[ericks]

Well.....my machine is not working properly. First time in five years it seems to be "missing" steps on Y-axis. It all started after i had a "floating" earth. I was using an extension lead to supply power to the shed, got a little shock off the toggle switch on my control panel. Did some checking and found the extension lead having a broken earth conductor somewhere inside the cable. Anyway i finally installed power points in the shed and the earth problem is all sorted but now the Y axis is not holding position. Already eliminated mechanical "slip". I think possibly damage to the Y axis driver.....busy looking into this

Any advise ideas welcome

[adam_m]

I'm not familiar with the individual driver setup such as yours since I use a G540 but I would switch a driver and re-run a test and see if the problem follows the driver switch. At least that will help narrow down the problem..

Adam,

[ericks]

I'm not familiar with the individual driver setup such as yours since I use a G540 but I would switch a driver and re-run a test and see if the problem follows the driver switch. At least that will help narrow down the problem..

Adam,

Thanks Adam, i changed it over earlier today....haven't had a chance to test it. Will run a test program tomorrow

[john-100]

looking at your 2nd photo I see the stepper driver enable is not being used -
drive enabled by default so that's one less thing to check

after double checking the power supply and stepper motor wiring on the faulty Y axis driver
I would swap the the Y axis step & direction BOB connections to another axis (say X axis)
and vise versa

re assign the step & direction in ports and pins
( assuming your running mach3 on a PC )

that way you can check to see if its the Y axis stepper driver or BOB and /or PC that's at fault
depending on your test results

John

[wizard]

I would not completely dismiss mechanical issues! This especially if you only have one axis messing up.

Looking at your pictures (on a cell phone) at the moment, the controls layout doesnt look that bad. A few things to consider though.
1. I like to see twisted pairs run from the power supply to the drives.
2. Review all internal connections in the control box. Connections do come loose over time and with normally functioning electronics about 80% of failures are electronics related.
3. Make sure signal and power lines do not run in parallel.

In any event this phone just doesnt allow me to see much, the suggestions above are common control panel issues, especially the loose connections. The axis swap ideas are good ones just be careful about assumptions that the swap solved something. What i mean here is that ive seen situations where a swap solved a problem not due to a new drive but simply due to reseating the electrical connections.

One other point, ive become a big believer in wire furrules anywhere set screw type terminals are used. This especially in the smaller gage wires. Yes in an ideal world this requires a crimper for those furrules. It is surprising how a wire can break off yet look like it is properly seated in a connector. Sometimes it is worth it to check every wire into every connector. Usually i give them a little tug.

[ericks]

looking at your 2nd photo I see the stepper driver enable is not being used -
drive enabled by default so that's one less thing to check

after double checking the power supply and stepper motor wiring on the faulty Y axis driver
I would swap the the Y axis step & direction BOB connections to another axis (say X axis)
and vise versa

re assign the step & direction in ports and pins
( assuming your running mach3 on a PC )

that way you can check to see if its the Y axis stepper driver or BOB and /or PC that's at fault
depending on

John

Thanks....the power supply tested fine, stepper motor wiring fine, i actually went through all the wiring. Yes i am running Mach3 on the pc

[ericks]

I would not completely dismiss mechanical issues! This especially if you only have one axis messing up.

Looking at your pictures (on a cell phone) at the moment, the controls layout doesnt look that bad. A few things to consider though.
1. I like to see twisted pairs run from the power supply to the drives.
2. Review all internal connections in the control box. Connections do come loose over time and with normally functioning electronics about 80% of failures are electronics related.
3. Make sure signal and power lines do not run in parallel.

In any event this phone just doesnt allow me to see much, the suggestions above are common control panel issues, especially the loose connections. The axis swap ideas are good ones just be careful about assumptions that the swap solved something. What i mean here is that ive seen situations where a swap solved a problem not due to a new drive but simply due to reseating the electrical connections.

One other point, ive become a big believer in wire furrules anywhere set screw type terminals are used. This especially in the smaller gage wires. Yes in an ideal world this requires a crimper for those furrules. It is surprising how a wire can break off yet look like it is properly seated in a connector. Sometimes it is worth it to check every wire into every connector. Usually i give them a little tug.

Thanks for the advise, like i said the machine has been running faultlessly for the last five years. Thus i don't expect the wiring to be an issue. However i will follow your advise for sure

[john-100]

very often cables fail within an inch (25mm) of a connector or cable gland , fitting a cable relief will help
intermittent motor and power connections usually damage the stepper driver

cable chains will help when they can be fitted , but expect any cable that is constantly flexed to break eventually

I have spent more time ( about 60%) of my time re-making video & audio cables used in studios and on location
than repairing the broadcast equipment
(quite often camera men would damage the multi-way connectors on the lens servos by twisting & pushing the connector until the key way lined up ! )

John

[ericks]

Thanks guys....looks like the culprit is the bob
Installed another board, hope to test it properly soon

[ericks]

Had the time to make a few parts on the machine today.....very happy cause the machine is back working like it should

[Sterob]

Did you replace with the same model BOB?

[john-100]

a working machine -
a great result

john

[ericks]

Did you replace with the same model BOB?

I originally had a Homann designs breakout board, now i am using the low cost 5 axis board

[ericks]

a working machine -
a great result

john

It sure is.....here is a pic of the controller with the new bob, i used the opportunity to tidy up the wiring/connections a bit.