Siemens 6ES5376-0AA21 Memory Module

This memory module stores user programs for SIMATIC S5 central controllers. It holds your automation logic permanently without needing a backup battery. You can insert this unit into any S5 CPU memory slot.

Technical Specifications

Parameter	Details
Brand	Siemens
Model	Siemens 6ES5376-0AA21
Category	Memory Module (SIMATIC S5 Series)
Dimensions (H x W x D)	35 mm x 90 mm x 15 mm
Weight	0.04 kg
Memory Type	EPROM (Erasable Programmable Read-Only Memory)
Storage Capacity	4 KB
Number of Components	2 EPROM chips + 1 PCB assembly
Interface Type	40-pin edge connector
Access Time	250 ns (typical)
Data Retention	Over 10 years without any power source
Write Cycles	100 times (erase with UV light required)
Erasure Method	Ultraviolet light (254 nm, 15 minutes)
Operating Voltage	5 V DC ±5%
Current Draw	80 mA (read mode) / 1 mA (standby)
Built-in Energy Storage	None (non-volatile EPROM technology)
Protection Features	Plastic cover over quartz erasure window
Operating Temperature	0°C to 70°C
Humidity Tolerance	10% to 90% non-condensing

Detailed Feature Overview

This module uses two EPROM chips for 4 KB of total storage. It retains your program for over 10 years without any battery. Consequently, you never worry about data loss during long power outages.

The access time reaches 250 ns for fast program execution. You can read the memory contents instantly after power-up. A quartz window on top allows UV light to erase the chips for reprogramming.

You will find a protective sticker covering the quartz erasure window. Remove this sticker only when you need to erase the module. Exposure to sunlight or fluorescent light can gradually corrupt the data.

Installation and Compatibility

Siemens 6ES5376-0AA21 fits S5 CPUs like 6ES5944 or 6ES5130. Insert the module into the designated memory slot with correct orientation. Use a UV eraser lamp for 15 minutes to clear existing data.