Denford Software & Machines

all thoughts welcome

about two months ago the x stepper on my triac died, got a new one. well last night my brand new 2 month old stepper died.

im aware steppers are pretty hard to kill, anyone got any suggestions? could it be the x parker sd2 drive card causing this?

I would check the wires from the motor. Look for fraying which would cause a phase to short to ground.

um ok thanks, what check it all the way back to cabinet?

is the stepper getting hot (too much current).

Check the connection box is not full of coolant (more likely to cause the drive to fail).

Do you have the tension on the belt too tight.

Is the stepper full of coolant.

Martin wrote:I would check the wires from the motor. Look for fraying which would cause a phase to short to ground.

ok wiring is fine, it is a brand new stepper so

angel-tech wrote:is the stepper getting hot (too much current).

Check the connection box is not full of coolant (more likely to cause the drive to fail).

Do you have the tension on the belt too tight.

Is the stepper full of coolant.

stepper was an exact match for the original one that came with it tom and didn't notice any heat issues.

connection box is perfectly dry and stepper is completely dry.

now like the original stepper its an 8 coil stepper. so only 4 were wired in, just wired in the other 4 coils from the stepper that weren't being used and it works perfect. so it would seem 4 dead coils and 4 working coils.

this is an odd one

changed x and y drive cards over for a 5min test and both seemed fine

I don't think you should have wired it so that 4 coils were not used, the coils are usually wired in series or parallel, but i'm pretty sure they're all used.

angel-tech wrote:I don't think you should have wired it so that 4 coils were not used, the coils are usually wired in series or parallel, but i'm pretty sure they're all used.

they weren't all used on the original stepper we checked

I still have it to be fair

But the eexisting stepper that came from denford only had 4 coils wired not all 8

maybe Martin can shed some light, I would have thought all 8 coils would be wired in to the 4 wires. Maybe you thought the linked coils were just wires not connected. Did you measure the resistance across the coils.

yep we measured all 4 of the not connected one and they were not connected to the machine.

i would love some further guidance

were the unused wires connected to each other in pairs

It does sound strange. I Don't see why we would have left 4 wires seperate.

nope 4 unused wires not connected and each had heat shrink wrap on them

will dig the original stepper out when i get home from work and post some photos

here are, original stepper

as you can see only 4 connected, ignore the white connector we were using that for testing purposes. but as you can see other four have been cut real short and they were covered in heat shrink wrap to stop them shorting etc...

it's normal to have the other four wires short and heatshrunk, but they're normally connected together in pairs, as they're the centre taps of both coils, or end and start of A- A+ and B- B+ coils.

It does seem strange. Was it the X axis on a triac?

Yeah x axis on my triac