Siemens 6AV6355-1AA47-7CA3 OP 77A

€ 3.495,00

SKU: 6AV6355-1AA47-7CA3 Category: HMI & Display Brand: Siemens

Description
Additional information

The Siemens 6AV6355-1AA47-7CA3 is the OP 77A operator panel, part of the SIMATIC HMI Basic Panels product family. This compact operator panel is designed for straightforward machine-level human-machine interface tasks and belongs to Siemens' established line of text-based HMI devices. It provides a clear alphanumeric display for status monitoring and operator input in industrial control environments.

The OP 77A features a 4-line STN LCD text display capable of showing alphanumeric characters, with a membrane keypad for operator input including function keys and system keys. It supports MPI and PROFIBUS DP communication interfaces for direct integration with SIMATIC S7 PLCs. The unit operates on 24 V DC supply voltage and is built to withstand industrial environments, with a front panel protection rating of IP65. Configuration is performed using WinCC flexible software.

The OP 77A is widely used in machine building, manufacturing automation, and process control applications where a cost-effective, reliable text-based operator interface is required. It is suitable for tasks such as displaying process values, entering setpoints, acknowledging alarms, and navigating simple menu structures. Typical industries include automotive manufacturing, food and beverage processing, packaging machinery, and general factory automation.

Technical Specifications

Display Type	STN LCD, alphanumeric text display
Display Lines	4 lines
Characters per Line	20 characters
Input/Operating Voltage	24 V DC
Permissible Voltage Range	19.2 V DC to 28.8 V DC
Power Consumption	Max. 4.5 W
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
Certifications	CE, UL, cULus
Configuration Software	WinCC flexible 2005 or higher

Common System Event Codes

System Event 10000: Communication error between the HMI panel and the connected PLC. The connection to the configured controller has been interrupted.
Check MPI or PROFIBUS DP cable connections and termination resistors. Verify the PLC is powered and in RUN mode. Check the configured station address and baud rate in WinCC flexible.
System Event 10001: Connection to PLC established after a previous communication failure.
Informational event. No corrective action required. Monitor for recurring communication interruptions that may indicate an unstable network.
System Event 10002: Tag read error. The HMI panel cannot read the value of a configured tag from the PLC.
Verify the tag address configured in WinCC flexible matches the actual PLC data block or memory address. Check that the PLC program is running and the relevant data area is accessible.
System Event 10003: Tag write error. The HMI panel cannot write a value to the configured PLC tag.
Check that the target PLC memory area is not write-protected. Verify the tag address and data type configuration in WinCC flexible. Ensure the PLC is in RUN mode.
System Event 40000: Project download error. Transfer of the HMI project to the panel was not completed successfully.
Check the transfer cable connection. Ensure the panel is in Transfer mode. Verify the WinCC flexible project is free of configuration errors before retrying the download.
System Event 70010: Insufficient memory on the HMI device. The project or runtime data exceeds the available panel memory.
Reduce the project size by removing unused screens, tags, or alarm messages. Recompile and re-download the project using WinCC flexible.
System Event 20000: Alarm buffer overflow. The number of pending alarms exceeds the alarm buffer capacity of the panel.
Acknowledge and clear existing alarms. Review the alarm configuration in WinCC flexible to reduce the number of simultaneously active alarms or increase acknowledgment frequency.

Frequently Asked Questions

Which PLCs are compatible with the OP 77A?

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 communicate with S7-200 via PPI protocol.

What software is required to configure the OP 77A?

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

What is the supply voltage for the 6AV6355-1AA47-7CA3?

The OP 77A requires a 24 V DC supply voltage, with a permissible operating range of 19.2 V DC to 28.8 V DC.

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 control cabinet doors where it may be exposed to dust and water spray.

Can the OP 77A display graphics or only text?

The OP 77A is a text-based operator panel and displays alphanumeric characters only. It does not support graphical screens or bitmap images.

Troubleshooting

Display remains blank after power on

Check the 24 V DC supply voltage at the power connector using a multimeter. Verify the voltage is within the 19.2 V to 28.8 V range. Inspect the supply cable and connector for damage.

Restore the correct 24 V DC supply voltage. If voltage is correct and the display remains blank, the internal power supply or display unit may be faulty and the panel should be sent for repair or replacement.

HMI shows communication error or no connection to PLC

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

Replace or reseat the communication cable. Correct the station address and baud rate in the WinCC flexible project and re-download. Ensure only the two physical end nodes on the bus have termination resistors enabled.

Project transfer to panel fails or times out

Confirm the panel is set to Transfer mode by navigating to the transfer settings on the panel. Check the PC adapter cable (PC/MPI or PC/PPI) is correctly installed and the COM port or USB driver is functioning on the engineering PC.

Restart the panel in Transfer mode and retry the download from WinCC flexible. If using a PC/MPI adapter, verify the adapter baud rate matches the project settings. Try a different USB port or reinstall the adapter driver if the issue persists.

Function keys do not respond or produce incorrect actions

Check the WinCC flexible project configuration to verify the correct function key assignments are programmed. Inspect the membrane keypad for physical damage or contamination under the keys.

Re-download the correct project to the panel to restore proper key assignments. If keys are physically damaged or unresponsive due to membrane wear, the keypad membrane assembly requires replacement.

Alarm messages are not displayed or acknowledged correctly

Review the alarm configuration in WinCC flexible to confirm alarm tags are correctly mapped to PLC addresses. Check that the PLC program is setting and resetting the alarm bits as expected.

Correct any misconfigured alarm tag addresses in WinCC flexible and re-download the project. Verify PLC logic for alarm bit control. Clear the alarm buffer on the panel if it has reached capacity.

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