I have a RMC70 with QA1 quad inputs. I am getting the encoder input from a Yaskawa Sigma II servo drive. In RMC Tools help I see an imput impedance of 215 ohms. In the Sigma II manual I see a terminating resistance of 220 - 470 ohms. Long story short im not getting my positions back from the servo drive and I think this is my problem. I think I need to add an interface card between the two. Something like your RB12 modules. Any other suggestions?
The exact value of the termination is probably not the problem.
My guess is that the output type is not compatible with our input type or something is not wired correctly.
Does the Sigma II have an RS422/485 type output (5 Volt differential driver)?
From their manual:
I think my wiring is ok. I’m going to get my scope out and make sure I’m getting pulses out of the servo. I will re-double check the wiring then.
Just an update.
After talking with Yaskawa and going through all my settings they still thought it was wiring or something in the RMC. I was unable to put my scope on the output. I found out that as a scopes mature they grow legs and run away from home. So I didn’t have a scope to look at the pulses with. Any way I have a good fluke meter and I think I should be able to see some change on the signal and I could not. So I think it’s the drive. So Yaskawa tech support wants to set up a conf call with Delta, Yaskawa and myself. So we pick a time and I ask Don Denman to join us. I’ve worked with Don a lot and I tell him what I have done and what I think about the problem. So before the conf call I setup my computer opening RMC Tools and the drive software. We do the call in and Don has a good idea. He sets up an online meeting so they can both see my computer. This is a great idea. In about 3 minutes he has sent us emails with the info and we are all attached. First thing we do is give control of my computer over to the Yaskawa guy. In about 2 minutes he finds a setting that disables the encoder output. We change it and now I see counts. We go on for another 20 minutes or so talking about counts per rev and max speed of the system etc.
So long story short Don didn’t fix my problem but he let me use his tools to get the job done.
I am still not clear if I can wire the servo directly to the rm75e? or does it have to go through another device?
In this case, the quadrature input on the RMC75E QA module was able to be directly connected to the encoder output on the Yaskawa drive. The problem was that the Yaskawa had ben set to disable the encoder output. Turning it on solved the problem, and the RMC was able to get the signal from the Yaskawa.