Specifications - State of Delaware

SECTION 262900 - MOTOR CONTROLLERS, CONTACTORS, PUSH BUTTONS, SELECTOR
SWITCHES, INDICATING LIGHTS AND RELAYS: continued
B. Combination Disconnect and Full Voltage Controllers: Provide full-voltage nonreversing
(FVNR) or full voltage reversing (FVR), alternating-current combination controllers,
consisting of controller, fused 120V control transformer, push buttons, selector switches,
indicating lights, nonfused disconnect switch mounted in common enclosure, of types, sizes,
ratings, and NEMA sizes indicated or required. Equip controller with electrical interlocks
specified and indicated. Provide controller with two normally open and two normally closed
spare auxiliary contacts. Equip controller with block type manual external reset three-phase
overload relay. Provide operating handle for disconnect mechanism with indication and
control of switch position, with enclosure door either opened or closed and capable of being
locked in "OFF" position with three padlocks. Construct and mount controllers and disconnect
mechanism in single NEMA Type 1 enclosure for indoor, dry, nonhazardous locations and
NEMA 3R for Hangar Bay and other wet locations. Coat with manufacturer's standard color
finish.
C. Fractional HP Manual Controllers: Provide single-phase, fractional HP manual motor
controllers, of sizes and ratings indicated. Equip with manually operated quick-make, quickbreak
toggle mechanisms; and with one-piece melting alloy type thermal units. Controller to
become inoperative when thermal unit is removed. Provide controllers with double break
silver alloy contacts, visible from both sides of controller; and switch capable of being
padlocked-OFF. Enclose controller unit in NEMA Type 1 general purpose enclosure for
indoor dry, nonhazardous locations suitable for flush or surface mounting (as indicated). Coat
with manufacturer's standard color finish. Provide green pilot light where indicated or
specified.
D. Combination Disconnect and Solid-State Reduced Voltage Controllers: Provide solid-state
reduced voltage controllers for use with 3-phase squirrel cage induction motors, of types, sizes,
ratings, and electrical characteristics indicated; construct with silicon-controller rectifiers
(SCRs) for controlling motor voltages during acceleration and three-pole thermal overload
relay. 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. Equip controllers with fused 120V control transformer,
push buttons, selector switches, indicating lights, and closed-loop feedback system to maintain
motor acceleration at constant rate. 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 in NEMA
Type 1 enclosure for indoor, dry, nonhazardous locations. Coat with manufacturer's standard
color finish.
E. Combination Disconnect and Automatic Autotransformer Reduced Voltage Controllers:
Provide autotransformer type reduced voltage controllers, of sizes, ratings, electrical
characteristics and NEMA sizes as indicated or required, with closed-circuit transition feature.
Construct controllers with two 3-pole contactors, 3-phase starting autotransformers, adjustable
pneumatic timer, fused 120V control transformer, push buttons, selector switches, indicating
lights, and 3-pole block type overload relay. Provide required and specified interlocks.
Construct autotransformer with voltage taps at 65% and 80% of full line voltage and with
thermal overload protection device on each phase to protect against overheating. Provide duty
cycle of 15-second operation out of each four minutes for one hour followed by rest period of
two hours. Provide integral main thermal magnetic circuit breaker or main motor circuit
protector. Manufacturer shall size and coordinate the main protective device with the
DEAN262900.DOC 262900-3