Hello everyone, I made wiring diagrams for interfacing my Mitsubishi Servo Drive with a 1212C DC/DC/DC CPU and SM1234. Before I start wiring everything, I want to clear up some doubts.

1. [Background] I plan to use a lab-grade linear DC-regulated power supply (0-30 [VDC], 0-5 [A]) to supply power to the CPU, SM, ATO Digital Load Cell Amplifier, Output 0-5V/RS485, and my safety circuit (consisting of a Phoenix Contact two-channel safety relay, two Allen Bradley force-guided relays, a 2NC e-stop, and a momentary push button to reset this circuit). I made a power budget and found that I would need to supply 14 [W] at 0.59 [A] to keep everything running. The PSU has a Ground wire output that I want to connect to a Ground DIN-rail mount terminal block.

   1. [Question] Since the CPU, SM, and safety circuit components will sit on the same DIN rail, is the Ground terminal block enough to keep all those components grounded? What I have on the wiring diagram now is a jumpered connection between the CPU GND and M (X10 3 and 2) that connects to the remaining connection point of the Ground terminal block. From here, I connect any shielded cables (at one end) and unused AI to 0 VDC (common) since it goes to ground from my last statement. Is this correct?

2. [Background] TC is an Analog Torque Command that takes in +/- 8 V signals. VLA is an Analog Speed Limit that takes in +/- 10 V signals. LG is the Control Common for TC and VLA. Since SM1234 outputs +/- 10 V, I use a voltage divider to drop the voltage to +/- 8 V for TC. The end of this voltage divider is connected to 0 VDC (common) since it goes to ground.

   1. [Question] I show TC, VLA, and LG as shielded twisted three wires in my diagram. I understand that a shielded twisted pair is good at reducing noise, but I don’t think twisting three wires has the same effect. Would I be better off keeping the three wires separated and instead adding tin-copper sleeving around the three-wire bundle?

   2. [Question] I’m not exactly sure how to connect LG. My thought was to connect it to both Commons (0M and 1M) of each analog output. Is this correct?

3. [Background] My safety circuit diagram is based on Figure 14 of the Phoenix Contact Safety Relay Datasheet, titled “Emergency stop monitoring/manual, monitored start” (you can download the datasheet in the original link I provided). EM2 stands for Forced Stop, which decelerates the servo motor to a stop when activated. EM2 is a DI.

1. [Question] I followed along with a YouTube video to understand the wiring diagram, so hopefully, what I have adheres to what is shown in Figure 14. I plan to use another pair of contacts on the safety relay (23 and 24) to interface with my Servo Drive. In my first wiring diagram, my CN1 DIs are connected as Sourcing since the DI common (DICOM) is connected to 0 V DC while the inputs connect to 24 V DC. Going back to the safety relay, I have contact 23 going to 24 V DC to complete the circuit and contact 24 going to EM2. Does this sound right, or do I have these connections flipped?

Any insight/help will be much appreciated. Thank you!