1769-L35E — 1769 Series Controller, 1.5 MB Memory, EtherNet/IP

The 1769-L35E is a 1769-series modular programmable controller with 1.5 MB of user program and data memory and a built-in EtherNet/IP port. It runs full IEC 61131-3 programming languages in Studio 5000 / RSLogix 5000, supports motion control via analog outputs and network-based axis commands, and connects to the 1769 Compact I/O expansion bus for local I/O. The EtherNet/IP port handles both I/O scanning and peer-to-peer messaging without a separate communication module.

The L35E occupies a mid-tier position in the 1769 controller family — above the L31/L32 in memory and I/O capacity, below the L43/L45 in program complexity headroom. For machines and process cells with moderate I/O counts and straightforward control logic, the L35E's 1.5 MB memory provides comfortable headroom without the overhead of larger platforms.

Specifications

Parameter	Value
Part Number	1769-L35E
Series	1769 (Logix 5335E)
User Memory	1.5 MB (program + data combined)
Embedded Communication	EtherNet/IP (10/100 Mbps, RJ-45)
Local I/O Expansion	Up to 16 × 1769 Compact I/O modules
Remote I/O	Via EtherNet/IP (FLEX I/O, POINT I/O, other adapters)
Programming Languages	Ladder, Function Block, Structured Text, Sequential Function Chart
Tasks	Continuous, periodic, event (up to 32 total)
Motion Axes	2 (via analog or network-based axis commands)
Serial Ports	1 × RS-232 (DF1, ASCII, Modbus RTU)
Power Supply	External 24V DC (user-supplied)
Operating Temperature	0°C to 60°C
Standards	UL 508, CE, cUL, IEC 61131-3

Memory and Performance Context

The 1.5 MB combined memory pool holds both program code and data — tags, arrays, UDTs (user-defined data types), and produced/consumed tags. For typical machine control applications — interlocking, sequence logic, PID loops, HMI communication — 1.5 MB has substantial headroom. Memory becomes a constraint in programs with large recipe databases, extensive string handling, or high-density alarm tag structures.

The L35E supports up to 32 tasks total (continuous + periodic + event). Periodic tasks running at defined intervals are used for time-critical logic (PID loops, motion commands) that shouldn't be delayed by main scan variation. Event tasks fire on discrete triggers — I/O changes, consumed tag updates. Using periodic and event tasks correctly keeps time-sensitive loops predictable without over-sampling slow processes.

I/O Architecture and Network Connectivity

Up to 16 Compact I/O modules connect directly to the controller's right-side bus expansion — digital, analog, and specialty modules all supported. For field I/O beyond the local bus, the EtherNet/IP port manages remote I/O nodes (FLEX I/O with 1794-AENT, POINT I/O with 1734-AENT, remote 1769 chassis) over the same network connection used for HMI and peer communication. All remote I/O addressing is transparent in Studio 5000 — a module at a remote EtherNet/IP node is addressed and programmed the same way as a local module.

The RS-232 serial port handles legacy serial devices — HMIs over DF1, instruments and drives over Modbus RTU, and ASCII devices like barcode readers and printers. This port operates independently from the EtherNet/IP connection, so both can be active simultaneously.

FAQ

Q: Can the 1769-L35E manage CIP Motion servo axes over EtherNet/IP?

The L35E does not support CIP Motion (real-time servo axis control via EtherNet/IP). The 2 motion axes it supports use analog output or incremental command methods. For CIP Motion servo control, a higher-tier 1756-series controller with a 1756-M-series motion module is required.

Q: What is the maximum number of EtherNet/IP connections?

The L35E supports up to 256 EtherNet/IP connections. Each remote I/O adapter, HMI, drive with EtherNet/IP, and peer controller MSG connection consumes one connection. Large systems with many remote nodes should verify the connection count doesn't approach this limit.

Q: Does the controller require a separate EtherNet/IP communication module?

No. The EtherNet/IP port is built into the L35E controller module. No additional communication module is required for EtherNet/IP connectivity — a direct advantage over older 1769 controllers that required a separate 1769-L35E module for network access.

Q: Can the 1769-L35E connect to a DH-485 network?

Not natively. The RS-232 serial port on the L35E supports DF1, ASCII, and Modbus RTU, but not DH-485 directly. A 1761-NET-AIC (Advanced Interface Converter) connected to the serial port bridges DF1 to DH-485 for legacy network integration.

1769-L35E New In Box 1769L35E Processor Module