Maxirouter PWM

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AlanC1959
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Maxirouter PWM

Post by AlanC1959 » Mon 27 Jun , 2022 18:38 pm

Hi, I have bought a 10W diode laser from Endurance Lasers, it requires a PWM connection for turning the laser on and off.

Can anyone help me locate one on the Maxirouter please?

Here's a link to a picture of the Baldor board:

https://www.dropbox.com/s/skrxe03j9k1p6 ... 5.jpg?dl=0

Thanks in advance

Alan

Martin
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Re: Maxirouter PWM

Post by Martin » Tue 28 Jun , 2022 12:09 pm

The Baldor NextMove does not have any PWM outputs.

You could use a normal output if you are just turning it on off.

I have attached a link to the NexMove connections.

viewtopic.php?f=54&t=2126

AlanC1959
Posts: 17
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Re: Maxirouter PWM

Post by AlanC1959 » Tue 28 Jun , 2022 17:44 pm

Thank you Martin, are you saying I could use pins 2 & 3 of the Power Out to provide ground and +12v to run it?

If so, how would I address those pins in software / gcode please?

Alan

DavidB
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Re: Maxirouter PWM

Post by DavidB » Thu 30 Jun , 2022 21:58 pm

If you look in the NextMove manual, it's easy to find online, it gives the max current output for the 12V at 10mA so it's not going to power your laser and likely can't be turned off while the board is running. I presume you're going to use the laser in place of the router so what about using the SGR (Spindle Go Relay) if it's like other Denford products. In those one side of the relay coil is connected to 24V and the relay energised when the other end of the coil is pulled to ground with an open collector driver. Maybe keep 12V power to your laser when in use to keep fans etc running if necessary and use a PWM signal which can be manually set but goes to 0% when the SGR is not active. Using SGR means any time the spindle is active your laser will be so no change in the gcode.

AlanC1959
Posts: 17
Joined: Tue 09 Jun , 2020 15:08 pm
Hardware/Software: Denford Maxirouter
VR Milling v5.69
Location: Cleethorpes, UK

Re: Maxirouter PWM

Post by AlanC1959 » Fri 01 Jul , 2022 11:25 am

That helps a lot

Thank you very much

Alan

AlanC1959
Posts: 17
Joined: Tue 09 Jun , 2020 15:08 pm
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VR Milling v5.69
Location: Cleethorpes, UK

Re: Maxirouter PWM

Post by AlanC1959 » Thu 21 Jul , 2022 9:10 am

DavidB wrote:
Thu 30 Jun , 2022 21:58 pm
If you look in the NextMove manual, it's easy to find online, it gives the max current output for the 12V at 10mA so it's not going to power your laser and likely can't be turned off while the board is running. I presume you're going to use the laser in place of the router so what about using the SGR (Spindle Go Relay) if it's like other Denford products. In those one side of the relay coil is connected to 24V and the relay energised when the other end of the coil is pulled to ground with an open collector driver. Maybe keep 12V power to your laser when in use to keep fans etc running if necessary and use a PWM signal which can be manually set but goes to 0% when the SGR is not active. Using SGR means any time the spindle is active your laser will be so no change in the gcode.
The output doesn't need to power the laser, just to signal on, off and power level.

I can't find any reference to the SGR in the Nextmove ST manual, or is it external to the Nextmove ST?

The laser suppliers have said to use the SOUT & SGND, but they show 1.28v when the spindle is not running, and 8.48v when it's at full speed.

The manual says there's a variable resistor on SOUT, is it on the rear side of the board?

If the variable resistor is adjusted, won't that affect the use of the spindle when I need it?

Thanks in advance

Alan

AlanC1959
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Joined: Tue 09 Jun , 2020 15:08 pm
Hardware/Software: Denford Maxirouter
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Re: Maxirouter PWM

Post by AlanC1959 » Sun 14 Aug , 2022 10:45 am

Hi, I'm still working in this.

I've got the laser working using SOUT and SGRND, but unfortunately that means that when the head is travelling, the laser leaves a feint line between cuts, because it's still receiving a small voltage.

The laser and cooling system are powered completely independently, so I only need to provide 0v to 12v to control the power level.

The laser system will be powered off when the spindle is in use

Is there any reason that SOUT outputs 1.28v when the spindle is idle?

Can't it be adjusted so that it provides 0v, or will that impact the spindle operation?

Alan

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Re: Maxirouter PWM

Post by DavidB » Tue 16 Aug , 2022 19:37 pm

Why not use the spindle enable relay (SER) output mentioned in the 3rd post in this thread viewtopic.php?f=39&t=2395 to gate your SOUT signal, making sure that when not enabled the power input level goes to 0 for safety. How that is achieved I'll leave to you to determine as I have no knowledge of the laser power level input circuitry.

AlanC1959
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Re: Maxirouter PWM

Post by AlanC1959 » Thu 18 Aug , 2022 12:30 pm

DavidB wrote:
Tue 16 Aug , 2022 19:37 pm
Why not use the spindle enable relay (SER) output mentioned in the 3rd post in this thread viewtopic.php?f=39&t=2395 to gate your SOUT signal, making sure that when not enabled the power input level goes to 0 for safety. How that is achieved I'll leave to you to determine as I have no knowledge of the laser power level input circuitry.
Thanks for your input David, ideally I need to output 0v for laser off and 12v for maximum power, with a variable output in-between to control laser power

I've got it all connected now, but with the "spindle" off, because it still outputs a 1.28v when off, the laser leaves a feint line when travelling, because the laser doesn't get turned off completely, I'm not sure that the SER can provide a variable voltage, can it?

If absolutely necessary, the feint lines could be sanded out, but obviously I don't want to do that.

In addition to the output from SOUT, the laser is turned on and off independently via a separate control, power & cooling unit, I'm unsure what you mean by "gate your SOUT signal"

The other issue I have, is that because I am turning the "spindle" (laser) on and off between cuts, when it's turned on again, it pauses for a fraction of a second before it starts cutting, this is leaving a scorch mark at the start of each cut.

I'm told this pause is normal for a milling machine, but is not desirable for a laser cutter.

Is there anyway of turning this pause on and off on the fly through code, or would I have to change the machine setup?

Alan

DavidB
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Re: Maxirouter PWM

Post by DavidB » Thu 18 Aug , 2022 15:47 pm

If the laser information I read is correct then it really wants a PWM input between 5V and 12V with reference to the GND connection in which case tying it to any voltage between 5V and 12V will give you full power as it's effectively a 100% PWM, maybe you could use a voltage to PWM converter. By 'gate the SOUT' I mean to use the SER or its control signal to switch SOUT yourself, in its simplest form the SER may have a spare contact that you could use to switch SOUT directly. Likely you'll find a delay/pause command after the M03 in the gcode to allow the spindle to get up to speed, whether that's configurable in the software you're using I don't know.

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