\version "2.12.2"

\layout {
    \context { \Score
           \remove "Volta_engraver" 
    }
}

testMusik =  \relative c'' {
  \repeat volta 2 {
    c1 \break
  } \alternative {
    { c1 \break }
    { c1 \break }
  }
  c1
}  

\score {
  \new Staff  \with { 
    \consists "Volta_engraver" 
    instrumentName = "Instrument"
    shortInstrumentName = "Instr."
  }
  <<
    \testMusik
  >>
}