We will need:
- GhostScript (link)
- Plot (placed in %PDMSEXE%\Plot\ + also need %PDMSEXE%\libifcoremd.dll and%PDMSEXE%\libmmd.dll)
- and .bat file
Installing GhostScript (or take from somewhere : gsdll32.dll and gswin32c.exe)
(Probably for 64-bit version names will be different)
Then create any work directory ( example: D:\Temp\), and inside it, such hierarchy : 
In folder 00_gs place binary files of GhostScript’а
In folder 01_plot place: plot.exe, zlib.dll , libifcoremd.dll, libmdd.dll
In that folder root, create .bat file with name create_pdf.bat :
@echo off setlocal EnableDelayedExpansion EnableExtensions set currentfolder=%~dp0 set gsexe="%currentfolder%00_gs\gswin32c.exe" set plotexe="%currentfolder%01_plot\plot.exe" set inputfolder=%currentfolder%input\ set outputfolder=%currentfolder%output\ set tempfolder=%currentfolder%temp\ rem -- Delete all files from temp and output del /F /Q %tempfolder%\* del /F /Q %outputfolder%\* rem -- Converting PLT files into PS for /f %%f in ('dir /b %inputfolder%\*') do %plotexe% ps "%inputfolder%%%f" "%tempfolder%%%f.ps" rem -- Converting each PS into PDF (bacause of issue in the PS) for /f %%f in ('dir /b %tempfolder%\*.ps') do %gsexe% -dSAFER -dBATCH -dNOPAUSE -sPAGESIZE=a1 -sDEVICE=pdfwrite -sOutputFile=%tempfolder%%%f.pdf -dAutoRotatePages=/PageByPage -dPDFFitPage -c "<</Orientation 3>> setpagedevice 0 rotate " -f %tempfolder%%%f rem -- Gathering PDFs into filelist for GS set "strGsInput=" for /f %%f in ('dir /b %tempfolder%\*.pdf') do set strGsInput=!strGsInput! "%tempfolder%%%f" rem -- Merging into the output PDF %gsexe% -dSAFER -dBATCH -dNOPAUSE -sPAGESIZE=a1 -sDEVICE=pdfwrite -sOutputFile=%outputfolder%output.pdf -f %strGsInput% rem -- Delete all files from temp and output del /F /Q %tempfolder%\* endlocal
Now we have everything to create PDF files..
Place inside folder input our .plt files and run script create_pdf.bat.
As a result inside folder output we will get multipage output.pdf
Thanks to vladimir.degtyar
