Specification Number: 16270-2.2A 
Product Name: SUBSTATION TRANSFORMERS
SECTION 16270-2.2A
SUBSTATION TRANSFORMERS

Liquid-filled - three-phase, substation type transformers are used in a wide variety of commercial and industrial applications.  All units are manufactured in accordance with applicable ANSI C57.12.00 standards.  The fluid filled transformers are offered with one of three different fluids:
Mineral oil – Type 2 biodegradable oil for outdoors
R-Temp(r) by Cooper Industries
561_silicone fluid (dimethyl polysiloxane) by Dow Corning 

PART 1 PRODUCT

1.01 MANUFACTURERS
A. Square D Company [no equal] [or approved equal].
1.02 FLUID-FILLED SUBSTATION TRANSFORMERS
A. The transformer(s) shall be the substation type with side-wall mounted primary and secondary terminations.
B. The average temperature rise of the windings, measured by the resistance method, shall be [55°] [65°] C when the transformer is operated at rated kVA output in a 40° C ambient. The transformer(s) shall be capable of being operated at rated load in a 30° C average, 40° C maximum ambient, as defined by ANSI C57.12.00, without loss of service life expectancy.
C. Coolant and insulating fluid shall be [inhibited mineral oil] [high fire point hydrocarbon R-Temp fluid manufactured by Cooper Industries] [dimethyl polysiloxane 561-silicone transformer fluid by Dow Corning].
D. Terminations shall be side-wall mounted for: [close-coupling to high and low voltage switchgear sections] [close-coupling to high voltage switchgear on the primary side and terminating in an air-filled terminal chamber for cable connections to the low voltage side] [close-coupling to low voltage switchgear on the secondary side and termination in an air-filled terminal compartment on the primary side for cable entrance] [terminations within air-filled terminal chambers on both high voltage and low voltage side for cable entrance and exit].
E. Primary and secondary locators shall be as follows: [primary: ANSI Segment 2, i.e. to observer's left when facing the transformer front; secondary: ANSI Segment 4, i.e. to observer's right when facing the transformer front] [primary: ANSI Segment 4, i.e. to observer's left when facing the transformer front; secondary: ANSI Segment 2, i.e. to observer's left when facing the transformer front].
F. Bushing location and phase rotation shall be coordinated with primary and  secondary switchgear to provide correct alignment when switchgear and transformer are connected in the field.
G. The transformer(s) shall be rated [ kVA OA] [ / kVA OA/FFA] [ / kVA OA/FA]. Primary voltage [delta] [wye], secondary voltage [delta] [wye], [3-   wire] [4-wire], 60 Hz with two 2-1/2% full capacity above normal and two 2-1/2% full capacity below normal taps. Impedance shall be [ %] Manufacturer's standard impedance], ±7-1/2%. Basic impulse level of the primary winding shall be [ kV]. As specified in IEEE C57.12.00 for comparable kV class.
H. Sound level, as measured by the NEMA audible sound-level test procedure, shall be less than the values specified in the following table when the transformer(s) (is) (are) operated at normal voltage and frequency and no load. kVA 225 500 750 1000 1500 2000 2500 3000 3750 5000 dB 55 56 58 58 60 61 62 63 64 66
I. The transformers shall be of sealed-tank construction of sufficient strength to withstand a pressure of 7 psi without permanent distortion. The cover shall be welded. The transformer shall remain effectively sealed for a top oil temperature range of -5° C to 105° C. When required, cooling panels will be provided on the back and front of the tank. Lifting eyes and jacking pads will be provided.
J. Coils shall be wound with [copper] [aluminum] conductors.
K. Core and coil assembly shall be the [wound core type, providing 5-legged construction] [stacked core type, providing 3-legged construction]. Cores shall be fabricated of high grade, grain-oriented, silicon steel laminations, carefully annealed after fabrication to restore high magnetic permeability. Magnetic flux is to be kept well below the saturation point.
L. Tank, radiators, and terminal chambers, if provided, shall be treated to remove oil and scale by either shotblast or phosphatizing treatment to provide proper paint adhesion. All exterior surfaces shall be primed, using a high quality solid two-paint catalyzed epoxy. Minimum dry film thickness shall be 2 mils. A durably hard polyurethane top coat with a minimum dry film thickness of 1 mil shall be applied to all primed surfaces. The color of the finish coat shall be [ANSI 49] [ANSI 61] [ANSI 70] [ANSI 24] and shall be coordinated with the switchgear manufacturer in order to match the color of the switchgear.
M. Accessories - The following accessories shall be included on all substation transformers:
1. Padlockable tap changer for de-energized operation
2. Upper filling plug and filter press connection
3. Drain valve with a 3/8 inch sampler
4. Dial type thermometer
5. Pressure/vacuum gauge [with] [without] bleeder connection
6. Magnetic liquid level gauge
N. Pressure relief valve, with manual bleeder and automatic resealing, set to operate at 10 psi with a flow rate of [35 scfm] [50 scfm]:
1. Alarm contacts on [all gauges] [dial thermometer] [liquid level gauge] [pressure vacuum gauge]
2. Pressure relief diaphragm to operate at 10 psi and relieve 10,000 scfm at 15 psi
3. Sudden pressure relay permitting remote alarm or trip due to a predetermined rate of pressure rise [with] [without] seal-in delay
O. The transformer(s) shall be designed for use with fans to increase the current carrying capability in accordance with the ratings of Article 2.02 paragraph G preceding. The transformer shall be equipped with forced air cooling or be designed for the future addition of forced air cooling. The fan control equipment will be actuated by contacts that sense [the temperature of the top oil] [the average winding temperature] of the     transformer. Temperature sensors, motor starter for fan motors, test modes of operation, as well as fans and fan motors, will be provided on units designated OA/FA. Temperature sensors and details for future mounting of fans and controls will be provided on units designated OA/FFA. Fan motors will operate from a 240 V, single-phase, 60 Hz source of power provided by the user.
P. Testing - Tests shall be conducted in accordance with the provisions of IEEE C57.12.90 and shall include, as a minimum, the following tests:
1. Ratio
2. Polarity
3. Phase Rotation
4. No-Load Loss
5. Excitation Current
6. Impedance Voltage
7. Load Loss
8. Applied Potential
9. Induced Potential
10. Impulse Test
11. Temperature Test (typical data from previous unit is acceptable)
12. Sound Test (typical data from previous unit is acceptable)

													
END OF SECTION
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