Siemens 6AV6355-1AA31-8DL7 OP 77A

€ 3.495,00

SKU: 6AV6355-1AA31-8DL7 Category: HMI & Display Brand: Siemens

Description
Additional information

The Siemens 6AV6355-1AA31-8DL7 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 text-based visualization and control without a touchscreen. This unit is part of the SIMATIC HMI Basic Panels generation and is intended for straightforward process monitoring and operator input tasks.

The OP 77A features a monochrome LCD display capable of showing multiple lines of text and simple graphics, with a membrane keypad for operator input including function keys and system keys. It supports the MPI and PROFIBUS DP communication interfaces for integration with SIMATIC S7 PLCs, and can also communicate via RS-422/RS-485 serial interfaces. The panel is configured using Siemens WinCC flexible software and supports alarm management, recipe handling, and trend display functions within its onboard memory capacity.

The SIMATIC OP 77A is widely used in manufacturing, packaging, and process automation environments where a cost-effective, robust operator interface is required at the machine level. Its compact form factor and panel-mount design make it suitable for integration into control cabinets and machine enclosures. Industries such as food and beverage, automotive assembly, and general factory automation commonly deploy this panel for local operator control and status monitoring.

Technical Specifications

Display Type	Monochrome LCD
Display Size	4 lines x 20 characters
Input/Operating Voltage	24 V DC
Power Consumption	Max. 4.5 W
Communication Interface	MPI, PROFIBUS DP, RS-422/RS-485
Operating Temperature	0 °C to +50 °C
Storage Temperature	-20 °C to +60 °C
Relative Humidity	10% to 90% (non-condensing)
IP/Protection Rating	IP65 (front panel)
Mounting	Panel mounting
Configuration Software	WinCC flexible 2005 or higher
Series/Product Family	SIMATIC HMI OP 77A
Certifications	CE, UL, cULus

Common Error Codes & System Events

Event ID: 10000: Communication error between the HMI panel and the connected PLC. The panel cannot establish or maintain a connection to the configured controller.
Check MPI or PROFIBUS DP cable connections and terminating resistors. Verify the PLC address settings match the HMI project configuration. Ensure the PLC is powered and in RUN mode.
Event ID: 10001: Connection to the PLC was interrupted during operation.
Inspect communication cables for damage or loose connections. Check bus termination and cable shielding. Restart both the HMI panel and the PLC if the connection does not recover automatically.
Event ID: 20000: Project download error. The configuration project could not be transferred to the panel successfully.
Verify the transfer cable and PC interface settings. Ensure WinCC flexible is configured for the correct communication port and panel type. Retry the download after restarting the panel in transfer mode.
Event ID: 40000: System memory low. The panel's available memory for runtime data is critically low.
Reduce the number of active alarms or recipe entries in the project. Optimize the project configuration in WinCC flexible to reduce memory usage and re-download the project.
Event ID: 50000: Configuration error detected. The loaded project contains settings incompatible with this panel variant.
Verify the project was compiled for the OP 77A panel type in WinCC flexible. Recompile and re-download the correct project to the panel.
Event ID: 60000: Internal device error or hardware fault detected on the panel.
Perform a power cycle on the panel. If the error persists, perform a factory reset. If the fault remains after reset, the panel may require repair or replacement.
Event ID: 70000: Alarm buffer overflow. The number of pending alarms has exceeded the buffer capacity.
Acknowledge and clear existing alarms on the panel. Review the alarm configuration in WinCC flexible to reduce the frequency or number of simultaneous alarms.

Frequently Asked Questions

Which PLCs are compatible with the Siemens OP 77A (6AV6355-1AA31-8DL7)?

The OP 77A is primarily designed for use with Siemens SIMATIC S7-200, S7-300, and S7-400 PLCs via MPI or PROFIBUS DP interfaces. It can also connect to S7-200 via RS-485 PPI protocol.

What software is required to configure and program the OP 77A?

The OP 77A is configured using Siemens WinCC flexible 2005 or a later compatible version. The project is then transferred to the panel via a PC adapter cable or MPI/PROFIBUS connection.

What is the supply voltage for the 6AV6355-1AA31-8DL7?

The panel operates on a 24 V DC supply voltage. Ensure the power supply is within the specified tolerance range to prevent operational faults.

Does the OP 77A support touchscreen input?

No, the OP 77A is a key-operated panel and does not feature a touchscreen. Operator input is performed via the integrated membrane keypad, which includes function keys and navigation keys.

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

The front panel of the OP 77A carries an IP65 protection rating, making it suitable for installation in environments where dust and water jets may be present.

Troubleshooting

Display remains blank after power on

Measure the 24 V DC supply voltage at the panel's power connector. Check that the supply is within the specified tolerance. Inspect the connector for secure contact.

Restore the 24 V DC supply to the correct level. If the supply is correct and the display remains blank, the internal power supply or LCD backlight may have failed, requiring panel repair or replacement.

Panel shows 'No connection to PLC' message during operation

Check the MPI or PROFIBUS DP cable between the panel and the PLC. Verify bus termination resistors are correctly placed at both ends of the bus. Confirm the PLC node address matches the address configured in the HMI project.

Replace or reseat the communication cable. Correct bus termination. Adjust the PLC address in the WinCC flexible project to match the physical PLC configuration and re-download the project.

Project download fails or panel does not enter transfer mode

Confirm the panel is set to transfer mode via the panel's start screen or loader menu. Check the PC adapter cable type and the COM port settings in WinCC flexible match the physical connection.

Restart the panel and manually select transfer mode from the loader. Verify the correct PC adapter driver is installed and the correct COM port is selected in WinCC flexible. Retry the project download.

Function keys do not respond or produce incorrect actions

Check the project configuration in WinCC flexible to verify that function key assignments are correctly defined. Test individual keys to determine if the issue is with a specific key or all keys.

Re-download the correct project to the panel. If a specific key is physically unresponsive, the membrane keypad may be worn or damaged and the panel may require servicing.

Alarms are not displayed or acknowledged on the panel

Verify that alarm tags are correctly linked to PLC data addresses in the WinCC flexible project. Check that the PLC communication is active and the alarm bits are being set correctly by the PLC program.

Correct the alarm tag configuration in WinCC flexible and re-download the project. Confirm the PLC program logic is correctly setting the alarm trigger bits and that communication between the panel and PLC is functioning.

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