The Q172DSCPU is a dedicated motion CPU within the Mitsubishi Q-series. It handles up to 16 axes of servo control with a 16 k-step servo program capacity and 3200 positioning points, supporting both direct and indirect specification. I/O is capped at 256 points total, shared between discrete and analog. The CPU mounts in a Q-series base and requires DC 20.4 to 26.4 V; internal 5 V consumption is 1.44 A. Inputs are sink/source via photo coupler isolation with a threshold of DC 17.5 V / 2.0 mA. For an integrator: this CPU occupies one slot in the Q-series rack and can drive up to seven extension base stages. The built-in 4 general-purpose inputs and 1 emergency stop input are connected via AWG 22 wire. No fieldbus interface is included – motion control is over the Q backplane; additional network modules (CC-Link, Ethernet) must be added separately.
Sourcing & lifecycle posture
The Q172DSCPU is classified as 'mature' – still supported and manufacturable, but not a current new-design recommendation. It remains available through standard distribution, but lead times can extend beyond typical active modules. For a BOM freeze or existing line, confirm availability against your required quantity. This is not an obsolete part, but we recommend quoting to order to secure lead-time and avoid line-down gaps.
Application note – what the ratings mean
The 16-axis control is the headline capacity – this matters if your machine has more than a few axes. Each axis can be independently positioned with linear or circular interpolation if needed. The 256-point I/O limit includes both local and remote I/O on the Q bus; be sure to account for module occupancy in your base configuration. The 3200 positioning points (indirect specification possible) allow large coordinate arrays to be stored and recalled without reprogramming – useful for complex motion profiles. Servo program memory of 16 k steps should be sufficient for most stand-alone sequences but may be tight for very long, branched programs.