Denford Triac VMC with ATC Conversion / Fix

**GEOFFREY** · 22-06-2015

You probably need a starting cap and a run cap. I actualy use a little timer that switches the start cap in for about one second, but the value of the caps you use is dependant on the motor power and if the motor is stating under load etc.. This system does not give a true 3ph, but a "quasi" 3ph, however for a coolant pump I am sure it that you will never know the difference. G.

**Chaz** · 22-06-2015

What is the general consensus for wiring the Emergency Stop Relay. Keep this and its function (X Y Z extreme limits) or wire into the CS Labs directly and control from there?

Currently on activation it stops all drives, the spindle, the coolant pump and the ATC. It works and I am inclined to leave it in place as it is.

**Gary** · 22-06-2015

Keep it as is, but feed an output from the relay into an input on the controller to tell it you have an estop state.

Originally Posted by Chaz

What is the general consensus for wiring the Emergency Stop Relay. Keep this and its function (X Y Z extreme limits) or wire into the CS Labs directly and control from there?

Currently on activation it stops all drives, the spindle, the coolant pump and the ATC. It works and I am inclined to leave it in place as it is.

**JAZZCNC** · 22-06-2015

Originally Posted by Chaz

What is the general consensus for wiring the Emergency Stop Relay. Keep this and its function (X Y Z extreme limits) or wire into the CS Labs directly and control from there?

Currently on activation it stops all drives, the spindle, the coolant pump and the ATC. It works and I am inclined to leave it in place as it is.

Well I don't agree with Killing power because Limit trip isn't an emergency situation it's a positional error so no need to Kill power just Halt movement. SO I would have limits tied to the Enable signal on drives and Inform the Controller of a Limit breach.
This way you don't damage expensive tooling when the spindle grinds to halt inside of material because power is Cut.! Machine is just halted from continuing and you can recovery safely by lifting tooling out of material then reversing off the Switches using tempory overide.

E-stop is an emergency situation to the operator and this is when you want power stopped but often positional errors ie: limits are not life threatening or dangerous to user only potential machine damage and the Limit's prevent this in most cases.

I did wounce upon time think "Kill every thing" but experience as taught me it's not needed where limits are concerened and it's more a pain in the arse, esp with short travels with fast accelerating machine and expensive at times with unnecessary tool damage.

**Gary** · 23-06-2015

With a servo system cutting the power to the drivers if limits are activated is for safety in case you have a servo run away due to encoder loss, but cutting the enable will also work in this situation as well.

Originally Posted by JAZZCNC

Well I don't agree with Killing power because Limit trip isn't an emergency situation it's a positional error so no need to Kill power just Halt movement. SO I would have limits tied to the Enable signal on drives and Inform the Controller of a Limit breach.
This way you don't damage expensive tooling when the spindle grinds to halt inside of material because power is Cut.! Machine is just halted from continuing and you can recovery safely by lifting tooling out of material then reversing off the Switches using tempory overide.

E-stop is an emergency situation to the operator and this is when you want power stopped but often positional errors ie: limits are not life threatening or dangerous to user only potential machine damage and the Limit's prevent this in most cases.

I did wounce upon time think "Kill every thing" but experience as taught me it's not needed where limits are concerened and it's more a pain in the arse, esp with short travels with fast accelerating machine and expensive at times with unnecessary tool damage.

**Chaz** · 23-06-2015

Thanks. I have a question about enabling '0V' for the drives.

Currently, to enable the drives, I need to provide 0V to a certain wire which allows a relay to activate (24V).

I have looked at the wiring diagrams and believe I understand how to wire the limits, E Stop, spindle activate etc.

What I am unsure of is how to enable a 0V grounding to enable the drives. I could reverse the wiring which means that it will switch the relay on, on providing 24V. There seems to be a specific way to do this in the manual as per below. Here, it seems to be for the same purpose but the 24V and 0V are reversed. Is this what I need?

There is also an option for 'low active', does this inverse the logic to satisfy the current need for 0V?

On the topic of the 24V PSU, if you look carefully, there is a bridge there .... :-(

**Chaz** · 23-06-2015

On the topic of 'enabling', for solenoids etc, I assume it will be custom macros and commands to allow various outputs to be switched on and off as needed?

**Clive S** · 23-06-2015

Chaz For the sake of clarity please be aware that the word grounding is not always the same as 0V. Grounding usually what is referred to as the star point ie earth. OV is the -ve from the power supply (but is not always at earth potential). ..Clive

**JAZZCNC** · 23-06-2015

Originally Posted by Chaz

On the topic of 'enabling', for solenoids etc, I assume it will be custom macros and commands to allow various outputs to be switched on and off as needed?

Depends what your controlling to whether it's Commands in a Macro or G-code commands. Both will control Outputs or inputs for turning things on or off.
So for instance to turn on Spindle and Coolant you'll use M3 and M8 which are G-code commands. M5 and M9 will turn them off.

For tool change you'll use M6 which then reads commands in a Script. This is where you use commands to turn on solenoids etc or read sensors etc and position the machine in correct place for tool change.!! . . . . This is where the funs starts.! . . Lol

The Cslabs have a very nice feature in that you can use Modbus to control the I/O directly in the controller and completely separate to Mach3 making it very flexible to what can be done with more features than what Mach3 allows and more reliable.! . . . Bit advanced maybe at this stage but you'll like it one day., ,Lol

**m_c** · 23-06-2015

Originally Posted by GEOFFREY

You probably need a starting cap and a run cap. I actualy use a little timer that switches the start cap in for about one second, but the value of the caps you use is dependant on the motor power and if the motor is stating under load etc.. This system does not give a true 3ph, but a "quasi" 3ph, however for a coolant pump I am sure it that you will never know the difference. G.

One thing to be aware of when using this method, is you have to select caps that will provide reasonably matched voltages between the 3 legs when running. Achieving that with a small motor may prove to be a bit of a challenge, but you should benefit from the fact a coolant pump should have a reasonably steady load.
My main concern would be that the coolant pump motor is running near it's rated capacity, and when running from a static phase converter you risk burning out the motor if you try running it at high loads.