Siemens 6AV6355-1AA47-7DA1 OP 77A

€ 1.338,50

SKU: 6AV6355-1AA47-7DA1 Category: HMI & Display Brand: Siemens

Description
Additional information

The Siemens 6AV6355-1AA47-7DA1 is an operator panel belonging to the SIMATIC HMI OP 77A series, designed for machine-level human-machine interface applications. This compact panel provides a key-based interface for process visualization and operator control in industrial automation environments. It is part of Siemens' SIMATIC HMI portfolio and is intended for use with SIMATIC S7 and other compatible controllers.

The OP 77A features a monochrome LCD display with a resolution of 160 x 80 pixels, providing clear readout of process values, alarms, and status messages. The panel supports MPI and PROFIBUS DP communication interfaces, enabling direct integration with Siemens S7-200, S7-300, and S7-400 PLCs. It includes function keys and system keys for operator input, and is configured using the WinCC flexible engineering software. The unit operates on a 24 V DC supply and is rated for industrial environments with an IP65 protection rating on the front panel.

The OP 77A is commonly deployed in machine building, conveyor systems, packaging machinery, and process automation where a compact, cost-effective operator interface is required. Its rugged construction and compatibility with the SIMATIC controller family make it suitable for integration into existing Siemens automation architectures. The panel is well-suited for applications requiring alarm display, recipe management, and basic process value visualization at the machine level.

Technical Specifications

Display Type	Monochrome LCD
Display Resolution	160 x 80 pixels
Input Voltage	24 V DC
Power Consumption	Max. 4.5 W
Communication Interface	MPI, PROFIBUS DP
IP Rating (Front)	IP65
IP Rating (Rear)	IP20
Operating Temperature	0 °C to +50 °C
Storage Temperature	-20 °C to +60 °C
Relative Humidity	10% to 90% (non-condensing)
Mounting	Panel mounting
Engineering Software	WinCC flexible 2005 or higher
Certifications	CE, UL, cULus
Series	SIMATIC HMI OP 77A

Common Error Codes & System Events

Event ID: 10000: Communication error between the HMI panel and the connected PLC. The connection to the controller has been interrupted or cannot be established.
Check MPI or PROFIBUS DP cable connections and terminating resistors. Verify the PLC address settings and ensure the PLC is in RUN mode. Check the communication parameters configured in WinCC flexible.
Event ID: 10001: Connection timeout to the configured PLC. The panel did not receive a response from the controller within the expected time.
Verify network cabling and connector integrity. Confirm the PLC station address matches the project configuration. Restart both the panel and the PLC if the issue persists.
Event ID: 20000: Tag read error. The panel is unable to read a configured process tag from the PLC.
Check that the tag address in WinCC flexible matches the actual PLC data block or memory address. Verify the PLC program contains the referenced data area.
Event ID: 20001: Tag write error. The panel is unable to write a value to the configured PLC tag.
Confirm the PLC memory area is not write-protected. Verify the tag address configuration in WinCC flexible and ensure the PLC is in a state that accepts write commands.
Event ID: 40000: Project download error. A project transfer from the engineering PC to the panel has failed.
Check the transfer cable connection and ensure the panel is in transfer mode. Verify that the WinCC flexible project is compatible with the OP 77A firmware version. Retry the download.
Event ID: 50000: System memory low. The panel's available memory for runtime operation is critically low.
Reduce the number of configured screens, tags, or alarm messages in the WinCC flexible project. Reload the project after optimization.
Event ID: 60000: Firmware update error. An error occurred during a firmware update procedure on the panel.
Ensure the correct firmware version for the OP 77A is used. Repeat the update procedure using the ProSave tool and verify the connection between the PC and the panel.
Event ID: 70000: Alarm buffer overflow. The number of pending alarms has exceeded the panel's alarm buffer capacity.
Acknowledge and clear existing alarms on the panel. Review the alarm configuration in WinCC flexible to reduce unnecessary alarm triggers or increase acknowledgement frequency.

Frequently Asked Questions

Which communication interfaces does the OP 77A support?

The OP 77A supports MPI and PROFIBUS DP interfaces, allowing direct connection to Siemens S7-200, S7-300, and S7-400 PLCs without an additional communication module.

Which engineering software is required to configure the OP 77A?

The OP 77A is configured using Siemens WinCC flexible 2005 or a later version. Projects are downloaded to the panel via the MPI interface or a dedicated transfer cable.

What is the supply voltage for the 6AV6355-1AA47-7DA1?

The panel operates on a 24 V DC supply voltage, which is standard for SIMATIC HMI devices in industrial cabinet installations.

What is the front panel protection rating of the OP 77A?

The front panel of the OP 77A is rated IP65, making it resistant to dust ingress and low-pressure water jets, suitable for most industrial machine environments.

Can the OP 77A be used with third-party PLCs?

The OP 77A is primarily designed for use with Siemens SIMATIC S7 controllers via MPI or PROFIBUS DP. Connectivity to third-party PLCs is limited and depends on PROFIBUS DP compatibility of the third-party device.

Troubleshooting

Display remains blank after power on

Check the 24 V DC supply voltage at the panel's power connector. Verify that the supply is within the specified range and that the connector is firmly seated.

Restore correct 24 V DC supply. If the supply is confirmed correct and the display remains blank, the internal power supply or backlight may be faulty and the unit should be sent for repair or replacement.

Panel shows 'No connection to PLC' message on startup

Verify the MPI or PROFIBUS DP cable is correctly connected to both the panel and the PLC. Check that the bus termination resistors are correctly placed at both ends of the network.

Correct any wiring faults and ensure proper bus termination. Confirm that the PLC station address in the WinCC flexible project matches the actual PLC configuration. Restart the panel after corrections.

Project download from PC to panel fails

Ensure the panel is set to transfer mode by pressing the appropriate key combination on startup. Verify the transfer cable type and PC COM port settings are correct.

Place the panel in transfer mode, select the correct interface in WinCC flexible transfer settings, and retry the download. If using USB-to-serial adapters, try a different adapter or a direct serial connection.

Operator keys are unresponsive or behave incorrectly

Check whether the issue is consistent across all keys or limited to specific ones. Inspect the keypad membrane for physical damage or contamination.

Clean the keypad area if contamination is present. If specific keys are permanently unresponsive, the keypad membrane may require replacement. Contact a qualified repair service for internal keypad replacement.

Alarms are not displayed or acknowledged correctly

Review the alarm configuration in the WinCC flexible project to confirm that alarm tags are correctly mapped to PLC addresses. Check that the PLC is setting the alarm bits as expected.

Correct any tag address mismatches in the WinCC flexible project and reload the project to the panel. Verify PLC logic is correctly triggering alarm bits and that acknowledgement handling is configured properly.

Condition	Repair, Used, Refurbished, New in box (sealed)