8
Figure 2
6
、
Function description
After connecting the gas circuit, you can open the valve on the gas
cylinder, turn on the power supply of the instrument, and enter the main
interface after system initialization, as shown in Figure 3, which has the
functions of " Density relay ", " Normal Pressure ", "20
℃
Pressure ", " History
Record ", " Date Setting ", " PC Comm.",etc. Rotate the mouse left and right,
the cursor can switch freely before each function item, select the function item,
and click Select to enter.
Figure 3
6.1 Verify SF6 density relay
Basic principle of SF6 density relay calibration: the gas pressure in the closed
vessel changes with the change of temperature, and the relative pressure value of
SF6 at 20
℃
is usually taken as the standard value. In the field calibration,the SF6
pressure value measured at a certain ambient temperature shall be converted to
the equivalent pressure value at 20
℃
, so as to judge the performance of the
density relay.
Verification of latching reply value:
At the ambient temperature, when
the SF6 density relay is at zero pressure, slowly inflate the SF6 density relay at
a certain speed. When the locking relay of the SF6 density relay acts, record
the pressure value under the current ambient temperature, and convert it into