Resolving Siemens OP77B Error 10001: Printer Not Recognized

1. Problem Overview

The Siemens SIMATIC OP 77B is a compact 4-inch operator panel used extensively in machine-level HMI applications. When an operator attempts to trigger a printout (alarm log, message log, recipe, or screen hardcopy), the panel can return Error 10001: "No printer is installed or a default printer has not been set up". The error is generated by the OP 77B runtime even when a physically compatible USB printer is connected to the panel's USB Type-A host port.

This failure mode is distinct from a generic communication error. Error 10001 specifically indicates that the OP 77B firmware has not enumerated a usable printer driver at the point the print job was queued. On the OP 77B, this is a configuration and firmware compatibility problem, not a hardware wiring fault.

2. Affected Hardware, Firmware, and Project Software

The OP 77B is the low-end successor to the OP 73 / OP 77A in the SIMATIC HMI Micro/Smart line. Because it ships without a CE-WinCE shell and without an expandable driver layer, the panel strictly supports the printer models compiled into the firmware image. Field engineers frequently encounter Error 10001 after replacing a working installation with a newer printer model that is not on the supported list.

3. Root Cause Analysis

Error 10001 is raised when one of the following conditions is true at the moment the print job is dispatched:

1. No printer is connected to the OP 77B USB host port. The panel's USB stack performs enumeration at job dispatch time. If no USB printer-class device responds, the runtime raises 10001 before any data is sent.
2. A USB hub is in the path but not powered correctly. The OP 77B USB port supplies limited bus power. Unpowered or under-spec hubs cause enumeration to fail intermittently.
3. The connected printer is not in the OP 77B's internal printer driver table. The OP 77B only enumerates printers whose USB device IDs match the compiled-in list. The EPSON TM-T88V, TM-T88IV, and several Citizen / Star models are recognized when running the correct panel firmware; the TM-T88VI and later ESC/POS-native USB models may not be.
4. The project was not compiled with a printer driver selected. In WinCC flexible, the project must explicitly assign a printer driver under Device Settings > Printer. If "No printer" or a non-existent driver is selected, the runtime cannot translate the print job to ESC/POS or PCL.
5. The USB cable length exceeds the USB 1.1 specification. Cables longer than 5 m without a hub will cause the panel to drop the device at enumeration.

4. Diagnostic Procedure

Follow this sequence to isolate the cause of Error 10001 before changing hardware:

1. Verify physical connection. Disconnect and reconnect the USB cable at both ends. Confirm the cable is USB 1.1/2.0 rated and shorter than 3 m. Avoid USB extension cables and unpowered hubs.
2. Power-cycle the panel. The OP 77B enumerates USB devices at boot. A device connected after boot may not be recognized until the next boot cycle, particularly on early firmware revisions.
3. Inspect the panel's USB port output voltage. Under no-load the port should measure 5.0 V ± 5%. If the voltage droops below 4.5 V when the printer is plugged in, the panel's internal regulator is failing or the printer's inrush current is too high. The OP 77B cannot supply more than 100 mA per the USB 1.1 standard.
4. Read the system event buffer. On the OP 77B, navigate to Start > Settings > System > Event Logger (if available via the service menu). Look for USB enumeration events immediately preceding the 10001 error.
5. Confirm the project printer setting. Open the WinCC flexible project, select the OP 77B device, and inspect Properties > Printer. The "Printer" dropdown must list a supported driver such as Epson ESC/POS compatible or Generic / Text only.
6. Try a known-good printer. Substitute a printer from the validated list (see Section 7). If a known-good printer works, the issue is driver compatibility with the original printer model.

5. Configuration Steps (WinCC flexible)

The OP 77B project must be configured in WinCC flexible so that the runtime knows which built-in driver to invoke. The "default printer" referenced in the error text is therefore a project-side setting, not an OS-level default.

1. Open the WinCC flexible project that targets the OP 77B.
2. In the project tree, right-click the OP 77B device and choose Properties.
3. Select the Printer tab.
4. From the Printer dropdown, choose one of the supported drivers:

• Epson ESC/POS compatible (24 column)
• Epson ESC/POS compatible (40 column)
• Generic / Text only

5. Set the paper width to match the installed roll (typically 80 mm or 58 mm).
6. Click OK and recompile the project.
7. Transfer the compiled runtime to the OP 77B via MPI/PROFIBUS, Ethernet (where available), or USB-PPI.
8. After transfer, the panel will reboot. Verify the printer is connected before the panel finishes booting.

6. Configuration Steps (Direct on the Panel)

The OP 77B exposes a limited set of printer options from its on-board setup menu. These are useful when no engineering station is available:

1. Enter the panel's setup menu (tap the empty area during boot, or use the service menu combination).
2. Navigate to Printer Settings.
3. Select Printer Language. Available options depend on the compiled project but typically include:
   • ESC/POS
   • PCL
   • Text mode
4. Select the paper width and character set.
5. Save and reboot.

If the Printer Language field is greyed out or missing, the project itself does not contain a valid printer driver, and WinCC flexible must be used to correct the project.

7. Printer Compatibility Matrix

The following matrix is derived from the OP 77B firmware driver table and Siemens support note Entry ID 11376409. Engineers should validate against the latest Siemens support note before commissioning.

8. Wiring and Electrical Considerations

Even with a compatible printer, electrical problems at the USB layer will surface as Error 10001. Confirm the following before declaring the configuration correct:

9. Verification

After applying the configuration changes, perform the following verification steps:

1. Cycle power on the OP 77B with the printer already powered and connected.
2. Trigger a screen hardcopy: press and hold the print key (or the configured soft key) on the OP 77B.
3. Confirm the printer produces a single line of text and feeds paper.
4. Trigger an alarm or message printout and verify the time-stamped line matches the event log.
5. Re-enter the panel's setup menu and confirm Printer Settings > Printer Language shows the selected driver.
6. Inspect the event logger for any further 10001 events. A clean run for 24 hours with normal alarm traffic confirms the fix.

10. Workarounds and Alternatives

When the printer of choice is not on the supported list and replacement is not feasible, consider the following alternatives:

• Use the OP 77B's serial port to a serial printer. The OP 77B has a built-in RS-232 (RS-422 optional) port on the lower terminal block. With the appropriate WinCC flexible project setting, ESC/POS-capable serial printers such as the Epson TM-U220 can be driven directly. This path bypasses the USB enumeration problem entirely.
• Migrate to a newer panel. The SIMATIC KTP400 Comfort, KTP700 Comfort, or TP700 Comfort supports a broader printer list including the TM-T88VI and Star TSP100-series. Error 10001 is replaced by a richer driver management interface in the Comfort runtime.
• Use a print server. A small embedded print server (e.g., a Raspberry Pi running CUPS) can capture print jobs from a higher-level SCADA via Ethernet and forward them to a USB or network printer. This is appropriate when the OP 77B is being retained for cost reasons but a non-supported printer is required at the plant.
• Replace the OP 77B with a Smart 700 IE / Smart 1000 IE. These panels retain the OP 77B form factor but include modern driver support and Ethernet, eliminating Error 10001 for most modern ESC/POS printers.

11. Troubleshooting Matrix

12. Related Siemens Documentation

For deeper background, consult the official Siemens support note that catalogs supported printers for the OP 77B and adjacent panels:

• Siemens Support Entry 11376409 — Supported printers for SIMATIC OP 77B

Engineers should always verify the latest revision of this entry before selecting a printer for a new installation, as the supported list can be extended by firmware updates.

13. Frequently Asked Questions