TwinSource Power Systems, Inc.
STS Configurator Request quote
Single and three phase · 10 to 600 A

Static transfer switches,
from the rack to the electrical room

TwinSource static transfer switches give critical equipment a second, independent source and switch to it as fast as a quarter cycle per phase, protecting single-source loads and adding redundancy to dual- and multi-source systems.

Configure a switchRequest a quote
DCC-4-W wall mount static transfer switch under the busway, above the TPU/GPU racks
DCC-4-W under the busway, above the TPU/GPU racks 10–100 A
70M+ hoursof reliable online performance without load interruption
¼ cycletransfers as fast as ¼ cycle per phase
10–600 Asingle and three phase, rack, wall and free standing
Made in the USAwith U.S. and imported parts

See a transfer

Two independent sources come in. One protected output goes out. When the preferred source leaves its window, SCRs move the load to the other one before the equipment can notice. Fail the source and watch.

What is a static transfer switch?Transfer time basics

Find your switch

Start with where the load is. The configurator narrows the range as you add voltage, current and poles, in any order.

Rack mountIn the rack with the equipment. 10 to 200 A.Wall mountWhere wall mounting gets you close to the load. 10 to 200 A.Free standingPanels and large loads. 100 to 600 A.

Products

Rack Mount STS

10–200 A, static switches, single and three phase

Wall Mount STS

10–120 A, three phase, 3-pole or 4-pole

Free Standing STS

100–600 A, eight ratings

Single Phase STS

10–600 A, static, up to 144 kVA per switch

Three Phase STS

10–600 A, sixteen standard ratings

ATS

12, 16, 24 A, single phase, 100–240 V

All products

Where they work

BUSWAY ABUSWAY BBUSWAY CTPU RACKSTWO STS-FED INPUTS PER RACKCDUWALL-MOUNT STS

AI Data Centers

SECONDARY LOOPFACILITY WATERABLIQUID-COOLED RACKSCDUSTS

Cooling Distribution Units (CDUs)

CRITICAL ACRITICAL BTOWERRADAR DISPLAYCONTROLLER POSITIONSTS

Air Traffic Control Applications

FEEDER AFEEDER BPROCESS TOOLPROCESS TOOLSTSSUBFAB

Semiconductor / Chip Fabrication

STATION SERVICE 1STATION SERVICE 2TRANSFORMERSCADA + STSRTUOPERATOR HMI

SCADA / Utility Controls

ABSINGLE-CORDED LOADS + STSCRAH

Traditional Data Centers

All 12 applications

Why TwinSource

U.S.-based support and serviceYou are not just buying a box: you are getting a partner for the life of your equipment. TwinSource stands behind its products and supports its customers from specification to start-up through equipment performance life.
25+ years in mission-critical powerSince 2001, TwinSource has built robust, reliable transfer switches for the most mission-critical loads.
Built for the bad dayExtremely fast break-before-make transfers at any phase angle, because a failing source needs to be removed.
Serviceable under loadBypass isolation or maintenance bypass on every static model. An alarm never has to end in a shutdown.

Learn from the people who build them

What Is a Static Transfer Switch?A static transfer switch moves a critical load between two independent AC sources in milliseconds, using SCRs, not contacts. How it works, what to check.STS vs ATSStatic transfer switches use SCRs; automatic transfer switches use moving parts. Compare transfer time, out-of-phase transfers, bypass and uses.How to Size a Static Transfer SwitchConvert kW or kVA to amps, add margin and choose a 100% rated static transfer switch. Includes a sizing calculator.Where to StartSeven decisions before buying a rack-mount transfer switch: rating, power factor, criticality, fleet MTBF, bypass, verification and fault protection.

All resources

Tell us about the load

Build a quote request from the configurator, or call (440) 248-6800 and talk to an engineer.

Request a quoteContact us