\documentclass[a4paper]{article}

\begin{document}

% insert table
%% use as \tabin{size_in_mm}{label}{caption}{table_data}
\newcounter{tabcounter}
\long\def\tabin #1#2#3#4{
\refstepcounter{tabcounter} \label{#2}
 \begin{center}\makebox[#1mm][c]{#4}\end{center} 
%\vspace{0mm}
\begin{center}
 \parbox{7cm}{{\bf TABLE \arabic{tabcounter}:}\quad {\it #3 } } \\
\end{center}
}



is set as must, then I used


\tabin{80}{first}{First set of experiments}{
    \begin{tabular} {|c| c| c| c| c| c|}
    \hline
    telegram number & 1 & 2 & 3 & 4 & 5 \\ \hline
    priority & 1 & 3 & 2 & 5 & 2 \\ \hline
    $S_m$ [B] & 8 & 8 & 8 & 8 & 8 \\ \hline
    $J_m$ [$\mu$s] & 25 & 25 & 25 & 25 & 25 \\ \hline   
    \end{tabular}
}


\end{document}
