Output of IO pins

Chenglong

Hello everyone,

I am using Duet 3 MB 6HC to control a UV curing module(0V for turning on, 24V for turning off). I use "M950 P3 C"io6.out" to define the output IO port number. Then I use "M42 P3 S0/S1" to control whether this port can output.

However, when I send "M42 P3 S1" to the system and use Voltmeter to measure the output voltage, the value is almost equal to 0 but not 3.3V as the document said. And I use a Boost module to increase output voltage, it also don't work.

So I want to ask whether I used M-CODE incorrectly or am I missing some necessary operations？

I am looking forward to your reply.

dc42

@Chenglong you can't use a boost converter to boost a 3.3V output to 24V.

Please provide a link to the data for the UV curing module so that we can advise you now best to control it from the Duet.

Chenglong

@dc42 Please look the link: https://dymax.com/products/equipment/light-curing-equipment/spot-curing-systems/bluewave-qx4-v2.0.

Thanks for your time.

dc42

@Chenglong thanks. Which control input to it are you trying to use: the PLC interface, or the footswitch input?

Chenglong

@dc42 the PLC interface

Chenglong

@dc42 Now, I use the OUT5 GND port to control the UV module——I add <M950 P3 C"out5”> to config.g，and define M14.g: M42 P3 S1, M15.g: M42 P3 S0. And connect V_OUTLC1 to the module's V＋，connect out5 to the module's V-.

However, when I run the M14 in the system, two errors appear: G0/G1 insufficient axes homed; 12V under-voltage event（8.9V）. For the second error, I just test the output voltage of out5 which I use, it equals to 12V, so I don't know whether it is because of other out port.

dc42

@Chenglong said in Output of IO pins:

Now, I use the OUT5 GND port to control the UV module——I add <M950 P3 C"out5”> to config.g，and define M14.g: M42 P3 S1, M15.g: M42 P3 S0. And connect V_OUTLC1 to the module's V＋，connect out5 to the module's V-.

Do not connect V_OUTLC1 to the module's V+, you might blow things up if you do that.

It looks to me that the PLC connector has NPN-style inputs. I suggest you connect OUT5- to the PLC connector input pin that will control the UV. Also connect a ground wire between ground on the PLC connector and Duet ground.

Chenglong

@dc42 Thanks for your advice and I just connected OUT5 port to the PLC's input+, GND port to the PLC's input-. Then I use M42 P3 S1 to let ports output, but it didn't work at all, and I use voltmeter to measure the voltage between OUT5 and GND, it seems to be 0. Is there any mistake?

Chenglong

@dc42 About the two errors: G0/G1 insufficient axes homed; 12V under-voltage event（8.9V）, do you have any solution?

dc42

@Chenglong the 12V under-voltage event means that either you overloaded the 12V regulator on the Duet, or that the VIN voltage dropped to below about 11V. This will have caused the stepper drivers to lose position, so RRF set the axis status to "not homed".

Chenglong

@dc42 I understand. So how can I solve this problem?

Chenglong

@dc42 Because the UV module requires 24V to close it, and out_5 on Duet 3 MB 6HC can only output 12V, so I just connect it to a DC-DC converter.
At first, I used io_out(3.3V), however, the converter min_input voltage is 4.5, so converter didn't work. Then I choose out_5 because out_1-3,7-9 are used.![alt text]

Chenglong

@dc42 Could you help me solve this problem?