Siemens 6AV6355-1AA47-7DL6 OP 77A

€ 3.495,00

SKU: 6AV6355-1AA47-7DL6 Category: HMI & Display Brand: Siemens

Description
Additional information

The Siemens 6AV6355-1AA47-7DL6 is an operator panel belonging to the SIMATIC HMI OP 77A series, manufactured by Siemens. It is a compact, key-operated panel designed for machine-level human-machine interface applications, providing operators with a straightforward means of monitoring and controlling automation processes. The OP 77A is part of the SIMATIC HMI Basic Panels generation and is intended for use with Siemens SIMATIC S7 controllers.

The OP 77A features a monochrome LCD display with a resolution of 160 x 64 pixels and a membrane keypad for operator input, eliminating the need for a touchscreen. It supports the MPI and PROFIBUS DP communication interfaces for direct connection to SIMATIC S7-200, S7-300, and S7-400 PLCs. The panel is configured using WinCC flexible Compact or Standard engineering software and supports basic alarm management, recipe handling, and trend display functions. It 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 typically deployed in machine building, packaging, food and beverage, and general manufacturing environments where a cost-effective, robust operator interface is required. Its compact form factor and keypad-based operation make it well suited for panel door mounting in control cabinets with limited space. The panel is commonly used in applications where simple process visualization, parameter entry, and alarm acknowledgment are the primary operator tasks.

Technical Specifications

Display Type	Monochrome LCD
Display Resolution	160 x 64 pixels
Input/Operating Voltage	24 V DC
Power Consumption	4 W (typical)
Communication Interface	MPI, PROFIBUS DP
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
Engineering Software	WinCC flexible Compact / Standard
Series/Product Family	SIMATIC HMI OP 77A
Certifications	CE, UL

Common Error Codes & System Events

Event ID: 1003: No connection to the PLC or controller. Communication between the OP 77A and the configured SIMATIC controller has been interrupted.
Check MPI or PROFIBUS DP cable connections and terminating resistors. Verify the configured station address and baud rate match the controller settings. Restart the panel if the connection is not re-established automatically.
Event ID: 1004: Connection to the PLC was interrupted during operation. The panel lost communication with the controller after an initial successful connection.
Inspect cabling for loose connectors or cable damage. Verify network topology and bus termination. Check PLC for faults or power interruptions.
Event ID: 10000: System memory low. The panel's available runtime memory is insufficient for the current project.
Reduce the number of active alarms or recipe entries. Simplify the project configuration and reload the project via WinCC flexible.
Event ID: 1703: Project transfer error. A project download from the engineering PC to the panel was not completed successfully.
Check the transfer cable or network connection between the PC and the panel. Ensure WinCC flexible version is compatible with the panel firmware. Retry the transfer.
Event ID: 2501: Alarm buffer overflow. The number of pending alarms has exceeded the panel's alarm buffer capacity.
Acknowledge and clear existing alarms. Review the alarm configuration in WinCC flexible to reduce the number of simultaneously active alarms.
Event ID: 1700: No project loaded on the panel. The panel has started but no valid runtime project is present in memory.
Transfer a valid project to the panel using WinCC flexible via MPI or PROFIBUS DP connection. Ensure the project is compiled without errors before transfer.
Event ID: 3000: Operating system error or firmware fault detected during panel startup.
Perform a factory reset by accessing the panel's loader menu. If the fault persists, update the panel firmware using the Siemens ProSave tool or contact Siemens technical support.

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 OP 77A?

The OP 77A is configured using Siemens WinCC flexible Compact or WinCC flexible Standard engineering software. The project is then transferred to the panel via MPI, PROFIBUS DP, or a serial PC/PPI cable.

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

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

Does the OP 77A support touchscreen input?

No, the OP 77A uses a membrane keypad for operator input and does not feature a touchscreen. All navigation and data entry is performed via the physical function and system keys.

What is the supply voltage required for the OP 77A?

The OP 77A requires a 24 V DC supply voltage. This is typically provided by a SITOP or equivalent regulated DC power supply unit.

Troubleshooting

Display remains blank after power on

Check that 24 V DC is present at the power supply terminals of the panel using a multimeter. Verify the power supply polarity is correct and the supply current capacity is sufficient.

Ensure the 24 V DC supply is stable and within tolerance. If the supply is correct and the display remains blank, the internal power supply board or backlight may be faulty and the unit should be sent for repair or replacement.

Panel shows 'No connection to PLC' message continuously

Verify the MPI or PROFIBUS DP cable is securely connected at both the panel and the PLC. Check that bus termination resistors are correctly placed at both ends of the network segment.

Correct any wiring faults and ensure the station address and baud rate configured in WinCC flexible match the PLC settings. Replace the communication cable if it is damaged. Restart both the panel and the PLC.

Project transfer from WinCC flexible fails or times out

Check the physical connection between the engineering PC and the panel, whether via MPI adapter, PROFIBUS DP, or serial cable. Confirm the panel is in transfer mode by accessing the loader menu.

Set the panel to transfer mode manually via the loader. Ensure the WinCC flexible version is compatible with the panel firmware version. Try a different communication cable or adapter if the issue persists.

Operator keys are unresponsive or register incorrect inputs

Inspect the membrane keypad surface for physical damage, contamination, or deformation. Test each key systematically in the panel's service or test mode if available.

Clean the keypad surface with a dry cloth. If keys are physically damaged or the membrane is worn, the keypad membrane assembly should be replaced. Contact a qualified repair technician for membrane replacement.

Panel repeatedly restarts or enters an error loop on startup

Attempt to access the loader menu during startup by pressing the appropriate key combination. Check whether a valid project is loaded and whether the firmware version is current.

Use Siemens ProSave to update the panel firmware to the latest compatible version. If no valid project is present, transfer a new project via WinCC flexible. If the restart loop continues after firmware update, the panel hardware may require professional repair.

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