Siemens 6AV6355-1AA47-7EM0 OP 77A

€ 1.995,00

SKU: 6AV6355-1AA47-7EM0 Category: HMI & Display Brand: Siemens

Description
Additional information

The Siemens 6AV6355-1AA47-7EM0 is an Operator Panel (OP 77A) belonging to the SIMATIC HMI Basic Panels product family. This compact operator panel is designed for straightforward machine-level visualization and control tasks, providing a reliable human-machine interface solution for industrial environments. It is manufactured by Siemens as part of the SIMATIC HMI portfolio, targeting entry-level to mid-range panel applications.

The OP 77A features a monochrome STN LCD display with a resolution of 128 x 64 pixels, capable of displaying text and simple graphics. It supports communication via MPI and PROFIBUS DP interfaces, enabling direct integration with SIMATIC S7-200, S7-300, and S7-400 PLCs. The panel includes function keys and a numeric keypad for operator input, and is configured using WinCC flexible software. It operates on a 24 V DC supply and is rated to IP65 on the front face for protection against dust and water ingress.

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 compact form factor and front-face IP65 protection make it suitable for panel-mount installations in industrial control cabinets and machine enclosures. Industries such as automotive, food and beverage, and general machinery manufacturing commonly deploy this panel for local operator control and status monitoring.

Technical Specifications

Display Type	Monochrome STN LCD
Display Resolution	128 x 64 pixels
Display Colors	Monochrome (blue/white)
Input Voltage	24 V DC
Power Consumption	4.5 W (typical)
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 mount
Configuration Software	WinCC flexible 2008
Series/Product Family	SIMATIC HMI OP 77A

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 controller.
Check MPI or PROFIBUS DP cable connections and termination 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 physical cable integrity and connector seating. Check for electromagnetic interference sources near the communication cable. Restart the HMI panel and verify PLC communication parameters.
Event ID: 20000: Project download error. The configuration project could not be transferred to the panel successfully.
Verify the USB or serial transfer cable is correctly connected. Ensure WinCC flexible project is compiled without errors before transfer. Check available memory on the panel.
Event ID: 40000: System memory low. The panel is running low on available runtime memory.
Reduce the number of active alarms or logged data entries. Simplify the project if possible. Consider clearing the alarm buffer via the panel's system menu.
Event ID: 50000: Internal device error or hardware fault detected during self-test at startup.
Perform a power cycle. If the error persists, back up the project and perform a factory reset via the panel's loader menu. Contact Siemens support if the fault recurs after reset.
Event ID: 60000: Configuration error detected. The loaded project is incompatible with the panel firmware version.
Update the panel firmware to the version compatible with the WinCC flexible project. Re-download the project after ensuring version compatibility between WinCC flexible and the panel OS.
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 unnecessary alarm triggers. Increase the alarm buffer size if supported by the project settings.

Frequently Asked Questions

Which PLCs are compatible with the Siemens OP 77A (6AV6355-1AA47-7EM0)?

The OP 77A is compatible with SIMATIC S7-200, S7-300, and S7-400 PLCs via MPI or PROFIBUS DP communication 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 a PC adapter cable connected to the MPI interface or via USB transfer cable depending on the panel variant.

What is the supply voltage for the 6AV6355-1AA47-7EM0?

The panel operates on a 24 V DC supply voltage. The power consumption is approximately 4.5 W under typical operating conditions.

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

The front face of the OP 77A is rated to IP65, providing protection against dust ingress and low-pressure water jets. The rear of the panel is rated IP20.

Can the OP 77A display graphics and images?

The OP 77A supports simple graphics and bitmap images on its 128 x 64 pixel monochrome LCD display. Complex color graphics are not supported due to the monochrome display technology.

Troubleshooting

Display remains blank after power on

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

Restore the correct 24 V DC supply if voltage is absent or out of range. If supply is correct and display remains blank, the internal power supply or LCD backlight may have failed and the panel should be sent for repair or replacement.

Panel shows 'No connection to PLC' or communication error on screen

Inspect the MPI or PROFIBUS DP cable for physical damage, loose connectors, or missing bus termination resistors at both ends of the network. Verify the PLC station address configured in the HMI project matches the actual PLC address.

Replace or reseat the communication cable. Install correct bus termination resistors at the network endpoints. Correct the PLC address in the WinCC flexible project and re-download the configuration to the panel.

Panel is stuck in loader screen and does not start the runtime project

This typically indicates a corrupted or missing runtime project on the panel, or a firmware version mismatch between the panel OS and the project.

Connect the panel to a PC running WinCC flexible and re-transfer the project. If the loader is inaccessible, perform a factory reset by holding the appropriate key combination during power-on as described in the OP 77A operating instructions, then re-download the project.

Function keys do not respond to operator input

Check whether the panel is in transfer mode or loader mode, which disables runtime key functions. Also inspect the keypad membrane for physical damage or contamination around the key area.

Exit transfer or loader mode by selecting the runtime option from the loader menu. If keys are physically damaged or unresponsive due to contamination, the keypad membrane assembly requires replacement.

Alarm messages are not displaying correctly or alarm buffer is full

Access the alarm view on the panel and check the number of pending unacknowledged alarms. Review the WinCC flexible project alarm configuration for misconfigured triggers or excessively sensitive alarm conditions.

Acknowledge and clear all pending alarms. In WinCC flexible, review and correct alarm trigger conditions and set appropriate alarm priorities. Increase the alarm buffer size in the project settings if repeated overflow occurs.

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