Siemens 6AV6355-1AA47-7EA2 OP 77A

€ 1.995,00

SKU: 6AV6355-1AA47-7EA2 Category: HMI & Display Brand: Siemens

Description
Additional information

The Siemens 6AV6355-1AA47-7EA2 is an operator panel belonging to the OP 77A series, part of the SIMATIC HMI family of human-machine interface devices. This compact panel is designed for machine-level operator control and monitoring tasks, providing a straightforward interface for process visualization in industrial environments. It is a key-operated panel featuring a monochrome display and a membrane keypad, suited for applications requiring reliable and robust local operation.

The OP 77A panel features a monochrome STN LCD display with a resolution of 160 x 80 pixels and a backlit screen for clear readability in varying ambient light conditions. It communicates via MPI and PROFIBUS DP interfaces, enabling direct integration with Siemens SIMATIC 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 within its onboard memory capacity.

The OP 77A is widely used in manufacturing, packaging, and process automation applications where a compact, cost-effective HMI solution is required at the machine level. Its robust membrane keypad and industrial-grade housing make it suitable for installation in control cabinets and machine panels exposed to dust and moisture. The panel is particularly common in applications involving conveyor systems, pumping stations, and general-purpose machine control.

Technical Specifications

Display Type	Monochrome STN LCD
Display Resolution	160 x 80 pixels
Display Size	4 inch (diagonal)
Input/Operating Voltage	24 V DC
Power Consumption	4 W (typical)
Communication Interface	MPI, PROFIBUS DP
Configuration Software	WinCC flexible 2005 or higher
Operating Temperature	0 °C to +50 °C
Storage Temperature	-20 °C to +60 °C
Relative Humidity	10% to 90% (non-condensing)
IP Rating (Front)	IP65
IP Rating (Rear)	IP20
Mounting	Panel mounting
Certifications	CE, UL, cULus
Series/Product Family	SIMATIC HMI OP 77A

Common Error Codes and System Events

Event ID: 10000: Configuration error: The project loaded on the panel is incompatible or corrupted.
Reload the project using WinCC flexible. Verify the project was compiled without errors before transfer.
Event ID: 20000: Communication error: No connection to the configured PLC or controller.
Check MPI or PROFIBUS DP cable connections and termination resistors. Verify PLC address settings match the HMI project configuration.
Event ID: 40000: Tag read error: A configured tag cannot be read from the PLC.
Verify the tag address exists in the PLC program and that the data type matches the HMI configuration. Check PLC is in RUN mode.
Event ID: 50000: Tag write error: A value cannot be written to the configured PLC tag.
Check that the PLC tag is not write-protected and that the HMI has write access. Verify the address and data type configuration in WinCC flexible.
Event ID: 70000: Alarm buffer overflow: The alarm buffer has reached its maximum capacity.
Acknowledge and clear pending alarms. Review alarm configuration to reduce unnecessary alarm triggers and increase buffer size if possible in the project settings.
Event ID: 110000: System memory low: Available system memory on the panel is critically low.
Reduce the number of active alarms or recipes stored on the device. Reload a simplified project or perform a factory reset and re-transfer the project.
Event ID: 130000: Backlight failure: The display backlight has failed or is operating outside normal parameters.
Check the operating hours of the backlight. If the panel has exceeded its backlight service life, arrange for panel repair or replacement of the backlight unit.

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 interfaces. It can also communicate with S7-200 via the PPI protocol depending on configuration.

What software is used to configure the Siemens 6AV6355-1AA47-7EA2?

The panel is configured using Siemens WinCC flexible 2005 or a later version. Projects are compiled and transferred to the panel via a PC adapter or MPI/PROFIBUS connection.

What is the supply voltage for the OP 77A?

The OP 77A operates on a 24 V DC supply voltage. Ensure the power supply is within the specified tolerance range to avoid damage or malfunction.

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 resistant to dust ingress and low-pressure water jets. The rear of the unit is rated IP20.

Can the OP 77A display graphical content or only text?

The OP 77A supports basic graphical elements including bar graphs, trend curves, and bitmap images in addition to text, within the constraints of its 160 x 80 pixel monochrome display.

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 that the voltage is within the specified tolerance. Inspect the backlight by observing the display at an angle in a darkened environment to determine if the LCD is active but the backlight has failed.

If supply voltage is incorrect, correct the power source. If the backlight has failed, the panel will require repair or replacement of the backlight assembly. If voltage is correct and the display is completely inactive, inspect internal fuses and consider panel replacement.

Panel displays 'No connection to PLC' or communication error on startup

Verify the MPI or PROFIBUS DP cable is securely connected at both the panel and PLC ends. Check bus termination resistors are correctly placed at both ends of the network. Confirm the PLC address and baud rate settings in the HMI project match the physical PLC configuration.

Correct any wiring faults or replace damaged cables. Adjust the PLC address and baud rate in the WinCC flexible project and re-transfer to the panel. Ensure termination resistors are enabled only at the physical ends of the bus.

Panel repeatedly reboots or freezes during operation

Check the 24 V DC supply for voltage dips or instability using a multimeter or oscilloscope. Inspect the project for memory overload conditions or excessively large alarm buffers. Verify the panel firmware version is compatible with the loaded WinCC flexible project version.

Stabilize the power supply by using a dedicated 24 V DC rail with adequate current capacity. Simplify the project if memory usage is excessive. Update the panel firmware to the latest compatible version using the Siemens ProSave tool.

Membrane keypad buttons are unresponsive or intermittently responsive

Inspect the membrane keypad surface for physical damage, contamination, or deformation. Test each key systematically in the panel's operating mode to identify whether the fault is isolated to specific keys or affects all keys.

Clean the keypad surface with a dry cloth. If individual keys are damaged or the membrane is worn, the keypad membrane assembly will need to be replaced. Contact a qualified repair service for membrane replacement on the OP 77A.

Project transfer from PC to panel fails

Verify the PC adapter or communication cable is correctly connected and the correct COM port or USB adapter is selected in WinCC flexible. Check that the panel is in transfer mode, which can be activated via the panel's start center or by holding the appropriate key combination during boot.

Switch the panel to transfer mode manually via the start center menu. Ensure the correct baud rate and interface settings are configured in WinCC flexible transfer settings. Replace the PC adapter cable if communication cannot be established after verifying all settings.

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