The integration of serial point-to-point connections into an EtherCAT network is handled efficiently by the Beckhoff EL6021 serial interface module, which provides a high-performance communication path for RS422 and RS485 devices. Operating as a single-channel communication terminal, this unit facilitates direct, isolated connection of serial equipment to the decentralized control architecture. By executing full-duplex or half-duplex transmission via balanced differential signaling, it guarantees robust data transfer even in environments subjected to severe electromagnetic interference. The device bypasses local address configurations entirely, allowing all functional variables and protocol behaviors to be parameterized through the master PLC system.
| Manufacturer | Beckhoff |
| Model / Article Number | EL6021 |
| Interface Standard | 1 x RS422 / RS485 |
| Data Transfer Channels | TxD and RxD, Full / Half Duplex |
| Data Transfer Rates | 2400 to 115,200 baud (Default: 9600 baud, 8 data bits, no parity, 1 stop bit) |
| Line Impedance | 120 ohm |
| Maximum Cable Length | Approximately 1000 m twisted pair |
| Power Supply Source | Via E-bus (no external power contacts) |
| Current Consumption (E-bus) | Typically 170 mA |
| Electrical Isolation | 500 V (E-bus / signal voltage) |
| Data Buffer | 864 bytes receive buffer, 128 bytes transmit buffer |
| Housing Dimensions (W x H x D) | 12 mm x 100 mm x 68 mm |
| Wire Cross-Section (Solid/Stranded) | 0.08 to 2.5 mm2 (AWG 28 to 14) |
| Wire Cross-Section (with Ferrule) | 0.14 to 1.5 mm2 (AWG 26 to 16) |
| Stripping Length | 8 to 9 mm |
| Operating Temperature | -25 to +60 degC |
| Storage Temperature | -40 to +85 degC |
| Relative Humidity | 95 percent, non-condensing |
| Approvals & Markings | CE, UL, ATEX, IECEx, cFMus |
| Device Weight | 55 g |
| Country of Origin | Germany |
| Shipping Weight (Calculated) | 0.15 kg |
| Package Dimensions (Calculated) | 150 mm x 120 mm x 45 mm |
| Terminal Pin | RS422 Mode Assignment | RS485 Mode Assignment |
|---|---|---|
| 1 | RxD+ (Receive Data Positive) | RxD/TxD-B (Data Positive) |
| 5 | RxD- (Receive Data Negative) | RxD/TxD-A (Data Negative) |
| 2 | TxD+ (Transmit Data Positive) | Not Used |
| 6 | TxD- (Transmit Data Negative) | Not Used |
| 3 | GND (Signal Ground) | GND (Signal Ground) |
| 7 | Shield | Shield |
| 4 / 8 | Shield Connection points | Shield Connection points |
The module offers identical software mapping to the ES6021 version. While the EL6021 features built-in spring-tension clamp terminations, the ES6021 provides pluggable terminal blocks for accelerated physical swaps. When replacing older revisions of this module in TwinCAT, check the XML device description version compatibility to ensure correct PDO (Process Data Object) structure mapping.
To prevent data loss over long-distance RS485 loops, the internal 120-ohm termination resistor must be active at the physical endpoints. A frequent engineering mistake is neglecting PLC cycle times; if the PLC scan rate is significantly slower than the serial incoming data block transmission time, the internal 864-byte receive buffer will overflow, causing buffer errors in the status word. Cycle your serial processing tasks concurrently with the data arrival rate.
Line termination for this module is configured strictly in software through the CoE (CAN over EtherCAT) directory index 0x8000. Ensure that the RS485/RS422 shielded cable is directly grounded to the DIN rail ground terminal. Unshielded serial lines running parallel to high-current variable frequency drive cabling can cause communication drops or corrupted checksum registers.
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Manufacturer: BECKHOFF
Product No.: EL6021
Country of origin:Germany
Product Type: EtherCAT Terminals
Payment: T/T, Western Union
Weight: 2000g
Dimensions: 150 mm x 120 mm x 45 mm
Shipping port: Xiamen
Warranty: 12 months
The integration of serial point-to-point connections into an EtherCAT network is handled efficiently by the Beckhoff EL6021 serial interface module, which provides a high-performance communication path for RS422 and RS485 devices. Operating as a single-channel communication terminal, this unit facilitates direct, isolated connection of serial equipment to the decentralized control architecture. By executing full-duplex or half-duplex transmission via balanced differential signaling, it guarantees robust data transfer even in environments subjected to severe electromagnetic interference. The device bypasses local address configurations entirely, allowing all functional variables and protocol behaviors to be parameterized through the master PLC system.
| Manufacturer | Beckhoff |
| Model / Article Number | EL6021 |
| Interface Standard | 1 x RS422 / RS485 |
| Data Transfer Channels | TxD and RxD, Full / Half Duplex |
| Data Transfer Rates | 2400 to 115,200 baud (Default: 9600 baud, 8 data bits, no parity, 1 stop bit) |
| Line Impedance | 120 ohm |
| Maximum Cable Length | Approximately 1000 m twisted pair |
| Power Supply Source | Via E-bus (no external power contacts) |
| Current Consumption (E-bus) | Typically 170 mA |
| Electrical Isolation | 500 V (E-bus / signal voltage) |
| Data Buffer | 864 bytes receive buffer, 128 bytes transmit buffer |
| Housing Dimensions (W x H x D) | 12 mm x 100 mm x 68 mm |
| Wire Cross-Section (Solid/Stranded) | 0.08 to 2.5 mm2 (AWG 28 to 14) |
| Wire Cross-Section (with Ferrule) | 0.14 to 1.5 mm2 (AWG 26 to 16) |
| Stripping Length | 8 to 9 mm |
| Operating Temperature | -25 to +60 degC |
| Storage Temperature | -40 to +85 degC |
| Relative Humidity | 95 percent, non-condensing |
| Approvals & Markings | CE, UL, ATEX, IECEx, cFMus |
| Device Weight | 55 g |
| Country of Origin | Germany |
| Shipping Weight (Calculated) | 0.15 kg |
| Package Dimensions (Calculated) | 150 mm x 120 mm x 45 mm |
| Terminal Pin | RS422 Mode Assignment | RS485 Mode Assignment |
|---|---|---|
| 1 | RxD+ (Receive Data Positive) | RxD/TxD-B (Data Positive) |
| 5 | RxD- (Receive Data Negative) | RxD/TxD-A (Data Negative) |
| 2 | TxD+ (Transmit Data Positive) | Not Used |
| 6 | TxD- (Transmit Data Negative) | Not Used |
| 3 | GND (Signal Ground) | GND (Signal Ground) |
| 7 | Shield | Shield |
| 4 / 8 | Shield Connection points | Shield Connection points |
The module offers identical software mapping to the ES6021 version. While the EL6021 features built-in spring-tension clamp terminations, the ES6021 provides pluggable terminal blocks for accelerated physical swaps. When replacing older revisions of this module in TwinCAT, check the XML device description version compatibility to ensure correct PDO (Process Data Object) structure mapping.
To prevent data loss over long-distance RS485 loops, the internal 120-ohm termination resistor must be active at the physical endpoints. A frequent engineering mistake is neglecting PLC cycle times; if the PLC scan rate is significantly slower than the serial incoming data block transmission time, the internal 864-byte receive buffer will overflow, causing buffer errors in the status word. Cycle your serial processing tasks concurrently with the data arrival rate.
Line termination for this module is configured strictly in software through the CoE (CAN over EtherCAT) directory index 0x8000. Ensure that the RS485/RS422 shielded cable is directly grounded to the DIN rail ground terminal. Unshielded serial lines running parallel to high-current variable frequency drive cabling can cause communication drops or corrupted checksum registers.
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Returns & Warranty
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| Country of origin |
Germany
|
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