substitution request - Alliance Construction Solutions

3. Motor insulation shall be an “Inverter Grade” system designed to meet the voltage
spike limits defined by NEMA MG-1. Insulation systems shall use triple layer
magnet or shall use magnet wire which has a Pulse Endurance Index (PEI) greater
than 50. Insulation systems utilizing heavy film and two-film wire with a Pulse
Endurance Index less than 50 are not acceptable. Complete insulation of the slot,
cell, and phase groups is required. The system shall be rated for Class F
temperature rise or better.
4. Inverter Duty stator core designs shall be of high rigidity type with reinforced end
turn construction to minimize mechanical fatigue of the winding, and to reduce
resonant noise. Single dip and bake cycles are not acceptable.
5. Motor manufacturer shall supply certification with submittals that the motor is
constructed to meet all requirements of NEMA MG-1.
6. Rotor cores and/or assemblies shall be of a low vibration design that meets 1/2 of
the NEMA MG-1 recommended levels for balance.
7. Inverter duty motors shall include a normally closed winding over temperature
thermostat suitable to be wired to the VFD panel for drive shutdown.
8. Motor Selection Criteria:
Project No.: 10145
550 15 th Street Dual Brand Hotel
03/16/2012
a. Torque characteristics shall be sufficient to satisfactorily accelerate the
driven loads.
b. Motor sizes shall be large enough so that the driven loads will not require
the motor to operate in the service factor range. Minimum horsepower
ratings are shown or scheduled on the drawings.
c. Motors shall be selected so that operating limits (temperature rise, service
factor, etc.) are not exceeded at operating altitude and rated load.
9. Pump motors shall be “non-overloading,” i.e., shall not operate within service
factor range at any point on pump curve.
10. Provide reduced voltage starting for motors 25 HP and larger or when required by
local regulations, except when motor is controlled by a VFD. Maximum allowable
in-rush current shall not exceed 300% of motor full load amps unless specified
otherwise.
11. Power Factor Correction: (Disregard this item if motor is controlled by VFD.)
2.03 DISCONNECT SWITCHES:
a. Capacitors shall be installed on all motors 25 HP and larger that have an
uncorrected power factor of less than 90% at rated load. KVAR size shall
be as required to correct motor power factor to 95% lagging.
b. Capacitors shall have:
i. Individual unit cells.
ii. All welded steel housings.
iii. Non-flammable synthetic liquid impregnant.
iv. Craft tissue insulation.
v. Aluminum foil electrodes.
c. Each capacitor shall be internally fused.
A. See Division 26 for requirements.
B. Provide safety disconnect switches for all mechanical equipment unless specifically shown
on Division 26 requirements.
23 0513 - 5 MECHANICAL/ELECTRICAL REQ.
FOR MECHANICAL EQUIPMENT