An electrically-powered automated or semi-automated laboratory instrument intended to be used for the qualitative and/or quantitative in vitro determination of one or multiple coagulation components involved in haemostasis in a clinical specimen [e.g., performs tests such as prothrombin time (PT), partial thromboplastin time (PTT)]. Analyser design may incorporate spectrophotometry, turbidimetry, nephelometry, electrometry, electromagnetic and/or mechanical means of clot formation or end point detection.