Ohaus 311 CENT-O-GRAM BALANCE Manual - Manual (Page 7)

7
SPECIFIC GRAVITY DETERMINATIONS
(Continued)
The specimen can then be suspended from a fine wire or thread from the lower
hook of the end loop into a beaker or other suitable container of water or other
liquid.
SOLIDS - (denser than water)
To determine specific gravity of solids denser than water, the specimen should be
first weighed in air and then weighed immersed in water.
S. G. = Weight in air
Weight in air minus weight in water
SOLIDS - (less dense than water)
To determine the specific gravity of solids less dense than water, it is necessary
to attach a sinker and then make the following weighings:
a. Weight of body in air.
b. Combined weight of body in air plus sinker in water .
c. Weight of both body and sinker in water.
Specific Gravity = a a
b – c
CARE AND MAINTENANCE
With reasonable care, your Balance can be kept in good working order. Keep it
clean and do not drop it. Foreign matter can be most easily removed with an air
syringe. When the balance is not used, it should be protected by a balance cover.
(Part No. 110). Never apply oil or any lubricant to the knife edges or bearings;
this will lower the accuracy of the balance. From time to time, it may be
necessary to clean the damping magnet faces. This is best done by inserting a
piece of adhesive-backed tape into the damper vane slot (right side of beam),
and pressing it against the magnet face. The tape will pick up foreign material
and prevent it from interfering with movement of the damper vane.
OPTIONAL ACCESSORIES
Description Model No. Item No
Balance Cover 110-0 80780005
Test Tube Kit 76912-01 80780018
SERVICE INFORMATION
For service assistance in the USA, please call Ohaus Corporation toll-free at
(800) 526-0659. An Ohaus Product Service Specialist will be available to help
you.