Description
Key Technical Specifications
| Parameter | Specification |
|---|---|
| Part Number | 7264 |
| Module Type | 4-Channel SSI Interface Module |
| Number of Channels | 4 independent SSI channels |
| Supply Voltage | 12–48 VDC |
| Max Output Current | 4.0 A |
| Logic Input Level | TTL PWM |
| Max PWM Frequency | 20 kHz |
| Resolution | Limited only by the connected position sensor |
| Position Functions | Preset, count direction, position scaling, latch input |
| Operating Temperature | -20°C to +85°C |
| Interface Type | SSI (Synchronous Serial Interface) |
| Compatible Sensors | SSI-output absolute encoders and position sensors |
| Country of Origin | USA |
Product Introduction
The AMCI 7264 is a 4-channel SSI interface module designed to bridge absolute encoders and SSI-output position sensors directly into a PLC-based control system. Rather than requiring a dedicated motion controller or high-speed counter card to decode synchronous serial data, the 7264 handles the SSI clock/data handshake on each channel and presents the position value as a parallel digital word that the PLC can read in a single scan. This is particularly valuable in multi-axis applications — web guiding, converting lines, packaging machinery — where four or more absolute position feedback points need to be monitored simultaneously without consuming excessive PLC scan time or requiring specialized motion programming.
The module’s resolution is determined entirely by the connected sensor, meaning it scales from 12-bit to multi-turn absolute encoders without any internal limitation. Key features include position preset (allowing the PLC to establish a reference zero), count direction control, position scaling for engineering-unit conversion, and a latch input that captures position data at a precise external trigger event — critical for registration marks, cut-to-length, and flying shear applications. The 12–48 VDC supply range and -20°C to +85°C operating temperature make it suitable for industrial environments. AMCI, now part of the broader motion control ecosystem alongside Rockwell Automation partners, has long specialized in encoder interface and stepper control solutions for packaging and material handling, and the 7264 remains a practical choice for legacy systems and new installations alike where SSI encoder integration is required.
Troubleshooting Quick Reference
| Fault | Likely Cause | Relevancy | Quick Check | Fix |
|---|---|---|---|---|
| No position data on a channel | Encoder not powered, SSI cable open, or clock line fault | High | Measure encoder supply voltage; check SSI cable continuity | Restore encoder power; replace SSI cable; verify clock/data wiring |
| Position value unstable or jumping | EMI on SSI lines, cable too long, or missing shield ground | High | Check cable length (SSI typically limited to ~100m); verify shield grounding | Use shielded twisted-pair cable; ensure single-point shield ground; reduce cable length |
| Latch function not triggering | Latch input wiring fault or incorrect trigger edge configuration | Medium | Verify latch input signal with oscilloscope or multimeter | Check wiring polarity; confirm trigger edge matches module configuration |
| All four channels reading zero | Module not receiving supply voltage or PLC not polling | High | Measure 12–48 VDC at module terminals; check PLC I/O mapping | Restore supply; verify PLC program is reading the correct input registers |
| Position scaling incorrect | Scale factor or preset value misconfigured | Medium | Compare raw encoder counts vs. scaled output in PLC | Recalculate scale factor; verify preset value matches mechanical reference |
AMCI 7264
Application Scenarios & Pain Points
Multi-axis web guiding. Converting and printing lines use multiple absolute encoders to monitor web position across several guide rollers. The 7264 reads all four encoders simultaneously, giving the PLC real-time position data for closed-loop web tension and alignment control. Without it, each encoder would require its own dedicated interface, multiplying cost and wiring complexity.
Cut-to-length registration. In flying shear and rotary knife applications, the latch input captures the exact encoder position when a registration mark sensor fires. This captured value is used to calculate the cut point with sub-millimeter accuracy. A missed latch trigger means a mis-cut and wasted material.
Packaging machine synchronization. Multi-station packaging machines need synchronized position feedback from several axes — infeed, forming, sealing, and discharge. The 7264 consolidates four SSI encoder inputs into a single module, reducing PLC slot usage and simplifying the I/O map.
