current doesnât move under increased load.
Edit. I found the parameters in the Autopilot parameters as BATT_VOLT_PIN and BATT_CURRENT_PIN, when edited to 3,4 or 2,3 if indexed from 0 still nothing.
Hi @IntoTheBlue -
I believe youâre asking for this pinout, which is listed in the Technical Details section of the Navigator product page:
Pins 3 & 4 are used for current and voltage sense, respectively. Youâll also need to adjust the parameters to properly map the signal to the measured voltage and current. BATT_AMP_OFFSET and BATT_AMP_PERVLT control the current measurement. The powerswitch calibration extension, intended for the BlueBoat, may be helpful when trying to determine these parameters!
Yea, thanks, I know the physical pin, but if it could be named differently in the parameter list than 3, 4âŚ
In blue OS I was not allowed to type in 3. In QGroundcontrol it is possible. It labels 3, if I type in 3 manually as Pixhawk/Pixracer/Navio2/Pixhawk2_PM1, doesnât feel to comforting.
4 as Unknown: 4
Yes, Iâve used the Calculate button together with actual measured values. Voltage seem healthy, Current not. Even if I adjust it down to a reasonable level it doesnât move when I put a load on the circuit.
The power sensor gives out 2,6V on the voltage pin, which seem reasonable to be tuned to 26,7V of the batteries real Voltage.
The current pin on the other hand gives the signal of 3,7V, when the actual current draw is 0.16A. 3,3V is maximum no?
I had a look at that Extension, maybe could be useful when I get closer to a proper reading.
Hi @IntoTheBlue -
You donât need to specify those pins anywhere⌠what parameter are you trying to modify? Overriding something with a value of 3 or 4 is not going to get things working. Itâs also important to note that the output signal youâre trying to read needs to have a maximum of 3.3V to be read by the ADC - higher than that will damage the Navigator!
If you donât know the BATT_AMP_OFFSET or BATT_AMP_PERVLT, the extension I mentioned can help you determine them - you input the power being drawn by the system and it determines the offsets to reach that expected measurement.
Are you using a recommended autopilot for ArduSub?
BlueOS should be drawing from the relevant parameter descriptions in the firmware - not sure why the power pin description is outdated. Thanks for mentioning this - Iâll flag it internally so we can fix it
If it is necessary to specify a non-standard value for a parameter (e.g. if you have a custom firmware, or the descriptions / known valid values are outdated), you should be able to do so by selecting the âCustomâ checkbox when editing that parameter, and the âForceâ option if youâre certain itâs right but itâs not part of the values/range that the frontend knows about / is set up to verify.
If thatâs not working, please let us know (ideally by raising a new bug report Issue) so we can look into and fix it
I use the Navigator.
When choosing Power sensor as âOtherâ you have to make some manual choices.
Elliot had the answer, 4 and 5
The first power sensor that I hooked up delivers 3,7V no matter the current. I consider it faulty. I ordered two, the other behave reasonable. I can see the voltage out increasing when I run a 500-thruster dry. I used the Extension you referred to, I will go with that setup for now. I guess I can make a better calibration when I can apply more load.
I havenât managed to get the Battery monitor in BlueOS to increase the reading of drawn Amps though. It is a bit discomforting, but I need to proceed.
