Triac PC spindle motor speed varies by its self

[amaxlegend]

I have had the Triac PC for at least 10 yrs helping me to build Loco bits and bobs.
The spindle speed is now varying by its self.
I was advised that it may be a capacitor on the spindle control board was going bad .
I replaced all the capacitors on the board ( the round can type ones )

This didnt cure the problem

Does any one have a solution or idea where to go next .
regards Alex

[Steve]

Measure the 0-10V DC analog input to the spindle drive.

It should be 10V at max speed. 5V at half speed. Is this voltage going up and down or stable?

Next measure the DC motor voltage going to the motor is this going up and down?

It could be motor brushes or the motor tachometer

[Martin]

What is the requested spindle speed?

[amaxlegend]

Measure the 0-10V DC analog input to the spindle drive.

It should be 10V at max speed. 5V at half speed. Is this voltage going up and down or stable?

Next measure the DC motor voltage going to the motor is this going up and down?

It could be motor brushes or the motor tachometer

Thank for your reply
I have taken the cover off the spindle motor
not sure what wires do

they are marked from top t1 then t2 then k1 then k2 then a1 and the bottom one a2
t1= blue (thin) t2 red (thin) K1 Blue (thin) K2 (thin) a1 blue (thick) a2 Brown (thick)

measured a1 and a2 @250rpm 61-62vdc (varies) then @4000rpm 70-73vdc (varies) seems really high.

as I increase the speed to 4000rpm it doesnt seem like it is going at 4000 rpm seems much slower
and varies. If it was a petrol engine I would say "its hunting " so to speak.

not sure if I have got the correct wires to test but as the a1 and a2 are much thicker thought they may be +and - , just guessing as I dont have a diagram .

any help would be greatly recieved.
Alex

[amaxlegend]

What is the requested spindle speed?

Using the software Vr milling, it varies at all selected speeds with the slider, when in jogging mode.

any help would be great I just dont know where to start , now that I replaced all the metal little round capacitors with the correct values on the spindle controller board.
had a look at the 4 motor brushes and they seem ok as do the 4 tac ones there wasnt any black stuff floating around and everything looks clean, the bearings look good as well.
regards Alex

[Steve]

Can you make the voltage measurements on the spindle drive and report?

[Martin]

You could try adjusting the Stability pot on the Sprint 1200 spindle drive.

[amaxlegend]

Do you know which pair does what, and what the voltage should be ?

[amaxlegend]

Measure the 0-10V DC analog input to the spindle drive.

It should be 10V at max speed. 5V at half speed. Is this voltage going up and down or stable?

Next measure the DC motor voltage going to the motor is this going up and down?

It could be motor brushes or the motor tachometer

do you have a diagram to pinpoint the position of the 0-10v dc analog input to the spindle drive. etc, as Im working in the dark on your suggestions, its like , I know that you can get a bus into town, but need to know where the bus stop is located and what number is on the bus , otherwise if I jump on the first bus that comes along, it could take me anywhere lol.
I'm at the passenger level not the bus driver , who knows his route lol

I appreciate your help enormously
Alex

[TDIPower]

Not sure if this will help but I uploaded the drawings for a sprint controller, may not be the same though viewtopic.php?f=46&t=4778

Pete

[Steve]

Please send a larger picture of the spindle drive.

Download electrical diagrams
file:///C:/Users/soddy/Downloads/TriacPC-Electrical-Drawings.pdf
View page 36
Wires 54 and 55 are the analogue

spin drive.JPG (46.2 KiB) Viewed 143270 times

Wires 17 and 19 look like the motor DC

[amaxlegend]

The voltage on those Pins at 250 (slowest speed ) is 4.6 -4.78 DC , fluctuates
the voltage on the pins at 4000 (highest speed ) is 6.7 - 7.32 DC , fluctuates

It doesnt get near to 10vdc on full speed

wonder why that is ?
regards Alex

[amaxlegend]

Not sure if this will help but I uploaded the drawings for a sprint controller, may not be the same though viewtopic.php?f=46&t=4778

Pete

Thanks Pete but I dont have the wire/ volt settings to see if they are similar , but will have a look at yours
Many thanks Alex

[amaxlegend]

Please send a larger picture of the spindle drive.

Download electrical diagrams
file:///C:/Users/soddy/Downloads/TriacPC-Electrical-Drawings.pdf
View page 36
Wires 54 and 55 are the analogue

spin drive.JPG

Wires 17 and 19 look like the motor DC

The voltage on those Pins 54 (-) and 55 (+) at 250 (slowest speed ) is 4.6 -4.78 DC , fluctuates
the voltage on the pins at 4000 (highest speed ) is 6.7 - 7.32 DC , fluctuates

It doesnt get near to 10vdc on full speed

wonder why that is ?
regards Alex

[Steve]

Can you supply photos of the inside of the electrical cabinet It sounds like the spindle analog card has failed.

[amaxlegend]

Can you supply photos of the inside of the electrical cabinet It sounds like the spindle analog card has failed.

inside case and board pics for triac

[amaxlegend]

You could try adjusting the Stability pot on the Sprint 1200 spindle drive.

ok will try this over the weekend
regards
Alex

[amaxlegend]

Can you supply photos of the inside of the electrical cabinet It sounds like the spindle analog card has failed.

Hi Steve whats the solution . is there a replacement available or can you replace a component ie what needs fixing or replacing

Do you have the wiring diagram for this machine that you can send me.
regards Alex

[amaxlegend]

Please send a larger picture of the spindle drive.

Download electrical diagrams
file:///C:/Users/soddy/Downloads/TriacPC-Electrical-Drawings.pdf
View page 36
Wires 54 and 55 are the analogue

spin drive.JPG

Wires 17 and 19 look like the motor DC

Hi Steve cant realy read this as its a bit blurred any chance you could send me the pdf for the Triac as it would be useful to have. do you have any other documentation on the triac
regards Alex

[TDIPower]

You should be able to prove if its the sprint by disconnecting the 0-10v from the denford control and just wiring a pot as per the diagram for the sprint I pointed you to. that way you can manually alter the speed and see if it stays stable or hunts. If it is fine then it points to the problem being from the denford 0-10v. At least that way you know where to look.

Pete