I/O & fieldbus

EtherCAT terminals, box modules, and gateways for signals, safety, and field connectivity.

Official product overview →

Beckhoff I/O is built around EtherCAT speed and topology flexibility: cabinet terminals, field-mount boxes, and couplers for almost every signal type.

EtherCAT terminal modules

12 mm DIN-rail slices: digital, analog, temperature, specialty, and motion interfaces.

  • Digital inputs/outputs with configurable channels.
  • Analog voltage/current, thermocouple, RTD, and more.
  • Fast sampling, timestamps, and diagnostics with TwinCAT.

EtherCAT box modules (field / IP67)

Machine-mounted modules with molded connectors for harsh environments.

  • Shortens cable runs from sensors/actuators to the cabinet.
  • Common in conveyors, machine tools, and washdown areas.

Couplers, junctions, and safety I/O

Couplers connect segments; safety I/O integrates with TwinCAT Safety (STO/SIL/PL as applicable).

  • EtherCAT topology: line, tree, redundancy—design-dependent.
  • Safety configuration must follow applicable standards and validation.
  • Other fieldbus gateways are listed in the catalog.

Naming hints (illustrative)

PrefixMeaning (approx.)
ELEtherCAT terminal (electronics)
EPEtherCAT box (field)
EKEtherCAT coupler

Exact naming rules live in official catalogs; this table is for orientation only.

Appendix: excerpt order codes & typical configuration

Thousands of EL/EP/EK variants exist; rows below are common examples. Trailing order-code suffixes may encode connector color or options—always read the data sheet.

Models & ordering guide → infosys.beckhoff.com

Not exhaustive. Use Beckhoff Information System or the China product search for the complete live list.

EL — Digital input (24 V DC typical)
ModelKey specsTypical configuration / notes
EL10088×DI3 ms filter; 24 V
EL101816×DI3 ms; high density
EL102424×DI3 ms
EL10344×DI10 µs filter option family
EL10888×DINegative switching / NAMUR context per DS
EL10944×DI4× digital input
EL11044×DI120/230 V AC family (verify voltage class)
EL11244×DIWith diagnostics
EL11344×DICompare DS for threshold
EL11544×DICompare DS
EL126216×DI1 µs timestamp
EL12644×DITimestamp / oversampling family
EL18088×DI24 V; HD slice
EL180916×DI24 V; HD
EL181916×DI24 V; HD + diagnostics
EL18598×DI+8×DOMixed HD slice
EL188916×DI24 V; HD
EL19188×safe DISafety input—TwinCAT Safety
EL10044×DI4-channel; compare filter vs EL1008
EL101212×DI12 DI compact
EL10224×DI2× 3-wire + 2× 2-wire configurable
EL17022×DI120 V AC / 230 V AC (verify DS)
EL17422×DIAC input family
EL19044×safe DISafety digital input
EL19344×safe DISafety input variant
EL — Digital output
ModelKey specsTypical configuration / notes
EL20088×DO24 V; 0.5 A per channel typical
EL20144×DORelay / compare DS
EL20244×DO24 V; 2 A family
EL20344×DO24 V
EL20444×DO24 V
EL20888×DO24 V
EL26222×relayNO contact
EL26344×relayCompare contact rating
EL28088×DO24 V; 0.5 A
EL280916×DO24 V; 0.5 A; HD
EL287216×DO24 V; HD slice
EL288916×DO24 V; HD
EL29044×safe DOSafety output—TwinCAT Safety
EL20044×DO24 V; 0.5 A typical
EL201212×DO24 V outputs
EL20222×DO2-channel DO
EL27988×DOOV (sink) switching family
EL28878×DOCompare output type per DS
EL27944×DOSpecial switching—check DS
EL — Analog input
ModelKey specsTypical configuration / notes
EL30011×AI±10 V differential
EL30022×AI±10 V
EL30044×AI±10 V
EL30111×AI0–20 mA / 4–20 mA
EL30122×AICurrent
EL30144×AICurrent
EL30244×AI±10 V / 0–10 V per DS
EL30411×AI0–20 mA single-ended
EL30422×AICurrent
EL30444×AICurrent
EL30511×AI±10 V / 0–10 V
EL30522×AIVoltage
EL30544×AIVoltage
EL30611×AI±30 V / 0–10 V class
EL31011×AI±10 V differential fast
EL31111×AI±20 mA / 0–20 mA
EL31411×AI±10 V oversampling family
EL33144×TCThermocouple
EL33188×TCThermocouple
EL33511×bridgeStrain gauge / resistor bridge
EL33611×bridge6-wire strain / precision
EL33622×bridgeDual measuring bridge
EL3689HD analogHigh-density analog input slice
EL37511×AIMeasuring range per datasheet
EL37733×AIPower monitoring / 3-phase (verify)
EL — RTD / resistance temperature (EL32xx)
ModelKey specsTypical configuration / notes
EL32011×RTDPt100 / Ni sensor; 2/3/4-wire per order
EL32022×RTDRTD inputs
EL32044×RTDMulti-channel RTD
EL32144×RTDHigh precision family
EL32244×RTDCompare accuracy class
EL3255IEPE / meas.Measurement terminal (verify DS)
EL — Analog output
ModelKey specsTypical configuration / notes
EL40011×AO0–10 V
EL40022×AO±10 V
EL40044×AO0–10 V
EL40111×AO0–20 mA
EL40211×AO4–20 mA
EL40311×AO±10 V
EL40322×AO0–10 V
EL40344×AO0–10 V
EL41011×AO±10 V fast
EL41111×AO0–20 mA
EL41211×AO±10 V fast output
EL41422×AO±10 V / 0–10 V
EL47322×AOIsolated analog out
EL — Position / encoder (EL5xxx, excerpt)
ModelKey specsTypical configuration / notes
EL5001SSISSI encoder interface
EL5021SinCos 1 VppAnalog incremental encoder
EL5032EnDat 2.2Absolute encoder bus
EL5042BiSS CBiSS encoder interface
EL5101Incremental24 V HTL/TTL family
EL5151IncrementalCompare voltage class
EL — Communication / system (examples)
ModelKey specsTypical configuration / notes
EL6001RS232Serial port
EL6021RS485Serial
EL6631PROFINET deviceGateway slice
EL6692EtherNet/IPCompare license/diagnosis
EL6695Time syncPTP / per DS
EL9010End terminalBus end plate
EL9410Power supplyE-bus refresh
EL6224IO-Link masterPorts / class per DS
EL6652EtherCAT bridgeCompare topology use-case
EL6731PROFIBUS masterGateway terminal
EL6751CANopen masterGateway
EL9210Power supply24 V IN / system supply
EL9560Power supplyCompare voltage / current
ES / EM — Naming vs EL
PrefixKey specsTypical configuration / notes
ELEtherCAT terminalFull electronics in 12 mm slice; most common for TwinCAT
ESStandard terminalLegacy / bus-coupler systems; pair with EK coupler for fieldbus
EMMeasurement / specialtyOften EL-like but measurement-focused families—check Infosys
EK — EtherCAT couplers
ModelKey specsTypical configuration / notes
EK1100EtherCAT couplerStandard RJ45
EK1110ExtensionSegment extension
EK11222-port junctionBranch / topology
EK1501CouplerFiber-optic variant family
EK1130ExtensionDistance / copper extension per DS
EK1521Fiber couplerMultimode fiber link
EK1541FiberCompare fiber type
EP — EtherCAT box (field)
ModelKey specsTypical configuration / notes
EP10088×DIM8/M12 connectors per ordering
EP101816×DIHigh density
EP20088×DO24 V outputs
EP20288×DOCompare current
EP31744×AIAnalog box
EP3744TCTemperature box
EP233916×DI+16×DOCompact mixed I/O box
EP43744×AI±10 V / 0–10 V field
EP6224IO-LinkIP67 IO-Link master

Specifications vary by order code. Verify with Beckhoff documentation before ordering.