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Diagnostics
PMC Status - Veeder-Root Polisher
Figure 69. PMC Status Diagnostic Screen (Scroll Down to View Additional Fields)
AUTOMATIC MODE
If PMC mode is in AUTOMATIC, PMC will control flow through the Vapor Polisher using its vapor control valve.
The control algorithms will monitor tank pressure, vapor temperature and carbon temperature to monitor carbon
canister loading. Typically the valve opens to relieve the pressure and begin loading the canister. When the UST
pressure becomes negative the valve opens and the purging process begins. The valve closes when the canister
either reaches capacity or is empty after purging.
MANUAL MODE
If PMC mode is in MANUAL, touch the
Actions
button to manually set the valve to be opened (Set Requested:
OPEN) or closed ((Set Requested: CLOSED). This feature tests the operation of the valve without waiting for the
Vapor Polisher to reach loading or purging thresholds. It also provides the necessary controls to perform 2" decay
tests. The current UST ullage space vapor pressure is available in this screen.
When set to Manual mode, the system will reset to Automatic mode after 4 hours.
SWITCHING BETWEEN VAPOR PROCESSOR MODES
With the Vapor Polisher Mode in Automatic, touch the
Actions
button to switch the PMC Mode to Manual (see
Figure 70), or when in Manual Mode, touch the
Actions
button to set the vapor valve Open or Closed and /or
touch ‘Set VP Mode: Automatic’ to exit Manual Mode.
