Siemens 6AV6355-1AA47-7DK2 OP 77A

€ 955,52

SKU: 6AV6355-1AA47-7DK2 Category: HMI & Display Brand: Siemens

Description
Additional information

The Siemens 6AV6355-1AA47-7DK2 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. The OP 77A provides a text-based display interface for monitoring and controlling automation processes connected to Siemens SIMATIC controllers.

The OP 77A features a monochrome LCD display capable of showing multiple lines of text and numeric values, with a membrane keypad for operator input. It supports MPI and PROFIBUS DP communication interfaces, enabling direct connection to S7-200, S7-300, and S7-400 PLCs. The panel is configured using WinCC flexible software and supports recipe management, alarm logging, and trend display functions. It operates on a 24 V DC supply and is built to withstand industrial environments with a front panel protection rating of IP65.

The OP 77A is widely used in manufacturing, packaging, and process automation applications where a cost-effective, robust operator interface is required at the machine level. Its compatibility with the SIMATIC S7 controller family makes it suitable for integration into existing Siemens automation architectures. The panel is commonly found on conveyor systems, pumping stations, and general-purpose machine control panels where text-based status display and parameter entry are sufficient.

Technical Specifications

Display Type	Monochrome LCD
Display Lines	4 lines of text
Input/Operating Voltage	24 V DC
Power Consumption	Max. 6 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)
Configuration Software	WinCC flexible 2008
Mounting	Panel mounting
Certifications	CE, UL
Series/Product Family	SIMATIC HMI OP 77A

Common Error Codes & System Events

Event ID: 10000: Configuration error: No project loaded or project is incompatible with the panel firmware.
Download a compatible project using WinCC flexible. Verify firmware version matches the project settings.
Event ID: 10001: Communication error: Connection to the configured PLC cannot be established.
Check MPI or PROFIBUS DP cable connections and bus termination. Verify PLC address settings match the project configuration.
Event ID: 20000: System error: Internal device fault detected.
Perform a power cycle. If the fault persists, check the 24 V DC supply voltage and replace the unit if necessary.
Event ID: 40000: Alarm buffer overflow: The alarm buffer has reached its maximum capacity.
Acknowledge and clear pending alarms. Review alarm configuration to reduce alarm frequency or increase buffer size in the project.
Event ID: 50000: Recipe data error: Recipe record cannot be read or written.
Check recipe configuration in WinCC flexible. Verify PLC data block addresses assigned to recipe variables are correct and accessible.
Event ID: 60000: Tag update error: A configured process tag cannot be read 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 conflicts.
Event ID: 70000: Firmware update error: Firmware transfer to the panel was interrupted or failed.
Restart the firmware update procedure using ProSave or WinCC flexible. Ensure stable 24 V DC supply during the update process.

Frequently Asked Questions

Which PLCs are compatible with the OP 77A?

The OP 77A is compatible with Siemens SIMATIC S7-200, S7-300, and S7-400 PLCs via MPI or PROFIBUS DP interfaces. It can also communicate with S7-200 via PPI protocol.

What software is used to configure the OP 77A?

The OP 77A is configured using Siemens WinCC flexible 2008 software. Projects are transferred to the panel via MPI cable or USB using the ProSave utility.

What is the supply voltage for the OP 77A?

The OP 77A requires a 24 V DC power supply with a maximum power consumption of approximately 6 W.

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 spray may be present.

Can the OP 77A display graphical content?

The OP 77A is a text-based operator panel and does not support graphical display of process images. It is designed for alphanumeric text, numeric values, and alarm messages only.

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 correct polarity and verify the supply is within the specified voltage range.

Correct the supply voltage or wiring if out of specification. If the supply is correct and the display remains blank, the internal power supply or display unit may be faulty and the panel should be repaired or replaced.

No communication with PLC

Check the MPI or PROFIBUS DP cable for physical damage and verify correct bus termination at both ends of the network. Confirm the PLC address configured in the WinCC flexible project matches the actual PLC MPI/PROFIBUS address.

Replace damaged cables, correct bus termination resistors, and ensure address settings in the project match the PLC configuration. Reload the project to the panel after making corrections.

Panel displays 'No project' or fails to start the runtime

The panel may not have a valid project loaded, or the loaded project may be incompatible with the installed firmware version.

Use WinCC flexible or ProSave to download a compatible project to the panel. Verify that the firmware version on the panel matches the version required by the project, and update firmware if necessary.

Alarms are not displayed or acknowledged correctly

Check the alarm configuration in the WinCC flexible project, including the PLC bit addresses assigned to alarm triggers. Verify the PLC program is setting the correct alarm bits.

Correct the alarm tag addresses in the project to match the PLC program. Re-download the project and test alarm triggering from the PLC side.

Panel keypad buttons are unresponsive

Inspect the membrane keypad for physical damage or contamination. Attempt a power cycle to rule out a temporary software lockup.

Clean the keypad surface if contamination is present. If individual keys remain unresponsive after power cycling, the membrane keypad assembly is likely worn or damaged and should be replaced.

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