Disabling drive when not in use

[rkonnen]

I am trying to figure out the best way to disable the drives when your not using them. I looked at Mariss' dump circuit, it turns the main transformer off. Any other suggestions.
Thanks,
Richard Konnen

[rutexus]

Richard,

I don't know of any way to disable the Rutex drives other than to remove the VC (+24vdc). If you remove the VM (motor power), when you return on the motor power the drive will try to correct, and if the motor is not where it was when the drive was disabled, the motor will take off heading towards the position it was when it was turned off. LOOK OUT!

Tom Eldredge
Rutex LLc

[rutexus]

Richard,

I just thought of something...I believe if you pull the ERR (pin 8 of the db15) signal low (to ground) it will disable all of the drives. Try that out on the bench. I may get time to try it out myself today.

Tom Eldredge
Rutex LLC

[rkonnen]

Tom I have not finish my cabinet yet, but I was wondering if you were able to test out this idea using the #8 pin.
Thanks,
Richard Konnen

[vebers]

Hello

I have a brake on my Z axis that is reqired for my pneumatic Draw bar. This break is switch controlled and If I forget to release it and try to move the Axis I get to see that magic smoke everyone is talking about. If grounding the 8 pin will disable the drive without loosing location this could be a God send for me. (2 Drives and $440.00 later) any way if this works please post results. Incedently is there any way to fuse these things so that you don't loose a board in a crash?

Vince

[jed102]

I too would like to here if anyone has had success disabling the rutex drivers?

Frank

[MaxHeadRoom]

Commercial drives traditionally always incorporate an enable input, this is necessary in e-stop and for other interlock uses, such as following error detection output circuits.
Al.

[rutexus]

Gentlemen,

I did not test pulling pin 8 low to disable all of the drives. The only way that I know of is removing the +24 vdc.

I recommend that the current trip values be set lower than I had previously recommended because of the limited heat sinking capability of the drives through the black anodized aluminum plate. For the R2020 drives I would not set the current peak limit to over 60 and for the R2010 drives, I would not set it to over 30-35. The Rutex drive current limit is designed to prevent this "smoke" from being produced if the maximum current is reached for more than 2 seconds. After driving at the maximum current limit for 2 seconds, then the drive will reduce the pulse width of the drive signal to a level to keep it under the current fall back setting. I usually set the current fall back to 10 on both drives. This is just so that I can use a handwheel to move the axis back from whatever it is jammed up against.

I have found in my own testing that the heat sink area right behind the mosfets heats up very quickly at the maximum current and then the mosfets blow. So, I reduce the current trip setting so that if I jam the axis up against a solid wall of some type, and the drive starts torquing at the maximum current, the mosfets get warm, but not hot enough to blow themselves up. I did some experiments and found that the above values seem to be safe enough in the drive motor configuration I am familiar with.

Tom Eldredge
Rutex LLC

[jed102]

Thanks Tom, I will connect switches to the 24v supply for each driver.

Thanks also for fixing my r990H drivers under warranty, ...they are working great. Great customer service! Looking forward to the dro capability eventually.

Frank

[UKRobotics]

Has anyone tried the 'grounding of pin 8' thing yet, and if so does it work ?

Also does grounding pin 8 or removing 24v power disable the parrallel port outputs ?