In-Situ Wound Current Transformer Core

A method comprising:

• attaching a first flange to a first end of a first tube defining a first longitudinal axis;
• sliding a second tube over the first tube, the second tube defining a second longitudinal axis, the second longitudinal axis arranged substantially coincident with the first longitudinal axis;
• attaching a second flange to a second end of the first tube opposite of the first end of the first tube, wherein the first tube, the first flange, and the second flange collectively form a first bobbin defining a first slit along the first longitudinal axis, the first slit configured to allow receipt of a primary conductor into the first tube, and the second tube forms a second bobbin configured to rotate relative to the first bobbin, the second bobbin defining a second slit along the second longitudinal axis, the second slit configured to allow receipt of the primary conductor into the first tube and the second tube;
• and
• winding a secondary winding about the first bobbin, the secondary winding extending along the first longitudinal axis, passing through the first tube and over the first and second flanges.

A method of installing a current transformer, the method comprising:

• disposing a first bobbin on an electric line, the first bobbin comprising:
• a first tube having first and second ends and defining a first longitudinal axis;
• a first flange disposed on the first end of the first tube;
• a second flange disposed on the second end of the first tube, wherein the first tube, the first flange, and the second flange collectively define a first slit along the first longitudinal axis, the first slit configured to allow receipt of a primary conductor into the first tube;
• and
• a secondary winding wound about the first bobbin, the secondary winding extending along the first longitudinal axis, passing through the first tube and over the first and second flanges;
• disposing a second bobbin on the first bobbin, the second bobbin comprising:
• a second tube having first and second ends, the second tube defining:
• a second longitudinal axis;
• and
• a second slit along the second longitudinal axis, the second slit configured to receive the first tube into the second tube, wherein when the first tube is received into the second tube, the first longitudinal axis is substantially coincident with the second longitudinal axis and the second bobbin can spin about the second longitudinal axis relative to the first bobbin;
• and
• winding a core wrap about the second bobbin in a direction substantially perpendicular to the second longitudinal axis by rotating the second bobbin relative to the first bobbin while feeding the primary conductor onto the second bobbin.

A foil dispenser for wrapping foil onto a bobbin, the foil dispenser comprising:

• a dispenser body defining a rotation limiter configured to engage and limit rotation of a first bobbin, the first bobbin comprising:
• a first tube having first and second ends and defining a first longitudinal axis;
• a first flange disposed on the first end of the first tube;
• and
• a second flange disposed on the second end of the first tube;
• a bobbin drive configured to engage and rotate a second bobbin relative to the first bobbin, the second bobbin comprising a second tube rotatably received about the first tube, the second tube defining a second longitudinal axis substantially coincident with the first longitudinal axis;
• a supply reel rotatably supported by the dispenser body and configured to carry a wrapping of foil;
• and
• a clutch coupled to the supply reel and configured to resist rotation of the supply reel.