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Author Topic: Denford Triac still waiting (patiently) to run  (Read 401 times)

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Denford Triac still waiting (patiently) to run
« on: January 05, 2021, 02:15:50 PM »
Hi everyone.  My name is Steve Harris and I’ve just joined this forum although I have been looking at it for some time.
If you check out my introduction, on page 277 of “New people!! Come in here and introduce yourself, then you will better understand my predicament.
I have a Denford Triac miller which I have been converting over the years. It’s been stood now for 10 years without me doing anything to it.
 Have fitted various bits of hardware and the specification so far is as follows:
½ hp (0.37 kW) motor on the spindle as supplied with the machine. X and y motors are 100 watt brushed DC and a 120 watt brushed DC on z axis.  Toothed belts fitted to each, 3:1 ratio.  Panel contains 3 Geko G340 servo drives.  Each axis motor is fitted with a Hewlett Packard HEDS-5500 optical encoder. A DC power supply is fitted to supply the axis motors at 18 volts via the Geko drivers. There is also a 5 volt power supply unit, which was free so I put it in, but not used (yet!!)
I have a Mitsubishi VFD for the spindle drive.  I also have a “Digispeed-XL ver 5.1” from Homann Designs (Australia) for control of spindle speed via the VFD. The machine has its original limit ad home switches (see below).
Some of the wiring is complete; I have used screened cable where appropriate, and am OK with completing this. All the limit switches are the original micro type switches.  The homing switches are 2 wire proximity type. They are Balluf units and very compact. And there was one used as a spindle speed sensor but this has escaped!
My problems now are what to use for connection to the computer in the way of a breakout board (and do I need anything else in between?). 
I believe the circuitry for these Balluf proximities was all on the original control board, long since gone as it was badly burned up when I had it. Is there anything I can use to interface these or would it be easier to fit another type that would communicate with a new breakout board. I would also need a spindle speed sensor.
I see that some of the latest breakout boards have all manner of control and inputs so could anyone advise me please as to what I should do to get it going.
Thanks in advance for any information.
Re: Denford Triac still waiting (patiently) to run
« Reply #1 on: January 05, 2021, 03:00:29 PM »
Hi,
to determine what hardware is most appropriate we need to know what the hardware has to do.

In particular you say that you have Gecko drives for the servos. What model and what specs?
That will determine what signals the drives require which in turn determines the best mix of hardware to use.

Craig
My wife left with my best friend...
     and I miss him!
Re: Denford Triac still waiting (patiently) to run
« Reply #2 on: January 05, 2021, 03:24:33 PM »
Hi, Thanks for the prompt reply.
The Gecko drives are G340 DC servo drives.  The information is in the support section of the Gecko website.
Not sure what else you need to know. ??
Regards. Steve Harris
Re: Denford Triac still waiting (patiently) to run
« Reply #3 on: January 05, 2021, 07:50:34 PM »
Hi,
OK, the G340's are Step/Dir drivers and are capable of up to 250kHz pulse input.

Depending on the resolution of the encoder you may well require Step pulses of 100kHz.

What are the specs of the encoders? How are the servos coupled to the leadscrews? These two will determine the resolution, which
will in turn determine the max signalling rate.

Machs parallel port is still popular because its free, the downside is that it runs ONLY on 32bit Windows 7 and earlier PCs,
and they are a vanishing breed. Second drawback is that its default pulse speed is only 25kHz which in all probability
will not be adequate for driving your servos.

I would recommend an external motion controller like an Ethernet SmoothStepper (4Mhz) or a UC300 (400kHz)  or a 57CNC (125kHz).
All of these devices have Mach4 plugins and unless you are invested in Mach3 for some reason then I would recommend  Mach4. All development
on Mach3 ceased six years ago and not withstanding that it still works and has a loyal fanbase it is obsolete.

Note that the UC300 and Ethernet SmoothStepper require a breakout board, and the 57CNC benefits from one. Depending on the level of
sophistication you can pay as little a $20 for a single port equivalent BoB up to $200 for a fully developed three port equivalent BoB.

Craig
My wife left with my best friend...
     and I miss him!

Offline Tweakie.CNC

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Re: Denford Triac still waiting (patiently) to run
« Reply #4 on: January 06, 2021, 01:11:53 AM »
Quote
Mach4. All development on Mach3 ceased six years ago and not withstanding that it still works and has a loyal fanbase it is obsolete.

Just a correction...

Mach3 is Obsolescent it is not Obsolete (there is a difference).

Tweakie.
KEEP SAFE !
Re: Denford Triac still waiting (patiently) to run
« Reply #5 on: January 06, 2021, 11:45:04 AM »
Hi,   Encoders are Hewlett Packard HEDS-5500 2 channel optical, pulse width error, count frequency 100kHz (MAX)

Toothed belt drive to leadscrews (5mm pitch) 3 : 1 reduction.

I have had a word with the UK smooth stepper agent and he has them in stock so I think I will go with one of those.

Looking around for a suitable break out board

I have to source a new laptop as mine is not powerful enough but ones with an ethernet socket seem to be in short supply.
I will use Mach 4 as suggested.
Thanks again.
Regards.  Steve Harris