Implementing 3-Switch XOR Ladder Logic with Internal Bit
Implement a 3-SPST switch XOR light circuit in LogixPro or RSLogix 500 using an internal relay bit. Includes truth tables, boolean equations, and verified.
Integrating directly into high-speed automation architectures, the Beckhoff EL2124 provides fast, precise digital control over four independent 5 V DC channels. Engineered for rapid switching dynamics, this EtherCAT Terminal utilizes a CMOS push-pull output design capable of actively sourcing and sinking up to 20 mA per channel. Ideal for interfacing with low-voltage logic levels, optocouplers, and high-frequency digital receivers, the module features sub-microsecond propagation delays to ensure real-time response times within critical control loops.
| Specification Parameter | Technical Value |
|---|---|
| Manufacturer | Beckhoff |
| Model Series | EtherCAT Terminal (EL Series) |
| Number of Outputs | 4 channels |
| Nominal Output Voltage | 5 V DC |
| Output Driver Type | CMOS push-pull (source/sink) |
| Maximum Output Current | +/- 20 mA per channel (short-circuit proof) |
| Switching Propagation Delay | TON < 1 us, TOFF < 1 us |
| Current Consumption (E-bus) | Typically 130 mA |
| Current Consumption (Power Contacts) | Typically 12 mA + load |
| Electrical Isolation | 500 V (E-bus to field potential) |
| Load Type Compatibility | Ohmic, lamp load |
| Operating Temperature | 0 degC to +55 degC |
| Storage Temperature | -25 degC to +85 degC |
| Relative Humidity | 95%, non-condensing |
| Connection Technology | 2-wire or 3-wire direct connection |
| Connection Cross-Section (Solid/Stranded) | 0.08 mm2 to 2.5 mm2 (AWG 28 to 14) |
| Connection Cross-Section (Ferrule) | 0.14 mm2 to 1.5 mm2 (AWG 26 to 16) |
| Ingress Protection Rating | IP20 (conforms to EN 60529) |
| Ex Marking / Hazardous Location | II 3 G Ex nA IIC T4 Gc |
| Country of Origin | Germany |
| Physical Dimensions | Width: 12 mm Height: 100 mm Depth: 68 mm |
| Shipping Weight (Calculated) | 0.15 kg |
| Package Dimensions (Calculated) | 150 mm x 120 mm x 40 mm |
The terminal integrates directly into standard TwinCAT 2.x and 3.x system structures. While utilizing the same physical footprint as typical 24 V DC terminals, the unit requires dedicated 5 V DC logic-side distribution. Ensure that any downstream configurations do not inadvertently route field voltages above the rated 5 V threshold to this module.
Because this module utilizes standard CMOS push-pull outputs, it actively drives the signaling line both high and low. Avoid connecting multiple output channels in parallel to boost current driving capabilities, as minor switching delays between channels can induce transient short circuits. Additionally, verify the E-bus power supply margins of your coupler segment; a single terminal consumes 130 mA typical E-bus current.
For signal transmission distances exceeding 3 meters, shielded twisted-pair cabling is strongly recommended to minimize environmental electromagnetic interference. Ground the cable shield securely at the control panel boundary plate to isolate high-speed CMOS switching channels from structural floor noise.
CRITICAL WARNING:
De-energize the entire control system and disconnect all field power contacts before installing, servicing, or extracting any EtherCAT terminal. Failure to do so can result in electrical arcing, destruction of sensitive CMOS drivers, or transmission faults across the adjacent E-bus.
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Integrating directly into high-speed automation architectures, the Beckhoff EL2124 provides fast, precise digital control over four independent 5 V DC channels. Engineered for rapid switching dynamics, this EtherCAT Terminal utilizes a CMOS push-pull output design capable of actively sourcing and sinking up to 20 mA per channel. Ideal for interfacing with low-voltage logic levels, optocouplers, and high-frequency digital receivers, the module features sub-microsecond propagation delays to ensure real-time response times within critical control loops.
| Specification Parameter | Technical Value |
|---|---|
| Manufacturer | Beckhoff |
| Model Series | EtherCAT Terminal (EL Series) |
| Number of Outputs | 4 channels |
| Nominal Output Voltage | 5 V DC |
| Output Driver Type | CMOS push-pull (source/sink) |
| Maximum Output Current | +/- 20 mA per channel (short-circuit proof) |
| Switching Propagation Delay | TON < 1 us, TOFF < 1 us |
| Current Consumption (E-bus) | Typically 130 mA |
| Current Consumption (Power Contacts) | Typically 12 mA + load |
| Electrical Isolation | 500 V (E-bus to field potential) |
| Load Type Compatibility | Ohmic, lamp load |
| Operating Temperature | 0 degC to +55 degC |
| Storage Temperature | -25 degC to +85 degC |
| Relative Humidity | 95%, non-condensing |
| Connection Technology | 2-wire or 3-wire direct connection |
| Connection Cross-Section (Solid/Stranded) | 0.08 mm2 to 2.5 mm2 (AWG 28 to 14) |
| Connection Cross-Section (Ferrule) | 0.14 mm2 to 1.5 mm2 (AWG 26 to 16) |
| Ingress Protection Rating | IP20 (conforms to EN 60529) |
| Ex Marking / Hazardous Location | II 3 G Ex nA IIC T4 Gc |
| Country of Origin | Germany |
| Physical Dimensions | Width: 12 mm Height: 100 mm Depth: 68 mm |
| Shipping Weight (Calculated) | 0.15 kg |
| Package Dimensions (Calculated) | 150 mm x 120 mm x 40 mm |
The terminal integrates directly into standard TwinCAT 2.x and 3.x system structures. While utilizing the same physical footprint as typical 24 V DC terminals, the unit requires dedicated 5 V DC logic-side distribution. Ensure that any downstream configurations do not inadvertently route field voltages above the rated 5 V threshold to this module.
Because this module utilizes standard CMOS push-pull outputs, it actively drives the signaling line both high and low. Avoid connecting multiple output channels in parallel to boost current driving capabilities, as minor switching delays between channels can induce transient short circuits. Additionally, verify the E-bus power supply margins of your coupler segment; a single terminal consumes 130 mA typical E-bus current.
For signal transmission distances exceeding 3 meters, shielded twisted-pair cabling is strongly recommended to minimize environmental electromagnetic interference. Ground the cable shield securely at the control panel boundary plate to isolate high-speed CMOS switching channels from structural floor noise.
CRITICAL WARNING:
De-energize the entire control system and disconnect all field power contacts before installing, servicing, or extracting any EtherCAT terminal. Failure to do so can result in electrical arcing, destruction of sensitive CMOS drivers, or transmission faults across the adjacent E-bus.
Global Express Shipping
Returns & Warranty
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| Country of origin |
Germany
|