ERRORS IN PLANE TABLE SURVEYING

The errors can be grouped into the instrumental and personal errors two category.

Instrumental Errors

(a)   The surface of plane table not completely plane.

(b)   Bevelled edge of alidade not straight.

(c)    Sight vanes of alidade not completely perpendicular to the base.

(d)   Plane table clamp being loose.

(e)   Magnetic compass being sluggish.

(f)     Drawing sheet being of poor quality.

Personal Errors

(a)   Levelling errors

(b)   Centering errors

(c)    Sighting errors

(d)   Orientation errors

(e)   Plotting errors

(f)    Errors due to instability of tripod.