Re: Denford Triac Spindle Issue
Update:
With slider at TAC = spindle fires up to high revs and sometimes trips my supply RCD!
If it doesn't trip the RCD, I can usually (not every time) start/stop the spindle in VR5, but not alter rpm.
With slider at AVF = spindle fires up to lower revs (1k rpm?) then stops.
I am not able to start/stop the spindle in VR5.
Wires #54 & #55 removed from Sprint1200 = spindle does fire at all
Wires #54 & #55 linked out on #1 & #3 connector on Sprint1200 = same as with #54 & #55 in position (incl same with the TAC/AVF slider)
At startup, both TAC/AVF, I measure 11.5v across #54 & #55
The only spindle settings I can see in VR5 are max/min rpm, and check boxes for manual, speed pot & external speed pot...
Help!
Re: Denford Triac Spindle Issue
I think you should contact sprint for advice .
I found they were a helpful bunch
Re: Denford Triac Spindle Issue
It sounds like there is some kind of isolation issue with the drive speed control.
If the drive speed control is being connected to ground, then that can cause an RCD to trip.
The speed control circuit on these kind of drives sits around half of mains voltage, so if you connect it to 0V/GND (the control electronics will typically tie 0V to GND), then you've just created an earth leakage which an RCD will detect, but as it'll be pretty low current, it may not always be enough current to trip the RCD.
I wonder if the isolation on the controller has failed.
A manual fix, would be to install a potentiometer to control the spindle speed. There is a slim possibility that I may still have a suitable potentiometer kicking around the workshop, but I won't have any time to look until next week, as I'm working at an event all weekend.
Re: Denford Triac Spindle Issue
Quote:
Originally Posted by
m_c
It sounds like there is some kind of isolation issue with the drive speed control.
I wonder if the isolation on the controller has failed.
A manual fix, would be to install a potentiometer to control the spindle speed. There is a slim possibility that I may still have a suitable potentiometer kicking around the workshop, but I won't have any time to look until next week, as I'm working at an event all weekend.
From what I can see sprint 1200 is a non isolated drive .
I am told that a potentiometer should control speed even directly connected but it will be supplying an input at the mid point of 170v or so. if you want to send signals from the computer there has to be an intervening board .
Re: Denford Triac Spindle Issue
Quote:
Originally Posted by
John11668
From what I can see sprint 1200 is a non isolated drive .
I am told that a potentiometer should control speed even directly connected but it will be supplying an input at the mid point of 170v or so. if you want to send signals from the computer there has to be an intervening board .
There is an intervening board. The Baldor controller that Denford fit to their machines.
However I'm not sure if the Baldor controller does the isolation, if there is a separate isolated supply for the Baldor controller specifically for the speed control, or if the analogue speed control is done by a totally separate board.
There is also the added complication that this machine has been upgraded from it's original serial controller to a USB controller, so I don't know how much may have been changed from the wiring diagrams that are available on the Denford forums.
I know KB drives of that era often had an option for isolated inputs, but I don't think Sprint did.
GingerNinja, have you traced where the 54/55 wires go to? Do they connect to the controller, or do they connect to the drive rack?
Re: Denford Triac Spindle Issue
You can replace with the i1200 or i1220 Sprint Drive. I went this way as my board wasnt functioning on my previous Triac.
Re: Denford Triac Spindle Issue
I would certainly recommend the 1220i model. It is simple to connect, but dont go for a new one until you have established that your existing one is faulty,
You need to see if it will respond to an external run switch and a potentiometer.
1 Attachment(s)
Re: Denford Triac Spindle Issue
Ref 54 & 55…
They run from Sprint drive to the drive rack, above the USB board
Attachment 30498
Spent a short amount of time, doing some more investigation…
When booting up mill and spindle ramps up, SGR is NOT energised.
With SGR removed, spindle still goes rogue and ramps up on its own!
Removed #54 & #55 from green bar at lower end…
With spindle stopped, 180mV across terminals.
176mV @ 1000rpm
182mV @ 2000rpm
185mV @ 3000rpm
185mV @ 4000rpm
Haven’t got a 10k pot yet for other tests, but will do so soon.
There is an intervening Baldor board.
I’m waiting for Sprint to come back with some more info/prices…
I happy to go with either the 1200 or 1220i… they aren’t ‘megabucks’, but if it’s the Baldor board, it could still be a waste of cash… so still trying to prove what’s what.
Re: Denford Triac Spindle Issue
You have to get the i version otherwise you will blow devices. Ask me how I know this ...
Re: Denford Triac Spindle Issue
Quote:
Originally Posted by
Chaz
You have to get the i version otherwise you will blow devices. Ask me how I know this ...
The original drive Denford fitted is non-isolated from the factory, so whilst the 1220i may be an upgrade, the 1200 should work fine… shouldn’t it?
‘How do you know you need the i version?’