TRIP CURVE
TYPE C306 BIMETALLIC COMPENSATED
OVERLOAD RELAY 25°C OPEN RATING
TRIP CURVE
TYPE C306 BIMETALLIC COMPENSATED
OVERLOAD RELAY 25°C OPEN RATING
CLASS 10
TYPE C306
OVERLOAD
RELAY
CLASS 20
TYPE C306
OVERLOAD
RELAY
SIZE 1
REVERSING
STARTER
SIZE 0
REVERSING
STARTER
GENERAL
Magnet Coil — Magnet coils are encapsulated dual volt-
age/frequency coils which are color coded and permanently
marked with voltage, frequency and part number. Coil terminals
are located on top for easy accessibility.
Overload and Heater Packs —
Overload relays used on
“Freedom Series” starters come in four sizes — 32 amperes,
75 amperes, 105 amperes and 144 amperes. They can be
attached directly to contactors (panel mount or common
mounting plate) or, with a panel mounting adapter, as a stand
alone panel mounted 32 ampere or 75 ampere overload
relay. The panel mounting adapter also provides a terminal
block for line side wiring to the stand alone overload relay.
Sizes 5-9 use 32 amps with CT’s.
The overload relay houses an adjustable, trip-free mechanism
and provides mounting for three heater packs. The mechanism
is bimetallic with ambient compensated operation. Single
phase protection is built in. The reset mechanism can be set for
AUTO or MANUAL operation. lt has
± 24% adjustability to
match motor full load ampere rating with calibration for 1.0 or
1.15 service factor motors. Two isolated contacts, one NC and
one NO can be tested by pulling the RESET button. The NC and
NO contacts are rated B600 and C600 (refer to Ratings tables
on Page 8) respectively. Like the contactor, the overload relay
has “finger proof” terminals to reduce the possibility of electrical
shock.
Tamper proof overload relay adjustment locking covers snap
over the top of overload relays to prevent accidental turning of
trip or reset adjustments. Consult the Industrial Control Catalog
for information on the variety of covers available.
Visual trip indication is provided on all overload relays. The
indicator window is located on the lower right-hand corner of the
switch unit, just below the reset button. Upon an overload trip
(or by pulling up on the reset button), a fluorescent orange
indicating flag will appear in the window. Trip indication is only
present when using Manual Reset.
The heater packs are securely held in the overload relay by two
captive screws. Three Class 20 (Class 10 optional) heater
packs are installed in the overload relay. The 32 ampere heater
packs will mount in the 75 ampere overload relay for applica-
tions where the contactor is derated such as for jogging.
The overload relay is adjustable within the FLA range of the
heater pack and will ultimately trip at 125% motor current. After
the heater packs are selected and installed in the overload
relay, the FLA adjustment dial should be rotated to the dial
position corresponding to the motor FLA.
The “Freedom Series” starters feature a compact space saving
design using state-of-the-art technology and the latest in high
strength, impact and temperature resistant insulating materials.
Reversing Starters
Three phase, full voltage magnetic starters are used primarily
for reversing of polyphase squirrel cage motors. They consist
of two contactors and a single overload relay assembled to-
gether. The contactors are mechanically and electrically inter-
locked to prevent line shorts and energization of both
contactors simultaneously.
NEMA, Contactors & Starters, (Freedom)
Technical Information Publication
8231
Page 3
February 2, 1998
To Next Page
Loading...
Need help?
General