Siemens 6AV6355-1AA47-7DC2 OP 77A

€ 995,00

SKU: 6AV6355-1AA47-7DC2 Category: HMI & Display Brand: Siemens

Description
Additional information

The Siemens 6AV6355-1AA47-7DC2 is an operator panel belonging to the SIMATIC HMI OP 77A series, manufactured by Siemens. It is a compact, key-operated operator panel designed for machine-level human-machine interface applications, providing a straightforward interface for process monitoring and control. The OP 77A is part of the SIMATIC HMI Basic Panels generation and is intended for use with Siemens SIMATIC S7 controllers via direct or network-based connections.

The OP 77A features a monochrome LCD display with a resolution of 160 x 80 pixels and a backlit screen for clear readability in various lighting conditions. It supports communication via MPI and PROFIBUS DP interfaces, enabling direct integration with S7-200, S7-300, and S7-400 PLCs. The panel is configured using WinCC flexible software and supports a defined number of tags, screens, and alarm messages suited to small-scale automation tasks. The unit operates on a 24 V DC supply and is rated IP65 on the front face for protection against dust and water ingress.

The OP 77A is commonly deployed in machine building, packaging machinery, conveyor systems, and small-scale process automation where a compact and cost-effective operator interface is required. Its robust front panel protection and compatibility with the SIMATIC controller family make it suitable for integration into control cabinets and machine panels across manufacturing and industrial environments. The panel is particularly well suited to OEM machine builders requiring a standardized HMI solution within the Siemens automation ecosystem.

Technical Specifications

Display Type	Monochrome LCD with backlight
Display Resolution	160 x 80 pixels
Operating Voltage	24 V DC
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
Configuration Software	WinCC flexible 2008 or higher
Mounting	Panel mounting
Series	SIMATIC HMI OP 77A
Certifications	CE, UL, cULus

Common Error Codes and System Events

Event ID: 1000: System startup completed successfully. The HMI panel has finished booting and is ready for operation.
No action required. This is an informational event confirming normal startup.
Event ID: 10000: Communication error detected. The panel cannot establish or maintain communication with the configured PLC.
Check MPI or PROFIBUS DP cable connections and termination resistors. Verify PLC address settings and ensure the PLC is powered and running.
Event ID: 10001: Connection to PLC interrupted during operation.
Inspect communication cables for damage or loose connections. Verify network configuration and PLC operational status. Restart the panel if the connection is not re-established automatically.
Event ID: 20000: Tag read error. The panel is unable to read a configured tag from the PLC.
Verify the tag address in the WinCC flexible project matches the actual PLC data block or memory address. Check PLC program for address changes.
Event ID: 40000: Project download error. A project transfer to the panel has failed.
Check the transfer cable or network connection between the engineering PC and the panel. Ensure WinCC flexible version compatibility and sufficient panel memory.
Event ID: 50000: Alarm buffer overflow. The number of pending alarms has exceeded the panel buffer capacity.
Acknowledge and clear existing alarms. Review the alarm configuration in WinCC flexible to reduce unnecessary alarm generation.
Event ID: 70000: Operating system error. An internal system fault has been detected on the HMI panel.
Perform a panel restart. If the fault persists, reload the HMI project via WinCC flexible or consider restoring the panel firmware.

Frequently Asked Questions

Which PLCs are compatible with the OP 77A panel?

The OP 77A is compatible with Siemens SIMATIC S7-200, S7-300, and S7-400 PLCs via MPI or PROFIBUS DP communication interfaces.

What software is used to configure the OP 77A?

The OP 77A is configured using Siemens WinCC flexible 2008 or a compatible version. Projects are transferred to the panel via MPI, PROFIBUS DP, or a direct serial connection.

What is the supply voltage for the 6AV6355-1AA47-7DC2?

The panel operates on a 24 V DC supply voltage.

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

The front panel of the OP 77A is rated IP65, providing protection against dust ingress and low-pressure water jets.

Can the OP 77A display color graphics?

No, the OP 77A uses a monochrome LCD display and does not support color graphics. It is suited for text-based and simple graphical operator interfaces.

Troubleshooting

Display remains blank after power on

Measure the 24 V DC supply voltage at the power connector on the rear of the panel. Check for blown internal fuses or wiring faults in the control cabinet.

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

Panel shows communication error and cannot connect to PLC

Verify MPI or PROFIBUS DP cable integrity and correct termination at both ends of the network. Check that the PLC address configured in the WinCC flexible project matches the actual PLC node address.

Replace or reseat communication cables. Correct address settings in the WinCC flexible project and re-download the project to the panel. Ensure termination resistors are correctly placed at network endpoints.

Project transfer from WinCC flexible fails

Check the physical connection between the engineering PC and the panel. Confirm that the panel is in transfer mode and that the correct communication port and transfer settings are selected in WinCC flexible.

Set the panel to transfer mode via the panel start screen. Verify COM port or network settings in WinCC flexible. Retry the transfer after confirming compatibility between the project version and the panel firmware.

Alarms are not displayed on the panel

Check the alarm configuration in the WinCC flexible project to confirm alarm tags are correctly mapped to PLC addresses. Verify that the PLC is writing the correct bit or value to trigger the alarm.

Correct tag address mappings in the WinCC flexible project and re-download to the panel. Test alarm triggering by manually setting the relevant PLC bit and observing the panel response.

Panel display is readable but keys are unresponsive

Inspect the keypad membrane for physical damage or contamination. Check whether the panel is in a locked or protected operating mode that restricts key input.

Clean the keypad area if contamination is present. Disable any operator input protection configured in the WinCC flexible project. If keys remain unresponsive after these steps, the keypad membrane assembly may require replacement.

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