Bartec APEXpy 07-37A2-2111/ 520Series Operating Instructions Manual page 76

Ex p Control unit
APEX py
Rev. 0
Ex p control with application proportional purge gas valve
When using a proportional purge gas valve, the achieved purge pressure p3 is
achieved by adjusting the internal pressure to the value 7/8 of p5.
This means that the internal pressure can be finely adjusted during purging
with the aid of the proportional valve, which can be advantageous for
pressure-sensitive assemblies in the front of the pressurized equipment.
Procedure
 Connect PC with Ex p control unit, activate programming switch
 Login to the WEB interface with the user level
 Call up the Purge parameter / Pressure parameter menu
 Pressure parameter p3 - set purge pressure to 2000 Pa (20 mbar)

Pop-up window with display of changed value appears, Confirm
 Pressure parameter p5 - maximum pressure, purge set to the value,
which the pressurized equipment is allowed during purging, e.g. set 2000
Pa (20 mbar).

Pop-up window with display of changed value appears, Confirm
During the purging phase, the Ex p control unit regulates to the
internal pressure to 7/8 of p5 when a proportional valve is used.

Means that with this setting, the internal pressure during the purging
phase is 17.5 mbar. If 20 mbar is exceeded during the purging phase,
the purging gas valve is closed. The further behavior depends on the
setting of the purge mode.
 Deactivate programming switch

Ex p Control unit changes from programming mode to
control/monitoring mode.
 Press the "F5" key of the PC to refresh the browser window.
 Start screen opens.
 Note the actual value of the p3 purge pressure, as example 10 mbar.
Operating instructions Chapter Opening the purge air diagram
Read out the corresponding flow rate Q as a function of the
determined p3 from the diagram. As example 15 000 l/h
Using the formula
t [min] = ((V [l] x factor purging) / Q [l/h]) x 60
2 min = ((100 l x 5 times purging) / 15000 l/h) x 60
 Pop-up window with display of changed value appears, Confirm
 Activate programming switch
 Login into the WEB interface with the user level
 Call up the Purge parameter / Pressure parameter menu
 Pressure parameter p3 - Set purge pressure to determined value

Pop-up window with display of changed value appears, Confirm
 Call up the Purge parameter / Purge mode menu
 Set the purge time to the calculated purge time

Pop-up window with display of changed value appears, Confirm
01-37A2-7D0006_py_Manual_Exp-Control-Unit_20210923_a_en.docx
Commissioning
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