vacuubrand ME 4C VARIO select, Инструкция по эксплуатации

Страница: 48 / 76

page 48 of 76
The device was adjusted using factory standards, which
are traceable through regular calibration in an accredited
laboratory (DAkkS calibration laboratory) to the German
national pressure standard. Depending on the process
and/or accuracy requirements, check the adjustment and
readjust if necessary. For readjustment, the device has to
be adjusted both at atmospheric pressure as well as un-
der vacuum but only if the reference pressures are known
with certainty. In the range between 15 to 525 Torr (20 to
700 mbar) no adjustment is possible.
Adjustment at atmospheric pressure
An adjustment at atmospheric pressure is only possible if
the pressure is higher than 525 Torr (700 mbar).
Vent the measurement connection of the vacuum sensor
(e.g., VACUU•SELECT Sensor) and/or the vacuum sys-
tem. Make sure that the measurement connection of the
vacuum sensor is at atmospheric pressure.
Note
: To determine the actual atmospheric pressure,
use an accurate barometer or get accurate reading from
the weather service, or a nearby airport or other reliable
source (taking into account the difference in altitude be -
tween the source and the laboratory).
Adjustment under vacuum or at a reference pressure
An adjustment under vacuum is only possible if the pres-
sure is lower than 15 Torr (20 mbar) absolute.
Evacuate the measurement connection of the vacuum
sensor to a pressure < 0.1 Torr (mbar) (e.g., by applying a
good two-stage rotary vane pump).
Readjustment of vacuum sensor