OHAUS 700 Series, Руководство по обслуживанию на месте

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3-1
CHAPTER 3 SERVICING
3.1 SERVICE OF SERIES 700 TRIPLE BEAM
Refer to Figure 5-1 in Section 5 for identification of parts.
NOTE: Non-removable Knife Edges, you must replace the Beam
A. Non-Repeatability
Problem: Damper Vane touching the end of Trig Loop
Solution: Loosen the screw holding Trig Loop to Base and move it back.
Problem: Bent Damper Vane that is making contact with magnets in Trig Post
Assembly
Solution: Bend Vane with fingers or needle nose pliers (hold Beam down when
performing this operation) or remove the Trig Loop, remove the Vane and hammer
straight.
Problem: Dull Knives
Solution: To check Knives, hold Beam down. Does it return to zero? Hold Beam
up. Does it return to zero? If not, replace the Beam. This may also indicate chipped
Knife Edges.
B. Can Not Zero Balance
Problem: Missing Poise (This is the Weight that slides on the Beam.)
Solution: Replace new Poise and secure by forcing Check Pin up with a pair of
needle nose pliers. (The 100g Poise has the Check Pin, the 500g Poise does not.)
Problem: Shot Missing from under Pan.
Solution: Set Zero Adjustment at mid point of travel. Set all Poises at zero. Unscrew
the Balance Pan and place it upside down on the Balance. Add lead shot or pieces
of metal to bring Balance close to zero. Transfer shot to Balance Cup and
reassemble Balance Pan.
Problem: Chipped Knife Edge: (or dull worn Bearing [notches]). To check, pry off
Bearing Covers (these will have to be replaced by new ones). Remove Friction
Plates and lift out the Beam.
Solution: If Knife Edges are chipped or worn, replace the Beam. If Bearings are
worn, slide them up and replace with new Bearings. (NOTE: Balance that does not
have repeatability is also a symptom of worn bearings).
C. No Beam Movement
Problem: Twisted Beam or Vane rubbing.
Solution: Refer to Section A.
Problem: Foreign Material on Magnets.
Solution: Remove with adhesive backed tape or remove Trig Loop and clean
magnets.