Larson Electronics, LLC
Phone: 877-348-9680
Fax: (903) 498-3364
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of
10
STATIC PHASE CONVERTER
INSTRUCTION SHEET
CAUTION:
Read the following carefully before
attempting installation.
Using the converter as in Method No. 1 will produce
approximately 2/3 rated horsepower.
Heavily loaded applications
, such as compressors,
blowers, water pumps, hydraulic pumps, etc., a 50%
larger motor must be fitted. Otherwise, Method No. 2,
shown on reverse side of this page, could be used. Or, use our
full power Rotary Phase Converter.
SELECTION:
The horsepower range
of the static converter is determined by
the minimum and maximum starting current applied to it at any
one time. The largest motor on your machine, or the idler
motor, if used, must fall within the minimum and maximum
horsepower range marked on the static converter. Do not
add the horsepower of the power feed, coolant pump, etc.
These rely on the generator effect of the main motor. The
only time you would add the horsepower of two or more
motors together would be if they always start at exactly the
same time. Do not install a larger size or Heavy Duty
series static converter thinking it will give you more
horsepower.
A static converter that is too large will not work
properly and may cause damage.
Two-speed motors
are dual horsepower. Select the static
phase converter with minimum and maximum horsepower
ratings, which fall within or very close to the minimum and
maximum horsepower of the motor. For example: A 1.5 HP
3450 RPM motor is ¾ HP at 1725 RPM.
Some European
soft-start motors draw less starting current
than normal and therefore require a smaller than normal
converter. Most Taiwanese and Chinese motors draw greater
amperage to start than normal. Therefore, for these motors we
recommend a 3 HP motor; a 5 HP motor; a 7.5 HP motor, etc.
WHEN TO USE HEAVY DUTY SERIES
Lathes above 3 HP
not fitted with a clutch.
Air compressors
, the motor pulley diameter must be
reduced by 1/3, or a 50% larger motor must be fitted.
Long, heavy starting
cycles, frequent starting or instant
reversing, unattended motors, if jogging is required, or if
there is a chance of the motor being stalled during use.
Larson Electronics, LLC.
9419 US-HWY 175
800-369-6671 • FAX 903-498-3364
E-mail: [email protected]
2019 FORM
Static Phase Converter used to start the load motor
1.
220V single-phase
lines L1 and L2 are connected to the A and
B terminals of the converter.
2.
Do not connect
220V power, or a ground or neutral wire from the
utility, to the C terminal of the converter, as the resulting dead
short would damage it instantly. The single-phase neutral wire is
not required for operation of the converter.
3.
Properly ground
all electrical equipment for safety. Use a
grounding clip to attach the ground wire to the conduit box.
4.
Fuses
should not be used on the three-phase lines between the
static phase converter and the motor. A blown fuse still leaves
two lines to conduct, which can damage the converter. Magnetic
starters are preferred. Fuses can be used on the single-phase
lines L1 and L2 from the utility power to the converter. Single-
phase wires and fuses should be sized as appropriate for the
rated amperage of the motor. See chart below.
5.
Size the breaker
on the single-phase approximately twice the
amperage rating of the motor at the 220V configuration. See chart
below.
6.
For machines with magnetic switchgear, resistive or single-
phase load:
Resistive or single-phase loads and/or magnetic
switchgear must be connected only to lines A and C from the
converter. DO NOT connect the static phase converter until you
identify which two wires operate the magnetics. To easily locate
these two wires, connect 220V single-phase power to any 2 of
the 3 wires on the machine and press the start button. When the
correct combination is found the magnetics will work. Connect
these two wires to the outside terminals of the converter,
terminals A and C, and the third wire to the center terminal, B.
The magnetics should still work with the center terminal (line B)
disconnected. Your motor’s magnetic overload protection remains
the same; no changes are necessary.
7.
For indoor use
only. Do not use in wet or damp locations.
8.
Do not mount
on equipment with excessive vibrations.
9.
Refer to NEC Code
#455 for details on field installation issues.
Breaker & Wire Size - Refer to NEC Code #430 C
HP
1
2
3
5
7.5
10
15
20
25
30
40
50
Breaker
Amps
15
15
20
30
40
60
100
125
160
200
250
300
Wire Size
Gauge
14
14
12
10
8
6
3
1
1/O
3/O
4/O
300
mcm
Fuses*
10
10
15
30
40
45
60
80
100
125
150
200
Conduit
Size In.
1/2
1/2
1/2
1/2
1/2
1/2
3/4
1
1
1
-1/4
1
-1/4
1
-1/2
*Fuses
, if used, are
time delay, dual element
for 1-phase lines
L-1 and L-2 only; do not use on 3-phase lines to the motor.
Kemp, Tx. 75143
