Laser Plummet (Optional); Instrument Constant (K) - Horizon Fitness HTS-580 Series Operation Manual

12.8 Laser Plummet
A laser plummet tribrach may be ourchased separately for the instruments.

12.9 Instrument Constant (K)

The instrument constant has been checked and adjusted in the factor, K=0. It
changes seldom and it is suggested to check one or two times every year. The
inspection should be made on a base line but also can be made according to the
following method.
Inspection
1. Mount and level the instrument on Point A in a flat area. Use the vertical hair
to mark Point B and Point C on the same line with the distance of 50m between each
point. Set the reflector accurately on each point when measuring.
2. After setting temperature and air pressure in the instrument measure the
Horizontal Distance of AB and AC accurately.
3. Set the instrument on Point B and center it accurately, measure the
Horizontal Distance of BC accurately.
4. Then you can calculate the Instrument Constant:
K should be very close to 0, If | K | > 5 mm the instrument should be inspected
at a standard baseline site and adjusted according the inspection value.
K=AC-(AB+BC)
239