60 to 50 Hz · 50 to 60 Hz · 60 to 60 Hz
Isolation · 50/60 to 400 Hz
Solid State Design Considerations
Solid State Vs. Rotary Design
12KVA, 1 phase, or less, solid
state design is generally preferred. The advantages are:
Lower cost
Lower operating noise level (<57dBa @ 3ft.)
More compact design
Crystal oscillator controlled frequency regulation and adjustable
but very tight voltage regulation.
Single phase units in this size
range are, in contrast to larger 3phase units, relatively
simple (4 pc boards) and easy to service in the field given an English
speaking technician. Solid state design is not suitable for loads
that in large part consist of devices (SCRs, triacs, IGBTs, high
capacity dimmers, welders etc.) that feed distortion back into the
line unless steps can be, or have been taken to isolate and filter
that distortion. Rotary units can be designed to handle such loads
(and, in fact, are often used to isolate such loads from others
in the same plant) - be sure to specify the nature of the load when
discussing rotary or solid state units with our application engineers.
Three phase units (5KVA and up)
utilizing our solid state IGBT design should be considered as an
option in those applications where:
Any single electric motor in the load constitutes less than
25% of the full load.
A 50% or more cost difference is acceptable (vs. rotary
design) in order to achieve quieter operation which the three
alternatives for rotary are unable to achieve in the particular
conditions. Conversely, a rotary design unit is always much less
expensive (over 12KVA), and especially so if motors and starting
surges are involved (Click Here
for Rotary)
An English speaking electrical technician with the ability to
use an oscilloscope is available or the unit can easily be returned
to the factory (in other words, it is in the U.S. or nearby) for
any repairs needed (or, of course, if in the case of non-warrantee
repairs, you are willing to pay travel, expenses, parts and labor
for our personnel to visit the site).
SCRs, Triacs and similar devices that feed distortion back into
the supply line (our unit in this case) do not constitute more
than 20% of the load or have input filtering or isolation built-in.
For applications involving small motors and sub fractional motors,
the limited motor starting surge capacity of the solid state design
will usually be the determining factor with regard to the KVA size
needed. For comparison, our smallest rotary a 6KVA single phase
unit will start and run a 2.5hp, design code F motor" cycling
across the line" and with oversizing of the generator can be
designed to handle up to a 4hp motor. We offer rotary units up to
2000KVA for starting motors up to 1500hp.
The motor starting capability of our solid state units are as follows:
1KSS6050/5060 will start and run a 1/4hp motor
2KSS6050/5060 will start and run a 1/2hp motor
3KSS6050/5060 will start and run a 3/4hp motor but will sound
overload alarm when starting, no damage to unit and ceases in
less than a second once the starting surge is finished.
4KSS6050/5060 will start and run a 1hp motor
5KSS6050/5060 will start and run a 1.5hp motor
6KSS6050/5060 will start and run a 1.5hp motor (a 2hp.no load,
starts but beeps, then stops beeping and functions with no problems
or damage - just an overload beep)
8KSS6050/5060 will start and run a 2hp motor
10KSS6050/5060 will start and run a 3hp motor
12KSS6050/5060 will start and run a 3.25hp motor
The above assumes that the motor will be started first and that
any additional load will be applied after the motor is started and
up to speed. If motor starting is part of the load, it would be
best to call 1-800-421-4430 and discuss sizing with our application
engineers since the "guaranteed performance" clause of our warrantee
then applies. Under this clause, with no discussion of who is at
fault or who said what, if the unit does not perform exactly to
your satisfaction, we pay the freight back and offer you either
the cash back or a larger replacement unit (at the larger units
price and we pay the freight to get the new unit to you).
Other useful hints:
If your equipment pulls 10A. at 110V., 60hz, it will pull 5A. at
220V., 50hz. etc.
Try not to use the amperage of the circuit breaker or fuse on your
equipment to size the converter as these are normally at least 20%
oversize and often much more which will result in your buying and
paying for a larger converter than you actually need. It would be
best to measure the amperage when the device is at full load on
the service it was designed for and record the voltage and amperage
being used, then recalculate the amperage for the intended voltage
at the new frequency.
Our stock units are designed for indoor use only and are in NEMA1
floor mounted enclosures (4KVA and over on casters). We do, however,
offer weather resistant and other enclosures with additional (3-4wk)
lead time. See Accessories.
If input power interruption is a problem, we offer battery backup
in a separate plug-in enclosure. See Accessories.