Node TigWelder

PoE powered Node on AC voor de Tig Welder.

Normal operation

Turn ON

1. Check both pressure dials. They should both show pressure.
   1. If not - they may be empty and someone before you may have not bothered to replace the bottle. Baad. Check by turning the welder on and trying to weld.
   2. If that works - then you may have to fix the leak or report this to the mailing list - so it can be fixed.
2. Open valves
3. Swipe tag
4. Turn on with the switch on the front

Turn OFF

1. Turn off with the switch on the front
2. Close BOTH Values
   1. Node beeps to remind you to do so.
3. Press the button on the torch shortly to confirm you've closed BOTH' valve
   1. Node will stop beeping
4. Check the pressure
   1. If it is below XXX - arrange for a replacement bottle and report this to the mailing list.

Do not unplug the welder; leave the power cable in the wall socket. We use this to track gas leaking and usage.

Trouble Shooting

No Gas ?!

1. Are BOTH valves open ?
2. Do the meters show pressure
   1. If not - you've ran out of gas. Arrange for a replacement -and- report to the mailing list. Be wary of the 125L limit.

Swipe ok - but does not want to turn on

1. Do you see waiting for card on the display ? If so - it has not read your card (yet).
2. Did you hear a beeb when you swiped ? If so - your card is picked up ok.
3. Did you hear 3 or more beeps when you swiped ? If so - your card is not getting permission from the system
4. Does your personal page in mijn.makerspaceleiden.nl show that you have permission ?
5. Is the internet in the space up and running ?

The Machine does not want to accept my badge

1. Do you hear a beeb when swiping ? If so - it has read your card.
2. Did it work on the door ?
3. Does it work on any other machine ?

Resetting the Node

Unplug the main power cable of the welder from the wall scocket, wait 10 seconds and then re-seat it.

Wait about 10 seconds until you try again.

Trouble shooting

The first QR code will bring you to this page. The second QR code will show you the logs in a browser. You can also telnet to the IP address shown in the 'MORE' display to see the log in real time.

See this page for more details.

Electronics

De node is AC powered; en zit 'voor' alle electra van het TIG apparaat.

OPTO1 wordt gebruikt om spanning na de on/off switch the detecteren.

OPTO2 wordt gebruikt om de spanning van de drukknop op de toorts te detecteren.

Het SSR relay onderbreekt de spanning naar de on/off schakelaar.

De node is gebaseerd op de Black 2025 boards. Machine specific wiring:

• SSR relay voor power
• 12V digitale output voor de klep
• Opto voor spanning
• Opto voor detectie lassen

Solenoid Wiring

12V solenoid with on-current reducer

The 12V solenoid uses about 0.5 Amp/6Watt when fully engaged. This makes it relatively hot; and also is a stretch for the AC/DC power unit used. So after a high on-peak current- we reduce this to about 1/3 once engaged with a resistor. See https://www.electronicdesign.com/technologies/analog/article/21798400/whats-all-this-solenoid-driver-stuff-anyhow for details.

Board jumpers and settings

Board - serie nummer 4

1. Rework 1 - verwijderen ESD diodes antenne
2. Rework 2 - omdraaien transistors programmering

Note: een van de program-transistors is vervangen door iets willekeurigs

Jumpers:

1. Vint, 12 volt
2. Vpoe/SS - all off

Green Connector

PIN	Description	Use
1	CUR2	NC
2	CUR2	NC
3	OPTO 4	NC
4	OPTO 3	NC
5	OPTO 2	N for torch sense
6	OPTO 2	Torch sense
7	OPTO 1	N for voltage sense
8	OPTO 1	Voltage sense
9	L input	L, connected
10	N input	N, connected
11	Relay 1 NO	L power
12	Relay 1 Common	N
13	Relay 2 NO	NC
14	Relay 2 NC	NC
15	Relay 2 common	NC

Checklist node

Doel checken is

1. Machine mag niet anders aan gaan dan met de schakelaar voorop
2. Powercycle van de node moet geen rare situaties opleveren
3. Spanningsonderbreking moet machine in veilige stand brengen.
4. Timeout na X minuten moet de machine ook in veilige stand brengen.
5. Machine mag nooit uit (of aan) gaan zonder gebruikers actie. Dus node/netwerk/etc verlies of een timeout mag niet leiden tot uitgaan of aangaan van de motor.

Stappen:

1. Powercycle de node. Komt die terug op het netwerk ?
2. Na powercycle; kan je de unit niet aan zetten ?
3. Swipe, check dat de machine werkt. Zet hem uit. Onderbreek de stroom > 1 seconde en controleer dat de machine weer in de veilige stand staat.

Source code

https://github.com/MakerSpaceLeiden/AccessSystem/lib-arduino/ACNode/examples/TigWelderNode

Bypassing the node

With the explicit permission from a trustee - a node can be bypassed. For example when it is broken. There are two dip switches on the board.

Obviously - doing so without the express permission is a sure way to loose your membership.

Bill of material

AC/DC 12V	~2€
Solenoid 12V	~9€
Current coil	~1.50€
Connector	~1.50€
OLED display	~3.50€
Buttons x3	~0.30€
Solid state relay, 40A	~7.82€

History

Build late 2024