plasma control panel

Does your hypertherm have an arcOK signal?

Hypertherm has only consumable copy companys in China. Arc okey is not provided in cpc, it's provided in the slow modbuss.
Thermal dynamics has it ok to move signal. I think pin 9 + 10.

HP start's are very bad with watertable for plasma. The cupper+ electrodes are a flop.
I can give you a list of broken air valves around the globe and more wash list's but i don't do this to keep HP save for now.
At the HD section they span the crone.
I am done with HP.

I have read that putting a E-stop between the power supply and the servo drives is a bad idea, Gecko clearly say in there manual that this will damage if not destroy the drive ,

I have also read that putting a disconnect on the AC side of the power supply can damage drives and motors

Disconnecting DC power from a drive is almost always a bad idea but removing the AC from the drive power supply is fine
(how else would you turn them off?)

Gecko says not to put a switch on the DC side of the power supply. So cutting the AC side is OK.

Most estops (even the cheapie from Jaycar) have 2 sides to it. So one side is AC and when pressed stops AC power to the Servo power supply. The other side switches field power to an input to tell Linuxcnc that an estop button has been pressed. You are not allowed to use intermediate relays as they could fail. Your 2 estops should be in series so pressing either drops AC power. I was not keen on running AC power out to the table so I disable the servo drives if it is pressed but yours does not seem to have an input for that.

If I did it again, I'd use an MR series estop from ocean controls becasue you can add extra switch mechanisms to it

The whole estop thing is a bit of a minefield but when I read up on it, there were different classes of estops so choose carefully which one you follow. You don't need to drop power ti the whole electronics, just to the table and disable motion.

I did not seen an ArcOk.

I don't think you really need the 24v to 5v power supply on the THCAD as you can steal 5 volt from the encoder or stepgen. I personally think you'd be fine locating the THCAD in your cabinet with a blow back start machine.

Thanks for the help,

Yeah I missed the ArcOK signal, I checked my Hypertherm manual and pins 12 and 14 are the pins for ArcOK on the Powermax series. In the manual it calls it the transfer signal.

I really do not want to run 240VAC out to the table for the Estop. The Error/Reset terminal on the Gecko 320X drive is a input and a output, When it is shorted to ground it turns power off to the motors,

I think I might just wire the Estop N/O terminal into the Error/Reset circuit and be done with it.

I have revised the drawing, If anyone could check again and if there is anything else that needs to be done let me know.

'03

1. You are not showing any flyback diodes across the relay coils, are they actually there? They are needed.
2. No part numbers for the relays are shown. Please be sure that they all are within the 7i76E drive capability AND total dissipation for each driver chip.
3. I think a pull up resistor to field power on the arc ok input will be cheap insurance on swinging rail to rail, Mine uses an open collector transistor to field power common (0v) and has a 220 ohm pull up.
4. You are not showing it but I am assuming that all your limit,homing, and float switch are wire as normally closed switches.

John

Looks like you have your air scribe relays attached to inputs. Shouldn't they be driven by outputs so you can turn them on? I did not check your 7i76e pins though.

You probably don't need to use a relay for your red and green lights as you can drive them from an output

islander261 wrote:

'03

1. You are not showing any flyback diodes across the relay coils, are they actually there? They are needed.
2. No part numbers for the relays are shown. Please be sure that they all are within the 7i76E drive capability AND total dissipation for each driver chip.
3. I think a pull up resistor to field power on the arc ok input will be cheap insurance on swinging rail to rail, Mine uses an open collector transistor to field power common (0v) and has a 220 ohm pull up.
4. You are not showing it but I am assuming that all your limit,homing, and float switch are wire as normally closed switches.

John

John '03 is using the same opto isolated as I did so its OK for both the flyback and the 7i76e outputs.
We settled on a 1k 1 watt resistor for the pull up but that was driven by the specs of the relay in the everlast machine I had. It was to make sure the current draw exceeded the minimum spec on the relay to prevent oxidisation on the contacts which is a bigger problem than the risk of something floating as intermittent signalling was happening after a period of time.

Once again thanks for the help guys,

John,

Can you explain what the pull up resistor does? Sorry I am new to this kind of electronics,

Rod,

Thanks for the heads up about the air scribe outputs, I did have it drawn as inputs, would of made turning them on hard.

I have attached a third revision drawing for review. I would like to get it right so I can leave it up on this site for others to look at.