Constant speed pumping system with pressure regulating valves shall employ
one lead pump for low flows, and one or more lag pumps for higher flows.
Pressure regulating valves shall be provided with nonslam check feature.
The factory prepiped and prewired assembly shall be mounted on a steel
frame complete with pumps, motors and automatic controls. The system
capacity and capacity of individual pumps shall be as indicated. Current
sensing relays shall provide staging of the pumps. The pumps shall be
protected from thermal buildup, when running at no-flow, by a common
thermal relief valve. Pressure gauges shall be mounted on the suction and
discharge headers. The control panel shall bear the UL listing label for
industrial control panels and shall be in a NEMA 250, Type 1 enclosure.
The control panel shall include the following: No-flow shutdown; 7-day
time clock; audio-visual alarm; external resets; manual alternation;
magnetic motor controllers; time delays; transformer; current relays;
"HAND-OFF-AUTOMATIC" switches for each pump; minimum run timers; low
suction pressure cutout; and indicating lights for power on, individual
motor overload, and low suction pressure. The control circuit shall be
interlocked so that failure of any controller shall energize the succeeding
controller.
2.16.2
Hydro-Pneumatic Water Pressure System
In addition to constant speed pumping system described above, an ASME code
constructed tank stamped for 862 kPa 125 psig water working pressure shall
be provided. Tank shall have a flexible diaphragm made of material
conforming to the Food and Drug Administration requirements for use with
potable water. Tank shall be factory precharged to meet required system
pressure.
2.16.3
Variable Speed Pumping System
Variable speed pumping system shall provide system pressure by varying
speed and number of operating pumps. The factory prepiped and prewired
assembly shall be mounted on a steel frame complete with pumps, variable
speed drives, motors, and controls. The variable speed drives shall be the
variable frequency type capable of power transmission throughout their
complete speed range without vibration, noise, or shock loading. Each
variable speed drive shall be run-tested by the manufacturer for rated
performance, and the manufacturer shall furnish written performance
certification. System shall have suppressors to prevent noise transmission
over electric feed lines. Required electrical control circuitry and system
function sensors shall be supplied by the variable speed manufacturer. The
primary power controls and magnetic motor controllers shall be installed in
[the controls supplied by the drive manufacturer] [the motor control
center]. The sensors shall be located in the system to control drive speed
as a function of [constant pump discharge pressure] [constant system
pressure at location indicated]. Connection between the sensors and the
variable speed drive controls shall be accomplished with [hydraulic sensing
lines] [copper wiring] [telemetry]. Controls shall be in NEMA 250, Type 1
enclosures.
2.17
COMPRESSED AIR SYSTEM
2.17.1
Air compressors shall conform to ASME B19.3. Medical (oil-free air)
compressor installation shall conform to NFPA 99. Air compressor unit
shall be a factory packaged assembly, including [_____]-phase, [_____]
SECTION 15405A
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