Building electrical BV wire pay-off device

The utility model belongs to the field of cable pay-off equipment, and particularly relates to a building electrical BV cable pay-off device which comprises a case, a pay-off roller, a motor, a pressing mechanism and a limiting mechanism. A pressing mechanism is fixed to the bottom end of the interior of the machine box, a pay-off roller is rotationally arranged above the pressing mechanism, a supporting plate is installed on one side of the machine box, a motor is slidably arranged on the supporting plate, U-shaped grooves are formed in the upper portions of the two sides of the machine box, limiting blocks are arranged at the bottoms of the U-shaped grooves, and a measuring instrument is fixed to the lower portions of the U-shaped grooves. By arranging the pressing mechanism and the measuring instrument, when a BV wire is paid off, a pay-off roller is placed into the machine box through a U-shaped groove, the BV wire is drawn out from a pay-off hole formed in the front face of the machine box, and when pay-