GE Industrial Solutions Fan Assisted Cooling User Manual

Installation Guide 475A667AAP008 Rev 004

Fan Assisted Cooling (FAC) Dry-Type Transformers

Three Phase, 150-1000 kVA

Instructions for the Safe Handling, Installation, Operation and Maintenance.

Table of Contents Page Table of Contents (Cont.) Page

6.2

1.

General Information………………………...

2.

Temperature Class………………………….

3.

Handling……………………………………...

4.

Receiving…………………………………….

5.

Installation……………………………………

5.1

Preparation…………………………...

5.2

Mounting and Placement…………...

5.3

Ventilation…………………………….

5.4

Audible Sound Sources……………..

6. Connections………………………………….

6.1 Cable Conduit Entrance / Lugs…….

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2
2
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3
3
3
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4
4

Grounding…………………………….

6.3

Lighting Tap Applications……..…….

6.4

Fans, Alarm and Shunt……………...

7.

Before Energizing…………………………...

8.

Operation…………………………………….

8.1

Loading……………………………….

8.2

Over-excitation……………………….

9.

Troubleshooting……………………………..

10.

Maintenance…………………………………

11.

Storage……………………………………….

12.

Renewal Parts……………………………….

13.

Typical Enclosure Information……………..

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1.

+ Hot Spot

General Information

Fan assisted cooling (FAC) dry type transformers have a ventilated, encased construction suitable for indoor service only unless
converted for protective outdoor service. All models are designed for floor or platform mounting. The core and coil structure is
mounted directly to the enclosure allowing all-around and floor access for cabling. Rubber isolation pads are included as a kit and
can be mounted at the base to minimize transmission of vibration. An optional bottom panel has to be in place for wall-mounted
transformers; however, the bottom panel installation is optional for transformers mounted on flat non-combustible surfaces.

Rain-shield conversion kits are available to convert standard indoor NEMA Type 2 enclosures to NEMA Type 3R enclosures
suitable for protected outdoor installation. The transformer nameplate specifies the proper kit to match the indoor enclosure and
transformer. The enclosure has vent guards that deter rodents, birds or debris from entering.

Each transformer is assembled and given complete electrical tests at the factory, after which it is inspected and packed for shipment.

2. Temperature Class

Industry standard UL 1561 classifies insulation systems in accordance with the following rating system:

Ambient + Winding Rise

40C 55C 10C 105C
40C 80C 30C 150C
40C 115C 30C 185C
40C 150C 30C 220C

Transformers for applications requiring lower temperature rise, generally 115C and 80C, are readily available.

Transformers operating at full load will have a maximum 50C/122F temperature rise on the surface areas of the enclosure. With a
40C ambient, the measured enclosure surface temperature could be as high as 90C/194F.

= Temp Class

All FAC dry-type transformers meet applicable IEEE, ANSI,
NEMA and UL standards.

These transformers are designed using a 220C insulation
system with a standard 150C temperature rise.

3. Handling

Provisions for lifting are provided. Because transformers are surprisingly heavy, check the weight shown on the nameplate or the
shipping label to assure adequate capacity of lifting equipment. For safety, spreaders should be used with lifting equipment.

CAUTION

THE ENCLOSURE IS AN INTEGRAL PART OF THE STRUCTURE SUPPORTING THE TRANSFORMER. NEVER LIFT
THE UNIT WITHOUT THE ENCLOSURE IN PLACE (OTHER THAN THE COVER WHICH HAS TO BE REMOVED TO
ACCESS LIFTING HOLES ON TOP CORE CLAMPS). ALWAYS MOVE TRANSFORMER IN AN UPRIGHT POSITION.

To move unit with a pallet jack or fork truck, remove the four bolts on front and rear lifting grills, reattach the lifting grill in the
raised position (using bottom holes in the grill) and lift on both grills (exercise caution to prevent damage to fan cables). When
transporting is complete, return lifting grills to the lowered position. Refer to enclosure assembly picture on last page.

4. Receiving

Upon receipt of shipment, examine the package for damage that may have been sustained in transit. If the unit must be opened
outdoors, take proper precautions to prevent the entrance of moisture. While unpacking, examine the product for broken, bent,
loose parts or other damage. If damage from shipment is evident, file a damage claim with the transportation company and notify
the nearest sales office.

5. Installation

Dry-type transformers should be located in an area where the transformer can be inspected at any time. It is a requirement of NEC
that sufficient access and working space be provided and maintained about all electrical equipment to permit maintenance.
Maintenance on FAC units can be done from the front, so working space clearance need only be provided to the front.

TO AVOID ELECTRICAL SHOCK DO NOT REMOVE COVERS WHILE TRANSFORMER IS ENERGIZED.

TRANSFORMERS OPERATE AT HAZARDOUS VOLTAGES THAT COULD CAUSE SEVERE INJURY OR DEATH!

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WARNING

CAUTION

ONLY EXPERIENCED AND QUALIFIED PERSONNEL SHOULD PERFORM INSTALLATION AND MAINTENANCE. NO
ATTEMPT SHOULD EVER BE MADE TO CHANGE THE TAPS OR MAKE CABLE CONNECTIONS WHILE THE
TRANSFORMER IS ENERGIZED.

TRANSFORMERS SHOULD BE INSTALLED IN SECURE, CONTROLLED ACCESS AREAS, NEVER IN AREAS SUBJECT
TO DELIBERATE, UNAUTHORIZED ACTS BY MEMBERS OF THE UNSUPERVISED PUBLIC. IF INSTALLED IN SUCH
AREAS, TAMPER RESISTANT ENCLOSURE SCREWS SHOULD BE USED.

5.1 Preparation

Remove any accumulation of dirt or dust by vacuuming, brushing or blowing dry air on the unit. If moisture is evident by the
appearance of rust or mildew or moisture is visible on the insulation surfaces or on the fans, the unit should be dried out by placing
it in an oven or by blowing heated air over it. In either case the temperature should not exceed 110C/230F. Insulation resistance
tests of the type used on liquid filled transformers are of little value on dry-type transformers. The nature of insulation used in dry
type transformers is such that megger readings are not reliable and may be misleading. Refer to ANSI/NEMA C57.12.91 paragraph

10.9 for additional information.

5.2 Mounting and Placement

The only foundation necessary is a non-combustible flat surface strong enough to support the weight of the unit. Note that
permanent and effective grounding of the metal case in accordance with NEC is recommended as a safety precaution.

Free circulation of ambient air is essential for the proper operation of all FAC dry-type transformers. The sides of the transformer
with ventilation openings require a minimum distance of six inches to adjacent noncombustible structures or equipment to ensure
proper circulation of air. Refer to enclosure assembly picture on last page.

CAUTION

TRANSFORMERS SHOULD BE INSTALLED AT LEAST TWELVE INCHES FROM COMBUSTIBLE MATERIALS,
INCLUDING MOUNTING SURFACE UNLESS SEPARATED BY FIRE RESISTANT HEAT INSULATING BARRIERS.
SPECIFIC REQUIREMENTS ARE DESCRIBED IN NEC, SECTION 450-21. CHECK LOCAL CODES.

5.3 Ventilation

FAC dry-type transformers are cooled both by free circulation of surrounding air and by forced circulation of air. They depend on
air to enter at the bottom, flow upward over the core and coil surfaces and exit through the openings near the top. These
transformers will carry full-rated loads continuously when the surrounding air does not exceed 30C/86F average, 40C/104F
maximum and adjacent structures permit free movement of cooling air.

The room in which dry-type transformers are located should be sized to permit locating transformers with sufficient spacing
between units and sufficient clearances to walls and other obstructions to permit the free circulation of air around each unit and to
minimize noise amplification. Sufficient space should also be maintained to permit routine inspection and maintenance.

Adequate ventilation is essential for the proper cooling of transformers. Clean dry air is desirable. Filtered air at or above
atmospheric pressure may reduce maintenance if dust or other contaminants present a problem. When transformers are located in
rooms or other restricted spaces, sufficient ventilation should be provided to hold the air temperature within established limits
(30C/86F average over 24 hours with a 40C/104F maximum) when measured near the transformer inlets.

5.4 Audible Sound Sources

The audible sound produced by FAC transformers is partially due to the energizing of the core by the alternating voltage applied to
the windings and also by the fans forcing air through the coils. The noise generated by the core creates vibrations whose
fundamental frequency is twice the frequency of the applied voltage. The audible sound will be present even under no load
conditions. The vibrations producing audible sound can occur in the core, coil, mounting, housing, and in the conduit. The
transmission of sound from the transformer can be by various media such as air, metal, concrete, wood or any combination.

Amplification of audible sound can occur in a given area due to the presence of reflecting surfaces.

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