. A Duplex Fuel Supply System (427 series) adds an additional pumping sub-
. system to the first pump and motor that is installed on a day tank, sub-base tank,
. remote pumping unit, or other platform. A duplex system provides:
. * Redundant Back-up,
. * Greater Pumping Capacity (in case a single pump cannot keep up with the
. demands of in-tank fuel draw down,
. * Configuration Flexibility, and
. * Reduction of run time (in the case of 427A and 427B) of the first installed
. sub-system.
. The three duplex systems described here have at least one thing in common,
. each have a "LEAD" pumping sub-system and a "LAG" pumping sub-system.
. * The LEAD is always the one that is activated first when fuel is required from
. the main storage tank, and
. * The LAG is next if the lead cannot keep up with the demand.
. NOTE - Option #427 "hard" assigns the LEAD to the first pumping sub-systems
. (physically the bottom in the stacking arrangement) and the LAG to the second
. (the top pump/motor).
. Options 427A and 427B switch the pumping sub-systems "logically" into a soft,
. or temporary, Lead/Lag assignment. 427A does this automatically and 427B is
. manual switching (see below).
|
|
|
|
DUPLEX (Second Standard) PUMP and MOTOR ASSEMBLY
A second 2 GPM pump, a Thermal Protected motor (1/3 HP, 115vac, 1
PH, 60 Hz) and a second float switch.
The first pump-motor (always the “lead”) begins operating at 86% of
usable fuel capacity; the second pump-motor (always the “lag”) begins
operating to assist the lead pump when fuel drops to 82% of usable
fuel capacity. Both pump-motors shut off at 100% capacity.
|
|
|
|
AUTOMATIC TRANSFER SWITCH
A switching system to automatically alternate each pump-motor (of
option #427) into the lead starting position. (At the 82% and lower
levels, both will operate.) Includes: Option # 427, a pump “RUN-OFF-
AUTO” mode selector switch, and a “Pump Running” amber light for
each pump-motor
|
|
|
|
MANUAL TRANSFER SWITCH
A switching system to manually alternate each pump-motor (of option
427) into the lead starting position. (At the 82% and lower levels, both
will operate.)Includes: Option #427, a manual transfer switch, and a
motor run-time meter included for each pump-motor.
|
|
