Ex p control unit
Motor purge controller
Operation
Rev. 0
01-37A2-7D0003_Operating instructions_MPC_20210923_0_en.docx
Page 57 of 96
The purge gas flow can be read from the diagram by using the determined
pressure “p3”. Diagrams are available in the Appendix.
Calculation of the pre-purge time by using the following formula:
𝑃𝑢𝑟𝑔𝑒 𝑡𝑖𝑚𝑒[𝑀𝑖𝑛] =
𝐻𝑜𝑢𝑠𝑖𝑛𝑔 𝑣𝑜𝑙𝑢𝑚𝑒 [𝐿𝑖𝑡𝑟𝑒] × 5[−𝑓𝑜𝑙𝑑 𝑝𝑢𝑟𝑔𝑖𝑛𝑔]
𝐹𝑙𝑜𝑤 𝑟𝑎𝑡𝑒 [
𝐿𝑖𝑡𝑟𝑒
𝐻𝑜𝑢𝑟
]
× 60
Connect the PC with the Ex p control unit
Activate the programming switch
Log into the WEB interface with the user level
Call up the purging parameters / purging modes menu
Enter the calculated purging time via the keyboard at “purging time” and
confirm with Enter.
e.g. 10 minutes 30 seconds
Confirm pop-up window with the changed value
Deactivate programming switch
Call up the Status menu
7.13.1.5
Flushing
DANGER
DEATH OR SERIOUS PERSONAL INJURY DUE TO AN INSUFFICIENT VOLUME
OF PURGE GAS
Danger to life due to unsafe condition.
The purge factor must not be set below the required purge factor.
When activating "Automatic" for purging the Ex p room, the purge factor must be
set.
The flushing of the volume specified in the “Enclosure parameters” tab is purged
through several times by this factor.
Example:
Stored enclosure volume = 100 litres
Stored flushing factor = 5
Resulting flow through the enclosure is equal to
Volume x factor = flow rate of purging gas
100 litres x 5 = 500 litres
