DELAYED TRANSITION TRANSFER SWITCHES
The CTSD provides an adjustable time delay after
the opening of the closed contacts and before the
closing of the open contacts for transferring large
motor and/or transformer loads. This delayed
transition time allows for motors to coast down
and transformer fields to decay, thus allowing
inductive loads to be re-energized after transfer
with only normal inrush starting currents.
The delayed transition design is an effective
method of handling these applications and can
be utilized as an alternative to a standard transfer
switch equipped with an in-phase monitor.
The delayed transition transfer switch is ideally
suited for pumping stations, sewage treatment
plants, hospital X-ray equipment, or wherever
the bulk of the load being controlled consists of
large motors and/or transformers. Further, many
UPS manufacturers strongly recommend the use
of delayed transition type transfer switches to
ensure proper operation and sequencing of
their equipment.
The CTSD Series allows a typical UPS system
sufficient delay to recognize a power failure and
transfer to batteries, acknowledge the return of
input power and allow the rectifier to walk-on to
the new source, reducing any transfer anomalies.
Except for the adjustable delayed transition
period, the performance, operating capabilities,
ratings, UL listings, withstand current values and
available options are identical to those of the
CTS Series Automatic Transfer Switches.
The CTSD incorporates all of the important
features of the standard CTS Series switch.
In addition, its unique design incorporates
features oriented toward its specific operation
