Field Engineer’s Notes (From the Trenches)
The “Gotcha” is Battery Replacement & Program Store.
Battery (IC698ACC701): The willlose its program if the battery dies AND power is lost. The “BAT LOW” LED illuminates ~30 days before failure, but it’s often ignored in PM rounds.
Rule: Replace the battery with power ON during a scheduled downtime. If you must replace with power OFF, have a laptop with the project file ready to download immediately upon power-up. A “No Config” fault on boot means the RAM cleared.
Store to Flash: The has Non-Volatile Flash (separate from the 10MB SRAM). If you want the CPU to auto-load the program after a total memory loss (dead batt + power cycle), you must perform a “Store Project to Flash” (Target -> Store in PME). This copies the SRAM image to Flash. On next cold start with dead battery, it will auto-load from Flash (takes ~30-60 sec). Without this, it waits for a download.
Ethernet IP Conflicts: The embedded port defaults to DHCP or a preset IP (often 192.168.1.10). If you have multiple RX7i racks on the same switch, ensure each has a unique IP. Duplicate IPs cause the “ARP Storm” that kills HMI connectivity to bothracks. Verify via
ipconfig /pingbefore leaving the site.
Real-World Applications
- Combined Cycle GT Startup Sequencer (9FA): A in the Gas Turbine core runs the Mark VI emulation logic (Speedtronic migration) plus the auxiliaries (Lube Oil, Seal Gas). The 10 MB memory holds the 4,000+ rungs of sequential logic and 2,000 symbolic variables. The embedded Ethernet links to the Woodward DSL and the Plant DCS (Modbus TCP) for start permissives.
- Municipal Water Treatment (Cl2/UV): Simplex RX7i with . Reads 64 discrete (valve positions, pump status), 16 analog (Cl2 residual, UV intensity, flow), controls 12 pump starters and chemical dosing pumps. The embedded Ethernet connects to a Wonderware InTouch HMI via SRTP. The 700 MHz scan time (6ms) ensures the Cl2 residual PID loop stays tight even during filter backwash surges.
High-Frequency Troubleshooting FAQ
Q: “RUN” LED is OFF, “FLT” is ON (Solid Red). “BAT LOW” was on last week. Program lost?
A: RAM Cleared (Battery Dead + Power Loss).
- If you performed “Store Project to Flash” previously: Power cycle the rack. The CPU should auto-load from Flash (Status LEDs cycle: MS blinking -> RUN comes on). Wait up to 90 seconds.
- If noFlash store was done: You must Download the project from Proficy Machine Edition. Connect via Ethernet (or Serial if configured). Target -> Connect -> Download.
- Prevention: Always “Store to Flash” after major logic changes and replace the battery (IC698ACC701) with power ON when BAT LOW appears.
Q: CPU is in RUN, but some I/O modules show “Not Responding” or “Config Mismatch”.
A: Hardware Detect Needed or Rack Power Issue.
- Open PME Hardware Config. Right-click the RX7i rack -> Detect Hardware. Does it see the modules you physically have? If it detects a mismatch (e.g., you have IC694MDL758 but config says IC694MDL759), update the config to match the physical hardware and re-download.
- Check the Power Supply Module (e.g., IC698PSA100) in Slot 0. Is the “PWR” LED Green? If the 5V backplane rail sags (overloaded or failing PS), the CPU runs but I/O modules drop off the bus. Measure 5V at the PS test points.
A: Yes, with caveats.
- The is designed for the RX7i (IC698CHS…) racks which have the PCI/VME64 hybrid backplane.
- It willphysically fit and operate in a Series 90-70 rack (IC697CHS771/791) provided the backplane firmware/revision supports the “PAC” protocol extensions (most late-model 90-70 racks with IC697CPU7xx upgrades do).
- Limitation: Some very old 90-70 I/O modules (pre-Rev C) may not be recognized. Run “Detect Hardware” to verify. For guaranteed compatibility in a 90-70 retrofit, the IC697CPU772 is the native choice, but the is commonly used for technology refresh to unify the platform with RX3i/RX7i programming tools (PME).
Please note: The listed price is not the actual final price. It is for reference only and is subject to appropriate negotiation based on current market conditions, quantity, and availability.
