GE Consumer & Industrial
Electrical Distribution
Suit yourself
Get a power quality transformer that fits
imagination at work
Guard I. Guard II. Guard III.
Made to fit
Poor power quality in commercial and industrial facilities
is an ever-increasing problem. Power quality transformers
help, but one type is not right for everyone. GE’s unique
range of power quality transformers allow you to choose
the right solution at the right price for each application.
Noise isolation transformers
To help choose the right power quality transformer, it’s important to understand that there are two kinds of electrical noise:
common mode and transverse mode.
Common mode noise refers to the noise or voltage surges that occur between the neutral and ground conductors. It enters
the electrical system from overloaded power circuits, wiring faults and other equipment on the same line. Common sources
include lightning, ignition systems, poor grounds, radio transmitters, poor brush contacts on motors, and any arc.
Transverse mode noise refers to the noise or voltage surges that occur between the hot and neutral conductors. This type
of noise is caused by the firing of SCRs, welders, igniters, switching power supplies, electrical storms and utility switching.
Guard I
Guard II
Guard I noise isolation transformers provide common mode
noise attenuation and transverse mode noise attenuation.
Guard II noise isolation transformers provide common mode
noise attenuation plus an enhanced level of transverse
mode noise attenuation for increased protection of sensitive
electronic equipment.
Features
• Grounded copper electrostatic shield between primary
and secondary winding
• 120dB common mode noise rejection
• 30dB transverse mode noise rejection
• Single and three-phase ratings
• Compliance with ANSI and NEMA standards
• New lower TP-1 sound levels below ANSI limits
• 220°C insulation system
• UL & cUL listed
• NEMA 2 enclosure
Applications
• Retail stores
• High lightning strike areas
• Small computer installations
Features
• Grounded copper electrostatic shield between primary and
secondary winding
• Noise suppressors and spike/surge suppressors
• 120dB common mode noise rejection
• 60dB transverse mode noise rejection
• Single and three-phase ratings
• Compliance with ANSI and NEMA standards
• New lower TP-1 sound levels below ANSI limits
• 220°C insulation system
• UL listed
• NEMA 2 enclosure
Applications
• Schools and colleges
• Large computer installations
• Small commercial offices
• Motor installations
• Process controllers
• Hospitals
• X-ray rooms
• Electrical laboratories
• High lightning strike areas
Harmonic mitigating transformers
Guard III
Power supplies that convert AC to DC current – for plant floor
equipment, computers, copiers, electronic ballasts, etc. –
generate harmonics that create an irregular current waveform.
These harmonics in turn create such power quality problems
as overheated transformers, motors and neutral wires; nuisance
breaker trips; and electronic equipment malfunction and failure.
Guard III harmonic mitigating transformers help eliminate
harmonic currents and minimize these types of problems. In
addition, by canceling harmonic currents, they reduce energy
losses so you save money.
Guard III harmonic mitigating transformers don’t just filter
out unwanted electrical noise, they actually reduce the
effects of harmonic currents.
Features
• K-factor load profile of 20, crest factor load profile of 5
• Meets or exceeds NEMA TP-1 and CSA C802.2 efficiencies
• Copper windings
• 220°C insulation system
• NEMA 3R enclosure (NEMA 2 not available)
• UL and CSA listed
Applications
• Schools and colleges
• Industrial facilities
• Large commercial offices
• Hospitals
• Government offices
• Casino and gaming operations
Your guards against poor power quality
Guard I, Guard II and Guard III transformers guard against the harmful effects of poor power quality. They save money
by protecting commercial and industrial equipment and facilities from electrical damage by lowering maintenance and
equipment replacement costs. They are TP-1 rated, so they save energy. And they filter or reduce the harmful effects of
distorted “dirty power,” so electrical systems work better and more efficiently.
GE gives you a choice in power quality transformers, so you can choose the one that best fits a particular situation and
application. Typical choices are shown below. Your GE Distributor or Account Manager can give you more specific
guidance on your selection.
Noise isolation transformers Harmonic mitigating transformers
Application
Retail
Lightning strike areas
Small computer installations
Large computer installations
Schools/colleges
Small commercial office
Guard I
Guard II
•
•
•
•
•
•
•
Large commercial office
•
•
•
Hospitals
X-ray rooms
Laboratories
Data centers
Internet service providers
Call centers
Broadcast studios
LEED green buildings
Machine shops/small industrial
Guard III
•
•
•
•
•
•
•
•
•
•
•
•
•
Large industrial
GE Consumer & Industrial
41 Woodford Avenue
Plainville, CT 06062
www.geelectrical.com
imagination at work
DEA-403 (04/07)