Fig. 5.1
REF. 506 0042
Fig. 5.0
Fig. 5.2
OMEGA SA
WORLD SERVICE ORGANIZATION
GT-19-C-006-E - D - 2628
/18
Special parameter settings
Instrument type
Co-Axial
4 Hz calibres
Co-Axial
3.5 Hz calibres
Comments
Former Witschi instruments
- Watch Expert (red case)
- Wicometer Professional
- Chronoscope M1 (old version)
Lift angle
set to 30°
Lift angle
set to 38°
3.5 Hz calibres:
The frequency parameters
(25’200 A/h) should be
set manually so that the
instantaneous rate is
All measurements
are correct
The amplitude
is not measured
correctly
New Witschi instruments
- Watch Expert II (white case)
- Chronoscope M1 (up-dated version)
- Chronoscope S1
Lift angle
set to 38°
Lift angle
set to 38°
Test mode:
Parameters must be set
for «Spe1»!
All measurements
are correct
All measurements
are correct
5.0 Timing key
A special timing key tool has been developed to adjust
the rate even when the movement is cased in. The rate
can be corrected according to the table below by turning
the two balance screws a complete turn. A scale is found
on the outside of the tool. A division corresponds to a rate
correction of 1 second. (according to the table below).
One screw is located between two arms on the balance
which are specially marked by points (see Figure 5.2) for
easy identification of each screw during the correction
process.
Balance
The annular balance has two adjusting micro-screws. A
slow rate deviation is corrected by tightening the micro-
screws (towards the centre of the balance), which redu-
ces its moment of inertia and makes it run faster. A fast
rate deviation is corrected by loosening the micro-screws
(away from the centre of the balance). This increases its
moment of inertia and makes it run slower.
Important:
The rate is always corrected using
both adjustment
screws
to prevent an unbalance of the balance.
Demagnetise the movement according to Working
Instruction 34.
Values to be checked
Please consult Working Instructions 5 and 28 for
instructions and tolerances.
Version A
Version B
One correction turn = 57 seconds
One correction turn = 86 seconds
One division = 1 second
One division = 1.5 seconds
Speci
fi
c information for Calibre 2628
