1764-LSP Product Overview
Is your MicroLogix 1500 system down due to a failed processor? The Allen-Bradley 1764-LSP is the base processor unit of the MicroLogix 1500 brick-style controller. It mounts on a 1764 power-supply/base I/O module to form a compact PLC for small machine and process control. This unit provides 7.6K word of user memory and communicates through an RS232 port using DH-485, DF1, Modbus, and ASCII protocols. It supports up to 512 expansion I/O points. The controller was discontinued on June 30, 2017. Rockwell recommends migrating to MicroLogix 1400 or CompactLogix 5370.
Key Technical Specifications
| Specification | Value |
|---|---|
| Part Number | 1764-LSP |
| Manufacturer | Allen-Bradley (Rockwell Automation) |
| Series | MicroLogix 1500 / Bulletin 1764 |
| Product Type | Processor / Controller (Base Unit) |
| User Memory | 7.6K word (Series B 12K / Series C 14K) |
| Communication Port | RS232 (DH-485, DF1, Modbus, ASCII) |
| Max Expansion I/O | Up to 512 points |
| Compatible Base Units | 1764-AWA, 1764-BWA, 1764-BXB |
| Memory Modules | 1764-MMx, 1764-RTC |
| Backup | RAM + 1764-BATM battery |
| Bus Current | ~380 mA |
| Trim Pots | 2 built-in |
| Mounting | DIN rail / panel |
| Lifecycle Status | Discontinued (2017-06-30) |
Upgrade and Replacement Guide
The 1764-LSP reached end-of-life on June 30, 2017. The entire MicroLogix 1500 platform was discontinued. For new installations, migrate to the MicroLogix 1400 or CompactLogix 5370. These platforms offer embedded Ethernet and higher performance. If you must maintain existing machinery, the 1764-LSP remains a functional replacement for failed units. Oil AutoTech supplies fast-dispatch spares for oil, gas, and industrial automation applications. We provide hands-on technical selection help to match your base unit and memory module needs. Contact Oil AutoTech today for pricing and availability.
Installation and Setup
Mount the 1764-LSP on a standard DIN rail or panel. It requires a compatible 1764 power-supply/base I/O module such as 1764-AWA, 1764-BWA, or 1764-BXB. Connect the RS232 port for programming and communication. Use RSLogix 500 or RSLogix Micro software. The controller holds program and data in volatile CMOS RAM. A 1764-BATM lithium battery backs up this memory. Optional 1764-MMx memory modules and 1764-RTC real-time clock are available. Always follow the manufacturer’s safety manual during installation.
Maintenance and Reliability
Inspect the 1764-BATM battery periodically. A low battery can cause program loss during power cycles. Check the RS232 connector for secure seating. Verify that the base unit and expansion I/O modules are firmly mounted. Keep the enclosure free of dust and moisture. The 1764-LSP has two built-in trim pots for analog adjustment. These may require periodic calibration. For discontinued units, stock spare processors to minimize downtime. Fast dispatch, worldwide delivery from Oil AutoTech keeps your line running.
Compatibility and Integration
The 1764-LSP works with 1764 series base units and 1762 expansion I/O modules. It supports DH-485, DF1, Modbus, and ASCII protocols over RS232. This allows integration with legacy control systems. For modern networks, consider a gateway or protocol converter. The instruction set is shared with SLC 500, easing migration. When upgrading to MicroLogix 1400 or CompactLogix 5370, verify wiring and panel space. Oil AutoTech provides technical selection help for these transitions.
Frequently Asked Questions
Q: Is the 1764-LSP still available?
A: No, it was discontinued on June 30, 2017. However, Oil AutoTech may have stock or can suggest a functional replacement.
Q: What memory modules work with the 1764-LSP?
A: It supports 1764-MMx memory modules and the 1764-RTC real-time clock.
Q: What is the maximum expansion I/O for this processor?
A: The 1764-LSP supports up to 512 expansion I/O points.
Q: What communication protocols does the RS232 port support?
A: DH-485, DF1, Modbus, and ASCII.
Q: What are the recommended replacements?
A: Rockwell recommends migrating to MicroLogix 1400 or CompactLogix 5370.
