Schneider Electric / Eurotherm 818S Temperature Controller / Programmer

The Schneider Electric Eurotherm 818S is a 1/4 DIN single-loop PID temperature controller and programmer built for precision process control in industrial environments. This panel-mount unit combines a dual display for concurrent viewing of process variables and setpoints with self-tuning and adaptive tuning capabilities. The 818S executes ramp-to-setpoint programming, offering software-configurable control through modular plug-in architecture suited to diverse thermal management requirements.

Technical Specifications

Form Factor & Mounting

• 1/4 DIN panel mount


• 96 mm (W) × 96 mm (H) × 219 mm (D) including terminal cover


• IP54 panel sealing with supplied gasket Control & Display


• Single-loop PID control with dual display


• Self-tuning and adaptive tuning


• Ramp-to-setpoint programmer function Power & Electrical


• Supply: 85–264 VAC (50/60 Hz) or optional 17–40 VAC / 20–40 VDC


• Power consumption: 8.5–10 W


• Fusing: 2 A (T) @ 85–264 V AC; 3.15 A (T) @ 17–40 V; 2 A (T) relay outputs; 1 A (T) triac outputs Outputs


• Control output: Isolated 4–20 mA (reverse acting)


• Relay output: max 264 VAC, 2 A resistive


• Triac output: max 264 VAC, 1 A resistive


• Alarm outputs: up to 2 configurable alarms


• Leakage current: <2 mA through suppression components Inputs


• Thermocouple input with 31 linearization options


• DC isolated input: 0–20 mA or 0–10 V


• Analog comms DC: 0–20 mA (600 Ω max) or 0–10 V (5 kΩ min)


• DC isolated output: 0–20 mA or 0–10 V; also 0–20 mA or −5–10 V


• Logic input (non-isolated): 4 V non-active, volt-free contact capable


• Digital inputs 1 & 2: configuration-dependent


• Isolated potentiometer supply: 10 V, 1 mA

Key Features

• Dual-display architecture for simultaneous parameter monitoring


• Modular software configuration with plug-in module support


• Self-tuning and adaptive control algorithms


• Multiple input linearizations for thermocouple and linear sources


• Isolated 4–20 mA control output with reverse acting logic


• Configurable alarm outputs for process monitoring

Typical Applications Process heating control, thermal chamber management, industrial furnace regulation, and temperature-dependent manufacturing workflows requiring precise closed-loop regulation and programmable ramp profiles.

Compatibility & Integration The 818S integrates within the Eurotherm 818 Series ecosystem. Plug-in module configuration enables adaptation to specific control topologies, input sensor types, and output requirements across heat, cool, and motorized valve applications.