Berd-air

mark

I decided to try the Berd-air system a few weeks ago and ordered the parts I though I needed, including the air pump and one of these from ebay

Now everything has arrived (weeks later from china etc) and I realise I can't find the guide that led me to by the parts I did! I have found this guide https://forum.duet3d.com/topic/4477/24v-pump-can-i-connect-direct that I can follow by buying the additional parts, but is there any way I can use the part of bought from ebay - ie connect the fan to the bed mounts, dc in to power supply and the control (white wires) to the fan output on the board?

Sorry if this is a stupid question, I am not electronics savvy

Thanks,

Mark

mark

I have been doing more research and realise that the previously linked mosfet might not work, however could I use https://www.ebay.co.uk/itm/15A-400W-MOS-FET-Trigger-Switch-Drive-Module-PWM-Regulator-Control-Panel-UK/293280226312?hash=item4448dd1c08:g:FBEAAOSwAZ9bbvy9 My query comes because the mosfet has ground and pwm, but from what I can see the duet has + and pwm

I would wire it directly but I am not sure how I get 5v for my hot end cooling fan and 12v (V IN) for the air pump - from what I can see the voltage jumper affects all the fan voltages

Mark

grizewald

The Duet switches the negative side, so the PWM pin on the Duet is switched to ground. Therefore, you'd connect + to your MOSFET's PWM input and ground on the MOSFET to the Duet's PWM pin.

For your hot end cooling fan, get a 12V one.

mark

Thank you

grizewald

My pleasure!

dc42

The simplest way to use a BerdAir if you are not using all the heater outputs is to connect it to a spare heater output, along with a flyback diode in parallel with the motor. Then use the M106 A parameter (RRF 2) or M950 F parameter (RRF 3) to configure a fan on that heater output.

mark

@dc42 Thanks, I have searched ebay for a flyback diode but I have no idea what to buy. Would you be able to provide a link or product number so I can get the correct diode (sorry I don't have a clue with electrics)

Mark

grizewald

@mark A 1N4004 diode will work just fine. You can get a pack of 10 from eBay UK for 99P plus postage. See: https://www.ebay.co.uk/itm/1N4001-1N4002-1N4003-1N4004-1N4005-1N4006-1N4007-General-Rectifier-Diode-DO-41/312730999168

mark

@grizewald amazing, ordering now

grizewald

@mark You might also find this page illuminating: Flyback Diode

Note that you must connect the diode with the cathode to the positive. On all the 1N series diodes (and 99% of diodes in fact), the cathode is marked by a ring at one end of the package:

alt text

mark

@grizewald Thank you, I will have a read and see if I can get my head around what they do. I was aware that they were directional, but thank you for confirming which way they need to go.

Hopefully this thread will also be useful to others who are struggling to understand what is required. I can do mechanical (designing my printer basically from scratch) but electronics are over my head!

Nuramori

I thought that a fly back diode was not needed with duet2 boards that are newer than version 1.02

mark

I believe that if you use a heater output then it is needed.

Mark

Dougal1957

and it can't hurt to fit one anyway.

dc42

@mark said in Berd-air:

I believe that if you use a heater output then it is needed.

Correct. Flyback diodes are built in to the fan outputs only.

matej1006

Hello @mark how it's blow air it's good or not.
I want use same principle Berd air with pwm regulation
but i will have like maks 2m of tube to blow through will work this or not please let me know?
Thanks Matej

Macwolf

@dc42 said in Berd-air:

The simplest way to use a BerdAir if you are not using all the heater outputs is to connect it to a spare heater output, along with a flyback diode in parallel with the motor. Then use the M106 A parameter (RRF 2) or M950 F parameter (RRF 3) to configure a fan on that heater output.

I have in my config. entered the following ->M950 F0 C"e1heat" Q500--M106 P0 S0 H-1
is that right?

dc42

@macwolf that looks OK to me.