1988 Triac conversion

[John S]

Doing a conversion on a Triac to Mach 3.
This one has the Lynx 08 DC drive fitted.

Connections are as follows:-

Four large terminals, mains in [ 2] and DC out [2]
Then a strip of smaller logic connectors. Only 5 of these are wired up.
The 3 for the pot which have 10.2 volt to the end ones and two marked Torque.



Can anyone shed any clues on how to connect up to a breakout board please?
I did a search on Triac, Lynx and DC spindle but came up empty.

Many thanks
John S.

[Triac whizz]

you'll need a spindle speed controller

https://www.cnc4pc.com/Store/osc/index.p ... 7f67a821b9

but I don't know anything about the controller you have I usually find that just after getting the existing drive sussed out and running it goes & dies!

[John S]

Thanks,
I already have a spindle speed controller. I'm using the C11G board from the same people.
What I'm looking for is how to switch the speed board on and what pot wires to use.

Most PC controlled gear uses 0- 10 volts for the speed but the Denford has 3 wires.
I can probably experiment and try two of these but do the 2 wires in 5 and 7 marked torque ? switch to board on ?

I'd like to find out before I blow it up

Spent all last night doing a search on the forum but only found one reference to this Lynx board and that had no details.

John S.

[Mr Magoo]

Hi John...

Be carefull about connecting the Lynx drive up to your controller.
I remember that some of the spindle drives used had the 0-10v analogue into the drive is not isolated from the mains. I am not sure if the Lynx was one of these.
But if so, this means terminal 2 on the drive (Min) is not at 0v but is floating and referenced to a mains (240v) potential.

If the C11G board has its anlogue out referenced to ground then you can expect a bang! Check the C11G output is not referenced to ground.
I have seen some analogue isolators which go inbetween the Analogue output and the spindle drive to resolve the problem, but not sure where??

[John S]

The C11G board is totally isolated provided you use a dedicated 12 volt power supply just for the 0 -10 volt analog bit.
We have exactly the same problems on the Sieg X3 machine which can also be at mains.
That part shouldn't be a problem it's how to switch the board on.

The Lynx is live all the while once the main contactor goes in. I could connect a pot up as shown on the board wiring and then short 5 and 7 out to see if this will start it up.

I was hoping someone somewhere had dealt with these before.

John S.

[Denford Admin]

I have put the manual into downloads:

viewtopic.php?t=1666

hth

[John S]

Many, many thanks.

Just what I needed and it confirms what i thought 5 and 7 start it and the pot goes on a combination of 1 2 and 3

I'll post the diagram later so it's on record.

Thanks again.

John S.

[Mr Magoo]

Hi John,
For what it's worth, the existing spindle analogue setup got its supply from terms 1 & 2 on the drive, then feed the analogue back into term 3.

Maybe this is good for you if terms 1 & 2 are giving 12v ?

[John S]

Don't you mean "got it's supply from 1 and 3 and fed it back into 2 ?



The speed part of the C11G board has 4 terminals two are 12V + &- and the other two are ground and 0 - 10 volts analogue. This part of the board is isolated from any other voltages.

On the Sieg machines we feed this board a completely separate 12 volt supply so it's isolated from anything else in the circuit. Then the ground is fed to ground on the pot connection, in this case pin 3 and the 0 - 10 volt is fed to the reference pin, in this case pin 2. pin 1 is left unconnected.

Hopefully tomorrow if I get my order from RS Components I may have this running.


John S.

[John S]

Oopps my mistake, I misread the legend on the board yes it is 1 and 2 for the control voltage and 3 back in for the analogue.

Got this machine all finished now, pic's tomorrow.
The spindle works but not correctly using the spindle board supply.
This supply under load on pins 1 and 2 reads 10.3 volts, now if this was to be fed back in via a pot to pin 3 then it would work fine and get full speed.

However feeding this 10.3 volts into the CNC4PC C11G board, by the time it gets out again to the analogue you are limited to only about 7 volts.

Carefully checking the circuitry the Lynx board is isolated so we could use the spare 12v connection we had from the power supply [ this is definitely a no no with the Sieg boards ]

Using this 12 volt input the C11G board is now able to put out 10.8 volts giving a spindle speed of 2,800 rpm.

So we now have all three axis under Mach 3 control together with the spindle off / on and speed. The tool changer has been left for a later day but a simple switch has been fitted to work the power drawbar and that's interlocked with the E Stop.

John S.