Siemens MP277 VBScript CSV Logging with Time-Stamped Filenames

Overview

Siemens MP277 operator panels running Windows CE 5.0 and engineered with WinCC Flexible 2008 (SP2 through SP5) provide a VBScript runtime that allows the HMI application to write tag values directly to comma-separated value (CSV) files. The most common field request is to give each saved file a time-stamped name so that successive runs of the same script produce an independent log file rather than overwriting a single hard-coded path. The challenge is that the panel's local VBScript Now function returns a value containing the : separator (e.g., 10:22:55), which is illegal in Windows file systems.

This reference covers the full path from the original problem statement (a panel script writing three tags A, B, C to \flash\AA.csv) through the corrected implementation, including the official Siemens support references for the FileCtl.File object, time/date masking, network path redirection, and a clean migration path into TIA Portal WinCC scripting for the SIMATIC Comfort Panel successors.

Prerequisites

• SIMATIC MP277 (8" or 10") operator panel, or equivalent 270/277 series panel, firmware V12.02.00 or later (Windows CE 5.0 image).
• WinCC Flexible 2008 SP5 (the final service pack that supports the MP277) or WinCC Flexible 2008 SP3/SP4 with the corresponding HSPs installed.
• A configured HMI project with at least three tags (A, B, C in the example) declared in the tag table of type Int, Real, or String.
• VBScript editor access within the project: Project > Scripts > VB Scripts.
• For network export, an Ethernet connection from the MP277 to a Windows PC sharing a folder, with read/write permission for the user account under which the panel is logging on. The MP277 does not support username/password authentication against the share without an additional configuration entry (see the Siemens FAQ 26106418 referenced for legacy panel scripting).
• For TIA Portal migration: TIA Portal V15.1 or later with WinCC Comfort/Advanced, and the migration tool Project > Migrate project if the existing WinCC Flexible project is being converted.

The Original Script and Why It Overwrites

The starting script posted in the source is functional but stores every sample in a single fixed path. The body of the script runs in the WinCC Flexible Runtime's VBScript host; the panel's SmartTags collection is the gateway to tag values, and the FileCtl.File ActiveX is the gateway to the local file system on the CE 5.0 image.

' Original script - fixed filename, no timestamp
Dim L1, L2, L3
L1 = HmiRuntime.SmartTags("A")
L2 = HmiRuntime.SmartTags("B")
L3 = HmiRuntime.SmartTags("C")

Dim fso, path
path = "\flash\AA.csv"
Set fso = CreateObject("FileCtl.File")
fso.Open path, 2         ' 2 = modeWrite (append is modeAppend = 8)
fso.WriteFields L1
fso.WriteFields L2
fso.WriteFields L3
fso.Close
Set fso = Nothing

On every execution the file at \flash\AA.csv is opened in write mode. FileCtl.Open on the MP277 resets the file pointer to the beginning of the file and replaces any existing content; only modeAppend = 8 preserves prior records. This is the first correction to apply whenever the goal is archival logging rather than a single live snapshot.

Naming Files with Time Components

VBScript exposes a number of date/time functions through its runtime. On Windows CE 5.0 the panel returns the current local time in the regional format configured under Control Panel > Regional Settings. The three most reliable techniques for the MP277 are documented below.

Method 1 - Direct concatenation of the Now string

path = "\flash\" & Now & ".csv"

This returns a string such as \flash\2/14/2025 10:22:55 AM.csv. It works inside the CE 5.0 file system because the \flash\ mount does not enforce the Windows reserved-character rules that apply to FAT, NTFS, or SMB shares. The drawback is that the resulting file name contains slashes and spaces, which complicates later parsing on a PC.

Method 2 - Mask the trailing eight characters

path = "\flash\" & Right(Now, 8) & ".csv"

Because Now is formatted as MM/DD/YYYY HH:MM:SS (24 characters) on the default US locale, Right(Now, 8) extracts the trailing HH:MM:SS portion. This produces a usable file name on the panel, but the colon is still present, which is the root cause of the source question: Windows XP/Vista/7/10 file systems reject the colon when the file is later copied to a PC share.

Method 3 - Build the time from individual parts (recommended)

path = "\flash\" & Hour(Now) & "_" & Minute(Now) & "_" & Second(Now) & ".csv"

The output for an execution at 10:22:55 is \flash\10_22_55.csv. This satisfies both the panel's file system and any subsequent Windows file system that the file may be copied to. The underscore separator is preferred over the dot because Windows relies on the final dot to detect the file extension.

Method 4 - Combine date and time for unique daily names

Dim ts
ts = Year(Now) & "-" & _
     Right("0" & Month(Now), 2) & "-" & _
     Right("0" & Day(Now), 2) & "_" & _
     Right("0" & Hour(Now), 2) & "-" & _
     Right("0" & Minute(Now), 2) & "-" & _
     Right("0" & Second(Now), 2)
path = "\flash\" & ts & ".csv"

This generates an ISO-style sortable name such as 2025-02-14_10-22-55.csv. Leading zeros are forced by the Right("0" & x, 2) pattern because Month(Now) returns a non-padded integer on CE 5.0. ISO 8601 ordering means directory listings sort chronologically on the Windows side without renaming.

Method 5 - FormatDateTime with named constants

path = "\flash\" & FormatDateTime(Now, vbShortTime) & ".csv"

On a CE 5.0 panel the result is 10:22; combined with a second pass on the seconds field you can rebuild an un-punctuated name. Note that FormatDateTime is locale-sensitive and may produce unexpected punctuation on a panel configured for a non-US regional setting - this is why Method 3 is the safest production choice.

Fixing the Windows File-System Restriction

The Windows file systems (FAT16/FAT32 on storage cards, NTFS on the destination PC, SMB on the network share) reserve the following characters and reject them inside a file name: < > : " / \ | ? *. ASCII codepoints 0-31 are also prohibited. The colon in particular is reserved by the DOS file system dating from the original IBM PC, and is reinforced by the Win32 layer on every supported Windows version.

The corrected full script that produces Windows-safe files is shown below. The path uses \flash\ (the internal persistent storage of the MP277). For archival volumes use \Storage Card\ when an SD card is fitted, but be aware that the CE 5.0 image only mounts the first FAT16 partition and limits the path length to 256 characters including the file name.

' Time-stamped CSV write - Windows-safe filename, append mode
Dim L1, L2, L3
L1 = HmiRuntime.SmartTags("A")
L2 = HmiRuntime.SmartTags("B")
L3 = HmiRuntime.SmartTags("C")

Dim fso, path
Dim h, m, s
h = Right("0" & Hour(Now), 2)
m = Right("0" & Minute(Now), 2)
s = Right("0" & Second(Now), 2)

path = "\flash\" & h & "_" & m & "_" & s & ".csv"

Set fso = CreateObject("FileCtl.File")
fso.LineSeparator = ";"   ' CSV field separator (WinCC default on MP277)

' 8 = modeAppend (preserve prior records), 2 = modeWrite (overwrite)
' For continuous logging use 8; for snapshot-per-file use 2
fso.Open path, 8
fso.WriteFields L1
fso.WriteFields L2
fso.WriteFields L3
fso.Close
Set fso = Nothing

Sending the CSV to a PC over Ethernet

The panel's CE 5.0 image can reach SMB shares on a PC, but the implementation does not support a credentialed logon dialog. The standard Siemens-documented procedure is to keep the file on the panel under \flash\ and use the panel's own services to copy it out at the end of a shift.

Option A - Sm@rtService / Sm@rtServer file transfer

Enable Sm@rtService in the panel properties and connect from a PC using Internet Explorer or the Sm@rtClient. The operator can browse the \flash\ tree and download the CSVs. The service uses HTTP on port 80 (or 1024+ as configured) and does not require a username; restrict access by IP allow-list in Control Panel > Network > Sm@rtService.

Option B - Network share with anonymous mapping

Configure the PC share to allow Everyone: Full Control with NTFS permissions mirroring that, then use the FileCtl copy function on the panel. Siemens' WinCC Flexible FAQ 26106418 documents the exact object invocation. The path syntax for a UNC target from the panel is:

path = "\\SERVER\share\" & h & "_" & m & "_" & s & ".csv"

Note the doubled backslashes; the first pair escapes the literal backslash, the second pair is the UNC path separator. If the share requires a credential, you must use the Configure_NetShare dialog on the panel (English CE 5.0 image only) or set the registry key HKEY_LOCAL_MACHINE\Services\SMB\Parameters\UseDefaultUser on the panel to inject a fixed account.

Option C - FTP push

Run a small FTP server on the PC (e.g., FileZilla Server) and have the panel push the CSV via the FTP OCX. The colon is rejected by NTFS, so the panel-side name masking is still required before the push.

Option D - Scheduled copy using the panel scheduler

Siemens' FAQ 13336639 covers a script-based scheduler that copies files from \flash\ to an SD card or to a network target every N minutes. Combine it with a 10-minute Schedule in WinCC Flexible that triggers the script and you reproduce the "save every 10 min, named by time" workflow asked in the source.

FileCtl.File Method Reference

The FileCtl.File object exposed by WinCC Flexible on the MP277 is a thin wrapper around the CE 5.0 file APIs. The following table documents the members that the source script and its variants depend on.

The full property/method set is enumerated in the WinCC Flexible 2008 SP5 online help under Programming > Reference > VBScript Reference > Objects > FileCtl.

Scheduled Logging Every 10 Minutes

To reproduce the "save every 10 minutes, name the file by time" requirement:

1. Open the WinCC Flexible project and select Schedules.
2. Add a new schedule named LogEvery10Min with trigger Periodic at 00:10:00.
3. Bind the schedule's On Trigger event to the script that contains the corrected body above.
4. For the example tags A, B, C, ensure they are Continuous acquisition tags with a 1 s update so that every 10-minute sample is meaningful.
5. To avoid duplicate file names when the trigger fires at the same wall-clock minute twice, append the schedule's ID using Format and Day(Now) so the file name includes the day: \flash\<YYYYMMDD>_<HHMMSS>.csv.
6. Stop the schedule with the HMI tag StopLogging if you need a clean run-up/shut-down at shift change.

Reading the Logged CSV Back from the Panel

Once a CSV is on the panel, the same FileCtl.File object reads it back into tag values for display. A typical reading script mirrors the writer:

Dim fso, path
path = "\flash\last.csv"
Set fso = CreateObject("FileCtl.File")
fso.LineSeparator = ";"
If fso.FileName = "" Then
    fso.Open path, 1            ' modeRead
End If
If Not fso.EOF Then
    Dim rec
    rec = fso.InputString
    SmartTags("LastA") = Split(rec, ";")(0)
    SmartTags("LastB") = Split(rec, ";")(1)
    SmartTags("LastC") = Split(rec, ";")(2)
End If
fso.Close
Set fso = Nothing

Migrating the Script to TIA Portal WinCC

Newer SIMATIC Comfort Panels (TP700/900/1200/1500, KP1500) run the same VBScript dialect under TIA Portal WinCC. The Siemens support entry 106501825 titled "How do you store data with a script in a file with WinCC (TIA Portal) PC Runtime?" documents the modern API and the relevant runtime settings. The key adaptations are:

• The ActiveX object is still FileCtl.File; the syntax shown above is portable. The path root for the internal storage is \flash\ on a Comfort Panel and C:\ProgramData\Siemens\Automation\WinCCRT\ on a PC Runtime.
• Tag access is the same: SmartTags("A") still resolves, but the newer runtime also supports HmiRuntime.SmartTags("A") interchangeably.
• The line separator defaults to ; in most regional builds. To produce strict RFC 4180 CSV output, set fso.LineSeparator = "," and add a manual fso.Write for the line terminator.
• For TIA Portal V18 and later the panel's Recipes & Logging object can be used as a higher-level alternative to FileCtl; it adds structured columns, auto-indexing, and integrated viewer controls.

Troubleshooting Matrix

Verification Procedure

After deploying the script, run the following checks before going to production:

1. Trigger the schedule manually via the panel's Service > Trigger Schedule and confirm a new file appears in \flash\ within one polling cycle of the runtime.
2. Open the resulting file with Notepad and confirm the time stamp in the file name matches the panel's Control Panel > Date/Time at the moment of trigger.
3. Copy the file to a Windows share using Sm@rtService. The transfer must succeed without renaming, proving the colon is no longer in the name.
4. Open the file in Excel using the comma separator; the values of A, B, C must appear in three distinct columns.
5. Re-trigger the schedule ten minutes later; a second file with a different time stamp must appear, and the first file must be unchanged (proving append semantics for other loggers in the same project).
6. Force a power-cycle of the panel. After reboot the files must still be present in \flash\ and the schedule must resume within the configured runtime recovery window (default 30 s).

FAQ