Operating instructions

Entering Geographical
Latitude, Local Elevation
and Acceleration of Gravity
Purpose
To perform an external adjustment of
the weighing instrument at a place of
adjustment that is not the same as the
place of installation.
When a weighing instrument changes
location and is used somewhere else, its
sensitivity changes as well. The sensitiv-
ity is dependent on the acceleration of
the earth's gravity, which in turn is
affected by the geographical latitude
and the elevation of the place of instal-
lation. In general, the acceleration of
gravity increases in the direction of the
poles (i.e. with increasing degree of
latitude) and decreases the greater the
distance is from the center of the earth
(i.e. with increasing elevation).
If the precise location of the place of
installation is known; i.e. its geographi-
cal latitude in degrees (northern or
southern latitude) and the elevation
in meters above sea level, then the
weighing instrument can be adjusted
at the factory in preparation for its
future place of installation, provided
that the geographical latitude and
elevation
at the place of adjustment
are also known. Rather than the
geographical latitudes and local
elevations of the places of adjustment
and installation, it is sufficient to
know the acceleration of gravity at
both the places.
The following data, describing the place
of manufacture (Sartorius in Goettingen,
Weender Landstrasse 94-108) is used as
reference data:
– Geographical latitude:
51° 32’ = 51.53 degrees
– Elevation: 151 m
– Acceleration of gravity: 9.811590 m/s
-2
If this reference data is stored in the
indicator, the adjustment factor does
not need to be corrected for the place
of installation.
After closing the menu access switch,
the geographical data is stored in the
A/D converter.
The tolerance zones, e.g. for a scale
with 3000 e, are ± 100 km for the
latitude and ± 200 m for the elevation
above sea level.
The following exception applies in
Germany for scales with 3000 e:
If the latitude is set to 51,00° and the
altitude 513 m above sea level, which cor-
responds to an acceleration of gravity of
9.810 m/s
-2
, then the scale can be used
anywhere in Germany (“Zone D”).
These values are calculated for Germany
based on a mean value for the Earth’s
acceleration. The greater the precision of
the geographical data entered, the greater
the precision achieved with the weighing
instrument; the tolerance range, however,
is also restricted accordingly (see above).
Procedure
The geographical data stored in the
indicator at the factory applies to Germany
(“Zone D”) (see above).
Before adjusting the complete weighing
system, make sure the geographical
reference data stored in the indicator
matches the values for the place of adjust-
ment (whether at the factory or at the
place of installation). If the values do not
match, enter the latitude and elevation
under menu items 1-20-1 and 1-20-2,
or the acceleration of gravity under item
1-20-3. Then adjust the scale. If the place
of adjustment is not the same as the place
of use, enter the data describing the place
of use. Following adjustment, close the
menu access switch. The scale can now be
used at the place of installation, or any-
where within a tolerance zone (see above)
around the place of installation. If the scale
is installed in Germany, you can enter the
data for “Zone D” (51,00 degrees,
513 m above sea level). In this case,
the scale can be used anywhere within
Germany. This setting is recommended for
weighing equipment dealers who do not
need to know the exact geographical data
when delivering to customers in Germany.
If a service technician performs a span
adjustment (for example after one or more
load cells have been replaced), it is con-
ducted without changing the values stored
in the menu items 1-20-1 and 1-20-2,
or 1-20-3.
For this adjustment, either the geographi-
cal latitude and elevation (menu items
1-20-1 and 1-20-2) or the acceleration
of gravity (menu item 1-20-3) for the place
of installation must be entered. This data
can be obtained from the relevant Cadaster
Agency or the State Surveying Authorities.
The geographical data cannot be edited
unless the menu access switch is open.
If the indicator is part of a verified weigh-
ing system, the verification seal must be
broken to change this data. Afterwards, the
scale must be re-verified.
If the acceleration of gravity has been
entered, then this value takes precedence
over the geographical latitude and the
elevation. When the menu item 1-20-1
is called up, the value “99999.99" is
displayed; when the menu item 1-20-2
is called up, the value “9999999" is dis-
played. In the converse case (geographical
latitude and local elevation were entered),
the value “0.000000" is displayed for the
menu item 1-20-3.
To display geographical data during the
adjustment procedure, select menu item
8-12-2 (factory setting: 8-12-1; “Do not
show geographical data”). With this setting
active, the indicator shows which set of
data is used for adjustment; either the lati-
tude and elevation or the acceleration of
gravity. Press ) to confirm the data
shown; or, if the data is invalid, press (
to cancel the adjustment routine.
If the display of geographical data (menu
item 18-12-2) is active, the adjustment
procedure is as follows:
After starting the adjustment procedure
“CAL" and when the data “local elevation"
and “geographical latitude" is used, the
word “ALTITUD" appears for 2 seconds,
followed by the settings for the elevation
(in meters above sea level). Press ) to
confirm the data, or ( to cancel the
adjustment routine. Then, the word
“LONGITUD" appears for 2 seconds, fol-
lowed by the settings for the geographical
latitude in degrees. Press ) to confirm
the data, or ( to cancel the adjustment
routine. After this, the prompt to place
the adjustment weight appears. If, instead
of elevation and geographical latitude,
the acceleration of gravity was entered,
the word “GRAVITY” appears for 2 seconds
after “CAL," followed by settings for the
value for the acceleration of gravity.
Press ) to confirm the data, or ( to
cancel the adjustment routine.
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