Hi there,

Currently I'm trying to wire my MB3 breakout board and Clearpath servo motor through the Cpm-Cable-Ctrl-Mu120 Cable provided by Teknic. I understand how to wire the step and direction, and  I'm not wiring the enables because I have an E-stop and limit switches. I'm not sure where the wire the HLFB+ and HLFB-.

Does anyone with more experience be willing to help me understand the best way to wire these, as I am a little confused looking at the manual.

Any help would be greatly appreciated,

Starting_Anew

Hi,
HLFB stands for High Level Feed Back and its programmable. Its the Clearpaths (only) feedback to the controller,
most people program it as a 'following error' fault.

Whatever you program it to it should go to an input of the MB3 and that it turn should be monitored by Mach and Mach
should respond appropriately.

Craig

Thanks for the info, and its fine if I dont wire the enables?

Starting_Anew

Hi,
I think you HAVE to wire the enables, at least they have to be hooked to a signal level supply so that the servos work.

What the point of having a motion controller with multiple IO's and then not use them? You need to wire the enable AND the HLFB
to the controller in addition to step/direction.

Craig

here:

https://www.youtube.com/watch?v=QZLwDnGSaeI

is a Video about the Connections, well it is a arduino, but the Prinzipals are the same.

Hi Start_Anew,

I'm an Applications Engineer at Teknic and I happened to come across your post. Hopefully I can help clear up a few things.

ClearPath's "Enable" input controls power to the motor coils. If you don't wire the Enable to anything, the input will always read 0V (i.e. the input will always be de-asserted) and the motor will always be "disabled". A disabled motor will output zero torque (you will be able to freely spin the shaft by hand) and will not complete any commands you send. If the motor is "enabled" (receiving 5-24VDC to the "Enable" input), then it will follow motion commands from your controller.

You should wire the Enable to a 5-24VDC output that can be switched high (5-24VDC) or low (0V).  A quick look at the MB3 manual shows several NPN/sinking transistor outputs that you could wire to the Enable input. You should wire them according to the schematics in the "Input Wiring" section of the ClearPath-MC/SD user manual.

HLFB is ClearPath's configurable High Level Feedback output. The output is optional, meaning you can run the motor without wiring it to anything. Please refer to the "ClearPath Output (HLFB)" section of the ClearPath-MC/SD user manual for more information on how to use HLFB and its different configurations. The MB3 manual shows several optically isolated inputs (they are labeled as PLC inputs in the ClearPath User Manual wiring diagrams) that you could seemingly wire to HLFB. It looks like the MB3 inputs can be wired as sinking or sourcing (HLFB can also be wired as either).

I hope this helps. Feel free to contact Teknic directly if you have any other questions at support@teknic.com .

Best,
Matt C. - Teknic Servo Systems

Thanks very much this clears up alot.

Starting_Anew

Hi,
one of the biggest complaints against open loop steppers is that if they lose a step (or more) the controller
and therefore Mach knows nothing about it and carries on machining without realising that the toolpath
is displaced by a certain number of steps, potentially wrecking the part.

You have gone to the expense of getting servos, an ESS and a MB3. If you don't utilise the HLFB to inform you,
or rather the controller and Mach, that a 'following error' has occurred then what's the point of paying all the extra for
servos?.

You need to, as suggested, read and digest which of the (few) available modes that the HLFB can report back to the controller.
As I posted earlier 'following error' is the most common choice but 'over voltage/'over current' come a close second.

Clearpath servos have elected to have just the one feedback circuit so you cannot have both 'following error' and
'over voltage/over current'. My Delta servos by comparison have up to eight digital outputs and two analogue outputs, so I can
have a range of fault conditions reported back to the controller and also monitor up to two analogue variables, say voltage
and current for example.

Craig

Does anyone know if the MB3 has built in pull-up resistors? I noticed that the ClearPath manual suggests attaching an external pull-up resistor in the circuit.
I have been experiencing a false signal in the inputs connected to my HLFBs every once and a while and I am trying to get to the bottom of the problem. If anyone has a circuit drawing specifically for the ESS and MB3 that they know to be correct, I would really appreciate seeing it!
Thanks for any help!