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Thruster Commander no PWM signal out

I’m having problems initializing the basic ESC. When I power on, there are the three beeps from the T200 but then the ESC is not beeping at all, therefore not initializing.

The green power light on the Commander is on. The potentiometer is conected to SPEED and in the middle possition, the ESC signal wire is connected to RIGHT OUTPUT and the SWITCH is set zo ON.

Although on the Commander the output connector is labeled with 5V I just measure 3.6V between the 5V and GND connectors.

My configuration: Single T200, Basic ESC, Thruster Commander Powersupply 5S with 40A cont. current max. for ESC and Commander.

Thanks a lot for supporting me.

Hi @boris.waldis,

The way the ESC ‘beeps’ is by vibrating the motor at the desired frequency - that is the ESC beeping. As specified in the Learn tab of the ESC product page, the first three beeps (rising in pitch) indicate that the ESC has detected all three phases of the motor. The next two (which you’re currently not getting) happen when the thruster receives a consistent ‘neutral’ signal, which should be from a PWM signal with a 1500us pulse duration.

This seems valid, although you may wish to double-check that the white signal wire from the ESC is connected to the ~ signal indicator, and the black wire is going to GND. It may also be worth moving the potentiometer a bit to each side to see if the neutral point is a bit offset.

The middle pin on the output connectors (labelled with 5V) is actually an input, and is unused with our ESCs. It can be used to power the thruster commander with ESCs that have an internal BEC and provide a 5V output wire, as specified in the Powering the Thruster Commander section of the Thruster Commander Guide.

I’m a bit confused here because our connection diagram specifies 7-26V of input power, which matches the ESCs rating and makes it seem like the thruster commander might be able to take that range too, but everywhere in the text (on the product page and guide) that powering the thruster commander is mentioned it specifies 7-20V (a fully-charged 5S battery outputs 21V). I’ve asked our engineering team and will get back to you if this is likely to be an issue. It’s at least unclear documentation that we need to fix.

I would personally expect that 21V at least shouldn’t break it instantly, so if double-checking the potentiometer position doesn’t help you may wish to send a photo of your setup so we can see if anything looks incorrect. If your setup is fine and the commander itself is not working as intended then you can email support@bluerobotics.com and link them to this thread, to discuss a potential refund/replacement :slight_smile:


Thanks a lot for your quick reply.

As you suggest I will double check the signal wires and test my setup with different poti positions.
On the other hand pls inform about the correct power specs for the Commander. Thanks.

Unfortunately I do not have any osci so I’m not able to check any signal coming out of the Commander.

If my error diagnostics is ineffective I will send you a photo of my setup.


I checked the signal wires. Seems to be ok.
I checked the power supply. For the 18650 are not fully charged I get about 17.6V. Nevertheless I changed the supply for the Commander to proper 5V.
I moved the poti as adviced with no result.

I still can’t manage to initialize the basic ESC.

Please find some pics of my setup.

I’m having exactly the same problem! Just received the Thruster Commander pack and parts, and no matter how much I analyze and follow the documentation and try every possible config and approach and initialization process, I get nothing but the 3 beeps on startup and the green power LED.

From your photo, it looks like the potentiometer is plugged in the ‘Speed’ terminal. Move it to the ‘Right In’ terminal, and give it a go.

I asked about this and was told

It’s worth noting that while our ESCs are rated to 7-26V input, our T200 thrusters are only rated up to 20V, so given you’re using one it seems relevant to stay within that rating regardless of the rating for the Thruster Commander board itself.

The POWER header input requires 7V or more, because it’s regulated down from there to the 5V that the board actually runs on. If you want to provide a direct 5V supply it needs to be via one of the 5V pins on the ESC (OUTPUT) headers.

Because the connections to the ESC(s) are outputted PWM signals, I don’t believe the Thruster Commander can tell whether there are ESCs connected, so I expect this won’t make a difference (SPEED control is supposed to be able to control both left+right together). In saying that, it doesn’t hurt to try if nothing else is working :slight_smile:

It may also be worth moving the switch jumper to the OFF position, since that is also expected to output a neutral signal to the ESCs, which should allow them to arm. If that then works to get the remaining two beeps then at least we know the commander microcontroller outputs are working, in which case there may be some issue with the potentiometer or something.

Welcome to the forum @jkwm42 :slight_smile:

As above, the 3 beeps indicate that the ESC is receiving power and has detected all three phases of a motor, and the green power LED shows that power is plugged in to the thruster commander. The next two (missing) beeps are supposed to indicate 1) valid signal detected, and 2) valid ‘neutral’ (1500us pulse duration) signal received - motor armed and ready for control. If you have access to an oscilloscope you can try measuring the signal on the output pins and seeing if there’s a PWM output or just nothing.

If you’re not getting at least the ‘valid signal’ beep then either something is wrong with your setup (e.g. ESC connected backwards, potentiometer not plugged in, etc) or the thruster commander board is damaged. If you’ve tried the above recommendations and are confident your setup is valid then I’d recommend you email support@bluerobotics.com and link them to this thread. If it’s determined your commander board is dead on arrival/damaged despite having been used correctly then they’ll be able to set you up with a replacement/refund :slight_smile: