A robotic arm of an automated pipetting system comprising: a pipetting tip adapter and a switch attached to said tip adapter to detect the presence of pipetting tips on said pipetting tip adapter, comprising a first support member and a second support member configured to slide relative to one another between first and second positions along a movement axis when a pipetting tip is mounted on or detached from said pipetting tip adapter, characterized in that - the switch is a slide switch comprising: - an electrically conducting contact pad arranged on said first support member, and - the first position of said support members (21,22) defined by an electrically conducting terminal physically attached to said second support member and in physical contact with said contact pad, whereas - said terminal is a first resilient and inherently stable wiping member expanding along said movement axis, - and the second position of said support members (21,22) is defined when said first wiping member is not in physical contact with said contact pad, - and an electric current can flow between said first wiping member and said contact pad when said support members (21,22) are in the first position, and said electric current between said wiping member and said contact pad is disrupted when said support members (21,22) are in the second position, whereas - said electric current flows in an electrical single circuit comprising said contact pad, said first wiping member, an electrical power supply and an electrical unit. a pipetting tip adapter and a switch attached to said tip adapter to detect the presence of pipetting tips on said pipetting tip adapter, comprising a first support member and a second support member configured to slide relative to one another between first and second positions along a movement axis when a pipetting tip is mounted on or detached from said pipetting tip adapter, characterized in that - the switch is a slide switch comprising: - an electrically conducting contact pad arranged on said first support member, and - the first position of said support members (21,22) defined by an electrically conducting terminal physically attached to said second support member and in physical contact with said contact pad, whereas - said terminal is a first resilient and inherently stable wiping member expanding along said movement axis, - and the second position of said support members (21,22) is defined when said first wiping member is not in physical contact with said contact pad, - and an electric current can flow between said first wiping member and said contact pad when said support members (21,22) are in the first position, and said electric current between said wiping member and said contact pad is disrupted when said support members (21,22) are in the second position, whereas - said electric current flows in an electrical single circuit comprising said contact pad, said first wiping member, an electrical power supply and an electrical unit. - the switch is a slide switch comprising: - an electrically conducting contact pad arranged on said first support member, and - the first position of said support members (21,22) defined by an electrically conducting terminal physically attached to said second support member and in physical contact with said contact pad, whereas - said terminal is a first resilient and inherently stable wiping member expanding along said movement axis, - and the second position of said support members (21,22) is defined when said first wiping member is not in physical contact with said contact pad, - and an electric current can flow between said first wiping member and said contact pad when said support members (21,22) are in the first position, and said electric current between said wiping member and said contact pad is disrupted when said support members (21,22) are in the second position, whereas - said electric current flows in an electrical single circuit comprising said contact pad, said first wiping member, an electrical power supply and an electrical unit.