... steel, protective layer thickness, reinforcement spacing, bar diameter, and can accurately draw the overall reinforcement ... reinforcing bars, steel cover thickness and diameter, also has: 1 grid measurement, continuous scanning in both directions, ... 6-φ50;-Protective layer measurement accuracy :6-79mm, error ≤ ± 1mm; 80-119mm, error ≤ ± 2mm; 120-190mm, error ≤ ± 4mm;-Bar diameter measurement accuracy: ...