Specifications - State of Delaware

SECTION 262900 - MOTOR CONTROLLERS, CONTACTORS, PUSH BUTTONS, SELECTOR
SWITCHES, INDICATING LIGHTS AND RELAYS: continued
characteristics of the controller, motor and load furnished to provide proper protection by the
main protective device, without nuisance tripping. Provide operating handle for main circuit
protective mechanism with indication and control of position, with enclosure door either open
or closed and capable of being locked in "OFF" position with three padlocks. Construct
controller with NEMA Type 1 enclosure for indoor, dry, nonhazardous locations. Coat with
manufacturer's standard color finish.
F. Combination Disconnect and Wye-Delta Controllers: Provide wye-delta controllers, of sizes,
ratings, electrical characteristics, and NEMA sizes indicated or required. Provide integral main
thermal magnetic circuit breaker or main motor circuit protector. Manufacturer shall size and
coordinate the main protective device with the characteristics of the controller, motor and load
furnished to provide proper protection by the main protective device, without nuisance
tripping. Construct controllers with open-circuit transition, including three pole thermal
overload protection relay, fused 120V control transformer, push buttons, selector switches, and
indicating lights. Equip with START-STOP push button for control. Provide controller with
electrical interlocks specified and as required. Provide two normally open and two normally
closed spare auxiliary contacts. Provide operating handle for disconnect main circuit
protective mechanism with indication and control of position, with enclosure door either open
or closed, and capable of being locked in "OFF" position with three padlocks. Construct
controller with NEMA Type 1 enclosure for indoor, dry, nonhazardous locations. Coat with
manufacturer's standard color finish.
G. Combination Disconnect and Part Winding Controllers: Provide two-step, part-winding,
alternating-current controllers, of NEMA sizes, ratings, and electrical characteristics indicated
or required, suitable for use with motors with two wye-connected windings. Provide integral
main thermal magnetic circuit breaker or main motor circuit protector. Manufacturer shall size
and coordinate the main protective device with the characteristics of the controller, motor and
load furnished to provide proper protection by the main protective device, without nuisance
tripping. Controller shall have two 3-pole contactors, pneumatic timer, fused 120V control
transformer, push buttons, selector switches, indicating lights, and two 3-pole manual external
reset motor overload relays. Provide controller with electrical interlocks specified and as
required. Provide two normally open and two normally closed spare auxiliary contacts.
Provide operating handle for main circuit protective mechanism with indication and control of
position, with enclosure door either open or closed and capable of being locked in "OFF"
position with three padlocks. Enclose controller unit in NEMA Type 1 general purpose
enclosure for indoor, dry, nonhazardous locations. Coat enclosure with manufacturer's
standard color finish.
H. Combination Disconnect and Solid-State, Variable Frequency Drives (VFDs): Provide solidstate
speed adjustment with adjustable frequency and voltage output that shall provide constant
volts per hertz excitation of a three-phase, squirrel-cage induction motor up to 60 Hz. The
controller shall have a 100% overload rating for one minute. The controller shall have a
minimum efficiency of 95% at rated load. The controller shall operate in an ambient
temperature of -10ºC to 50ºC for elevations up to 3,300 feet above sea level and within a
humidity range of 0 to 95% noncondensing. The variable torque controller starting current
shall be limited to 150% of the full load current.
1. Enclosures shall be NEMA Type 1 for indoor, dry, nonhazardous locations. Provide wall
mounted enclosures for control of motors smaller than 75 horsepower and free standing
enclosures (with lifting eyes and enclosure suitable for pushing and being moved on
rollers) for control of motors 75 horsepower and larger. Coat enclosure with
manufacturer's standard color finish.
262900-4 DEAN262900.DOC