Beckhoff EL1904 EtherCAT Terminal

The Beckhoff EL1904 is a TwinSAFE digital input terminal with 4 fail-safe channels for sensors using potential-free contacts at 24 V DC. It enables reliable signal acquisition for safety-relevant applications and communicates via the Safety over EtherCAT (FSoE) protocol. Designed to meet the highest functional safety requirements, it conforms to SIL 3 (IEC 61508) and PL e (EN ISO 13849-1).

With support for 1-channel and 2-channel evaluation, cross-circuit detection, and configurable channel testing, the EL1904 delivers flexible, fail-safe input integration into TwinSAFE systems. Safety parameters are managed externally by a TwinSAFE Logic-capable controller, allowing for simplified servicing and component replacement.

Technical Specifications

Manufacturer: Beckhoff
Part Number: EL1904 Beckhoff
Product Type: Safety Digital Input Terminal
Input Channels: 4 (safe inputs)
Connection Technology: 1-/2-wire
Input Type: Potential-free contact (24 V DC)
Protocol: TwinSAFE / Safety over EtherCAT (FSoE)
Response Time: Typ. 4 ms (read input / write to E-bus)
Fault Response Time: ≤ Watchdog time (parameterizable)
Safety Evaluation: 1-channel or 2-channel configurable
Cross-Circuit Detection: Yes
Channel Testing: Individually activatable
Safety Parameter Storage: External via TwinSAFE Logic

Electrical & Power

Power Supply: Via E-bus
Current Consumption (E-bus): Typ. 200 mA
Current Consumption (Power Contacts): See documentation
Electrical Isolation: 500 V (E-bus/field potential)
Protection Rating: IP20

Mechanical Specifications

Dimensions (W x H x D): 12 mm x 100 mm x 68 mm
Housing Type: EL-12-8pin
Material: Polycarbonate
Mounting: 35 mm DIN rail (EN 60715)
Side-by-Side Mounting: Double slot and key system
Wiring Type:
– Solid: 0.08–2.5 mm²
– Stranded: 0.08–2.5 mm²
– Ferrule: 0.14–1.5 mm²
AWG Range: AWG28–14 (solid/stranded), AWG26–16 (ferrule)
Stripping Length: 8–9 mm
Max Current Load (Power Contacts): 10 A

Environmental Conditions

Operating Temperature: -25°C to +60°C
Storage Temperature: -40°C to +85°C
Relative Humidity: 95% (non-condensing)
Installation Position: Horizontal
Vibration/Shock Resistance: EN 60068-2-6 / EN 60068-2-27

Approvals & Compliance

Safety Standards:
– EN ISO 13849-1:2008 (Cat. 4, PL e)
– EN 61508:2010 (SIL 3)
Certifications: CE, UL, CCC, ATEX, IECEx
ATEX Marking: II 3 G Ex ec IIC T4 Gc
IECEx Marking: Ex ec IIC T4 Gc

Key Features

✅ 4 Fail-Safe Inputs: Suitable for SIL 3 / PL e safety circuits.

✅ Flexible Evaluation: 1- or 2-channel logic with configurable channel tests.

✅ Cross-Circuit Detection: Ensures signal integrity and safety.

✅ Service Friendly: Safety parameters are stored in the controller, not the device.

✅ TwinSAFE Integration: Seamless with other FSoE-capable components.

📦 Buy Beckhoff EL1904 TwinSAFE Digital Input Terminal – UK Stock, Competitive Prices

At Drive Outlet Megastore we offer unbeatable Beckhoff EL1904 prices.

Whether you’re upgrading safety-critical systems or building a new TwinSAFE infrastructure, the EL1904 ensures certified protection and diagnostic transparency.

Get in touch now to request a quote or place your order today.