GHM Delta OHM HD2328.0, Руководство по эксплуатации

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HD2328
- 10 -
V1.7
PROBES AND MEASUREMENTS
The instrument works with thermocouple probes of type K, J, T, or E.
See chapter ‘The programming menu’ for the selection of the type of probe.
The contacts of the thermocouple probe connector are polarized. They must be
inserted on the standard miniature socket located on the instrument in the correct
direction. These probes are usually marked with a "+" and "–" sign.
The user can choose the unit of measurement for display of temperature: °C and °F.
The Thermometer HD2328.0 has two inputs: the temperature for input "A" (see
description of the inputs) is displayed in the main line: the temperature for input "B"
is displayed in the secondary line. When the "A-B" function is enabled, the relevant
differential temperature is displayed in the secondary line.
If two probes are used, they must be the same type of thermocouple.
T
EMPERATURE
M
EASUREMENT
In all versions the thermocouple hot junction is housed in the end part of the probe.
The response time for the measurement of the temperature in air is greatly reduced if
the air is moving. If the air is still, stir the probe. The response times are longer than
those for liquid measurements.
The temperature measured by immersion is carried out by inserting the probe in the
liquid, in the oven where you wish to perform the measurement; the hot junction is
housed in the end part of the probe.
In the temperature measured by penetration the probe tip must be inserted into the
material; the hot junction is housed in the end part of the probe.
NOTE: when measuring the temperature on frozen blocks it is convenient to use a
mechanical tool to bore a cavity in which to insert the tip probe.
In order to perform a correct contact measurement, the measurement surface must
be even and smooth, and the probe must be perpendicular to the measurement plane.
So as to obtain the correct measurement, the insertion of a drop of oil or
heat-conductive paste between the surface and the probe is useful (do not
use water or solvents). This method also improves the response time.
C
ALIBRATION OF THE INSTRUMENT ON LINE WITH THE PROBE
(
S
)
To calibrate the probes correctly, a knowledge of and abiding by the physical
phenomena on which the measurement is based is fundamental: this is the reason
why it is recommended to abide by what is reported below carefully, and only to
perform new calibrations if technically proficient and using the suitable equipment.
The instrument is provided with the only FACT (factory) calibration.
The user is also able to perform a USER calibration of insprobe.