I have a in-development quadcopter that I’m planning to use for some navigation applications in the future, but right now I’m having trouble getting power monitoring to work. I’m using a Cube Orange, ADSB carrier board, and the power brick that came with it. Voltage monitoring works perfectly out-of-the-box, but current monitoring has been problematic. Full log, param file, and wiring diagrams are attached.
2x Here2 GNSS, both over CAN, positioned exactly as shown in the reference page
Benewake TFMiniPlus LiDAR (reports over serial, powered from PDB builtin BEC)
Using the I2C expander as a CAN expander, which also powers the GPSs and LIDAR off a 5V output from the PDB
T-motor MN4010 Navigator motors (370KV)
14-inch T-motor CF props
Hexsoon 40A ESC (appear to be identical to a T-motor Air 40A)
6S Ovonic 12000mAh 15C LiPo
FrSky L9R S.Bus RC receiver (receiving from a Taranis X9D+)
HolyBro v3 915MHz telemetry radio (talking to Mission Planner on Linux)
The issue is that I have no current report whatsoever. I plugged the included cable (marked POWER2) from the power brick into the Pixhawk’s POWER1 port, and voltage monitoring comes across just fine but current always reads zero, even when at full throttle with props on. I’ve been making these full-power attempts with props on upside down, in an underground garage (it’s what I have available…)
Since I’m pulling more amps than the spec’d max of the power brick, I split the power wire into 4 equal-gauge wires, ran one through the power monitor, and then rejoined them on the other side to split the current equally and measure only one quarter of the total. To compensate for this, I multiplied BATT_AMP_PERVLT by 4, but got zero reading with both that value and the default.
If anyone’s come across this, fixed it, or knows what’s wrong, I’d greatly appreciate your help!
Yup, I’ve been looking around as far as I can find for the last week or so… it is set to cube orange, and the monitor type is set to analog voltage and current.
I’ve also now been able to verify with an external current monitor that there is a signal being sent to the Pixhawk from the sensor that’s representative of the right number… surprisingly, working well below the usual 10A? I’m not sure if this is a noise signal or not (my external monitor only goes up to 3A, so I can’t spin the motors up too much on it), but either way, there’s a 1.7ish mA signal on the current sense pin, which should be showing about 255mA consumption.
[EDIT: will leave this here for context, but disregard it… had the multimeter set incorrectly]
Yeah, I worded it badly, but wondering if I have a bad sensor. Multimeter was set wrong. Can’t get a reading from it apparently… looks like the voltage on that pin might even be slightly negative.
ecalc says about 20 amps hover and about 64 amps maximum.
You should be able to try the power brick-mini without the bypass wires at least for some basic testing.
You params looked OK although I’m not sure about the decimal points in all of those when some are integers. Maybe that’s just a formatting thing - yes the .bin log looks normal
Well… I owe you an apology… my reply to this was still sitting in the drafts when I opened it tonight…
In summary, that also did not work. I hooked up a probe to the current and voltage sense pins, and even though the voltage sense did its job, the current sense pin read a steady zero (milli)volts. Still not sure why this was the case.
Anyhow, I was already planning to move to a Mauch sensor down the road, and this issue just brought up that plan – happy to say it’s installed and working! I did have an unexpectedly high BATT_AMP_PERVLT, but the reading is nearly spot on from 1A through max as expected.
Thanks & apologies for forgetting to click ‘reply’!
