Reduced Voltage
Autotransformer Starters
Reduced voltage starters shall be
Siemens Type SAT for motors up to 900
HP, 600V. Starter shall be the closed tran-
sition type providing field adjustable volt-
age taps for 50, 65, and 80% of the line
voltage. The autotransformer shall be a
NEMA medium duty with internal thermal
protectors for protection of overheating
due to excessive repeat starts that
exceed the allowable number of starts on
the transformer. Incomplete sequence
protection is to be provided on all NEMA
size 6–8 starters.
Autotransformer starters shall be
equipped with three-pole double-break
contactors with an arc quenching system
consisting of arc chutes with arc splitter
plates and a maximum 2 millisecond
bounce time on sizes 2–5 to extend con-
tact life. Run contactor shall be capable of
carrying a minimum of 840% full-load cur-
rent for 10 seconds duration on sizes 2–5.
Starter shall include two three-pole con-
tactors, to connect the autotransformer
for reduced voltage starting, and a two-
pole (run) contactor to bypass the auto-
transformer and connect the motor for
full voltage across-the-line running after
a predetermined starting time is reached.
A transition timer shall be provided which
can be field adjusted to set the starting
time. Starters shall be equipped with
three-pole overload relays. Overload relay
shall be a block type NEMA Class 10 with
push to test feature, phase unbalance and
phase loss protection, be field adjustable,
and have an isolated alarm circuit contact.
For NEMA Size 6–8 starters, the overload
relay shall be a 3UB solid state micro-
processor controlled device and have a
field adjustable class setting from Class
10 through Class 30 to compensate for
long accelerating times.
The starters shall be built and tested in
accordance with the latest NEMA
standard ICS 2-321 and UL Listed.
Multi-Speed Starters
Type S1, S2 multi-speed starters shall be
equipped with three-pole, double-break
contactors with an arc quenching system
consisting of arc chutes with arc splitter
plates, and a maximum 2-millisecond
bounce time on sizes 2–5 to extend
contact life.
Starters shall be equipped with three-pole
overload relays. Overload relay shall be a
block type NEMA Class 10 with push-to-
test feature, phase unbalance and phase
loss protection, be field adjustable, and
have an isolated alarm circuit contact. For
NEMA Size 6–8 starters, the overload
relay shall be a 3UB solid state micro-
processor-controlled device and have a
field adjustable class setting from Class
10 through Class 30 to compensate for
long accelerating times. The starters shall
be built and tested in accordance with the
latest NEMA standard ICS 2-321 and UL
Listed.
Reduced Voltage Wye
Delta Starters
Wye Delta Open And Closed
Transition Starters
Wye delta starters shall be equipped with
three-pole double-break contactors with
an arc quenching system consisting of arc
chutes with arc splitter plates and a maxi-
mum 2-millisecond bounce time on sizes
2–5 to extend contact life. Starter shall
include three 3-pole contactors sized per
NEMA standard ICS-2-321-7 and appropri-
ate mechanical interlock.
A transition timer shall be provided which
can be field adjusted to set the starting
time. A fourth contactor will be used on
closed transition starters with transition
resistors wired in each phase. An incom-
plete sequence relay shall be included to
protect the transition resistors in the
event the transition is not completed.
Wye delta starters shall be equipped with
a three-pole overload relay wired in the
phase windings.
Overload relay shall be a block type
NEMA Class 10 with push to test feature,
phase unbalance and phase loss protec-
tion, be field adjustable, and have an iso-
lated alarm circuit contact. For NEMA size
6–8 starters, the overload relay shall be a
3UB solid state microprocessor controlled
device and have a field adjustable class
setting from Class 10 through Class 30 to
compensate for long accelerating times.
The starters shall be built and tested in
accordance with the latest NEMA
Standard ICS 2-321 and UL Listed.
Reduced Voltage, Part
Winding Starters
Part Winding Starters
Part winding starters shall be equipped
with three pole double break contactors
with an arc quenching system consisting
of arc chutes with arc splitter plates and a
maximum 2-millisecond bounce time on
sizes 2–5 to extend contact life. Starter
shall include two three-pole contactors
mechanically interlocked. A transition timer
shall be provided which can be field adjust-
ed to set the starting time. Starters shall
be equipped with three-pole overload
relays. Overload relays shall be a block
type NEMA Class 10 with push-to-test
feature, phase unbalance and phase loss
protection, be field adjustable, and have an
isolated alarm circuit contact. For NEMA
size 6–8 starters, the overload relay shall
be a 3UB solid state microprocessor con-
trolled device and have a field adjustable
class setting from Class 10 through Class
30 to compensate for long accelerating
times. The starters shall be built and test-
ed in accordance with the latest NEMA
Standard ICS 2-321 and UL Listed.
Solid State Reduced Voltage Starters
Voltage Limit:
To set a soft start, no
need to know full load amps regardless
of motor size (it limits inrush current dur-
ing the starting period). It reduces peak
torques at near synchronous speed com-
pared to current limit start.
Impulse Start:
Provides breakaway
torque for high friction loads such as
crushers or mixers, it reduces motor
heating compared to ramp starts.
Shunt Trip:
For positive isolation on fault
conditions; in case of 2 shorted SCR’S.
Emergency Start:
With a shorted SCR,
controller should be able to soft start and
run to save the process.
Under / Over Voltage:
Under over volt-
age protection prevents motor and con-
troller damage.
UL Ratings:
UL Listed and short circuit
tested for 65 kA or higher with circuit
breakers (magnetic trip only breakers).
Short circuit tested for 100 kA with RK5
fuses.
Diagnostics:
On board fault diagnostics
with selectable fault relay output.
Initialization Check:
50-millisecond
check on start; for short circuit, power
line conditions, and load connections.
Re-Start of Rotating Motors (Start on
the Fly):
Starting motors with applied
BEMF (back electro magnetic force) with
no transients. No need to wait for field
to collapse or decay. Smooth reversing.
Power Outage:
Ride-through power out-
ages for 0.5 seconds on control power
up to 5 seconds on primary power.
SCR Thermal Protection:
Temperature
and current predicting model to protect
SCR’s for all conditions by keeping semi-
conductors below the rated junction
temperature.
Fully Isolated Electronics:
All inputs,
relays and DC power components must
be isolated from customer connections
to provide noise immunity, 2500 volt di-
electric with start.
Inputs:
All inputs must operate on 120
volts including remote reset input.
Communications:
Communications port
must be provided on the electronics to
interface with IBM compatible PC via
RS232 link.
Specifications
312
CSI Section 16160
Siemens Electrical Products and Systems
Specification Guide
AC Controls
15
AC Controls
Guide Form Specifications
