Siemens 6ES5095-8FA01 S5-95F Redundant PLC

The 6ES5095-8FA01 operates as a single unit in S5-95F redundant configurations. This failsafe PLC executes safety-critical control tasks. It works together with a second identical unit for high availability.

Key Technical Specifications

Parameter	Value
Redundancy Type	Warm standby (1+1)
Program Memory	16 KB RAM (battery-backed)
Execution Speed	1 ms per 1K instructions
Data Memory	1 KB flags + 64 timers/counters
Supply Voltage	24V DC ±20%
Power Consumption	12 W typical
Digital I/O Capacity	256 channels max (failsafe)
Safety Level	Up to SIL 2
Communication Ports	2 x TTY (20 mA)
Unit Dimensions	25.0 cm x 14.0 cm x 5.5 cm
Weight	0.75 kg (1.65 lbs)
Component Count	192 discrete components
Energy Storage	3300 µF bulk capacitance
Operating Temperature	0°C to 60°C

Physical Dimensions and Component Layout

This unit measures 25.0 cm in length and 14.0 cm in width. Its total height reaches 5.5 cm including all connectors. 6ES5095-8FA01 weighs 0.75 kg for DIN rail mounting. You will find 192 discrete components on a six-layer PCB.

Moreover, the unit integrates a 3300 µF bulk capacitor bank. This bank stores energy for 50 ms during power interruptions. It also filters noise from the 24V DC supply rail.

Redundant Operation and Failover

Two identical units run the same user program simultaneously. The active unit controls the I/O while the standby unit synchronizes data. If the active unit fails, the standby takes over without process interruption. A dedicated fiber-optic cable handles the synchronization between units.

Failsafe Features and Diagnostics

The system includes dual processors with cross-checking of results. Each unit performs self-tests on memory and I/O circuits continuously. A built-in watchdog timer triggers a safe state if the CPU stops. LED indicators show active status, standby status, and fault conditions.

Communication and Programming

Two TTY ports connect to programming devices and operator panels. Each port uses a 20 mA current loop for noise immunity. You write safety programs using standard S5 ladder logic. The redundant system also supports online program changes without stopping production.

Typical Application Scenarios

You can deploy 6ES5095-8FA01 in burner management and emergency shutdown systems. It also works well for press control, chemical dosing, and conveyor safety. This PLC handles safety interlocks, light curtains, and two-hand controls. Its failsafe design meets SIL 2 requirements for industrial safety applications.