Schreiber Chillers Old 4 ton MRI - Manual (Page 20)

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2. Installation
Installation, Operation and
Maintenance Instructions.
Model NPE/NPE-F
DESCRIPTION & SPECIFICATIONS:
The models NPE (close-coupled) and NPE-F (frame-
mounted) are end suction, single stage centrifugal
pumps for general liquid transfer service, booster
applications, etc. Liquid-end construction is all AISI Type
304 stainless steel, stamped and welded. Impellers are
fully enclosed, non-trimable to immediate diameters.
Casings are fitted with a diffuser for efficiency and for
negligible radial shaft loading.
Close-coupled units have NEMA 48J or 56J
motors with C-face mounting and threaded shaft
extension. Frame-mounted units can be coupled to
motors through a spacer coupling, or belt driven.
1.1. Inspect unit for damage. Report any damage to
carrier/dealer immediately.
1.2. Electrical supply must be a separate branch circuit
with fuses or circuit breakers, wire sizes, etc., per
National and local electrical codes. Install an all-leg
disconnect switch near pump.
CAUTION
Always disconnect electrical power when handling pump
of controls.
1.3. Motors must be wired for proper voltage. Motor
wiring diagram is on motor nameplate. Wire size must
limit maximum voltage drop to 10% of nameplate voltage
at motor terminals, or motor life and pump performance
will be lowered.
1.4. Always use horsepower-rated switches, contactor
and starters.
1.5. Motor Protection
1.5.1. Single-phase: Thermal protection for
single-phase units is sometimes built in (check
nameplate). If no built-in protection is provided,
use a contactor with a proper overload. Fusing
is permissible.
1.5.2. Three-phase: Provide three-leg protection
with properly sized magnetic starter and thermal
overloads.
1.6. Maximum Operating Limits:
Liquid Temperature: 212F (100C) with standard seal.
250F (120C) with optional high
temp seal.
Pressure: 75 PSI.
Starts Per Hour: 20, evenly distributed.
1.7 Regular inspection and maintenance will increase
service life. Base schedule on operating time. Refer to
section 8.
2.1. General
2.1.1. Locate pump as near liquid source as
possible (below level of liquid for automatic
operation).
2.1.2. Protect from freezing or flooding.
2.1.3. Allow adequate space for servicing and
ventilation.
2.1.4. All piping must be supported
independently of the pump, and must “line-up”
naturally.
CAUTION
Never draw piping into place by forcing the pump suction
and discharge connections.
2.1.5. Avoid unnecessary fittings. Select sizes to
keep friction losses to a minimum.
2.2. Close-Coupled Units:
2.2.1. Units may be installed horizontally,
inclined or vertically.
CAUTION
Do not install with motor below pump. Any leakage or
condensation will affect the motor.
2.2.2. Foundation must be flat and substantial to
eliminate strain when tightening bolts. Use rubber
mounts to minimize noise and vibration.
2.2.3. Tighten motor hold-down bolts before connecting
piping to pump.
2.3. Frame-Mounted Units:
2.3.1. Bedplate must be grouted to a foundation with
solid footing. Refer to Fig. 1.
1. Important
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