T-85.01.pdf

Page: T - 85.01

Gainesville Regional Utilities Electric System Approved Materials Manual

TRANSFORMER, SINGLE PHASE (PAD)

(TECHNICAL SPECIFICATIONS)

Revision Date:

9-22-15 KLC

5-4-18 KLC

4-5-19 KLC

6-4-19 KLC

7-29-19 KLC

M o r e t h a n E n e r g y

SM

ITEM NAME

TECHNICAL SPECIFICATIONS

LOW PROFILE SINGLE PHASE PAD MOUNTED TRANSFORMERS

4. DESIGN AND CONSTRUCTION

4.1 General

(1) Pad-mounted compartmental-type transformers shall consist of the transformer tank and a high and low voltage terminating compartment. The transformer tank and terminating compartment shall be assembled as an integral unit, tamper resistant and weatherproof for mounting on a pad.

(2) The transformer shall be 100% Stainless Steel (S.S. 304) construction.

(3) The transformer hood shall have a raised locking assembly located high on the transformer hood. (See drawing on page T-85.02).

(4) The transformer shall conform to ANSI C57.12.25- 1990 and ANSI C57.12.28-2005, except as otherwise modified herein.

(5) All units shall have interlaced secondary design or an approved secondary surge protective device.

Manufacturers shall submit surge protective device schemes for approval by the GRU Energy Delivery Standards prior to quotation.

(6) Transformers shall not deviate from the allowable dimensionnal limitations shown in figure 3, of this specification.

(7) Transformer cores shall be constructed of high grade, cold reduced, grain oriented silicon steel with low hysteresis and eddy current losses.

Transformer cores shall not be constructed of amorphous metal.

4.2 Bushings and Terminals

(1) The terminal arrangement shall be as specified in the ANSI C57.12.25-1990 for Type 2 terminal arrangements with minimum dimensions as specified in Figure 2 of ANSI C57.12.25-1990, for a rating of

8.3 kV, except that the distance between the H1B (high voltage) bushing and the X3 (low voltage) bushing shall be a minimum of 10.0 inches when measured horizontally from the center of each bushing.

(2) The transformer shall be supplied with 8.3/14.4 kV class bushing wells and loadbreak bushing inserts for transformer sizes 25, and 37.5, kVA which conform to the requirements of ANSI/IEEE standard 386-1985. The sizes 50, 75, 100 and 167 kVA transformer shall be supplied with an Elastimold

1. SCOPE

1.1 This specification covers the electrical and mechanical

requirements for single phase, sixty cycle, oil filled, self cooled, pad mounted, distribution transformers, in various kVA ratings for use on an underground electric distribution system.

2. APPLICABLE DOCUMENTS

2.1 Unless otherwise indicated all transformers shall conform to the latest issue of the following American National Standards Institute (ANSI) documents:

(1) IEEE C57.12.00-2006 or latest revision, General Requirements for Liquid-Immersed Distribution, Power, and Regulating Transformers.

(2) ANSI C57.12.25-1990 or latest revision, Requirements for Pad mounted, Compartmental Type, Self Cooled, Single Phase Distribution Transformers with Separable Insulated High-Voltage Connectors; High Voltage, 34,500 grd. Y/19,920 Volts and Below; Low Voltage, 240/120 volts; 167 kVA and Smaller.

(3) ANSI C57.12.28-2005 or latest revision, Switchgear and Transformers Pad Mounted Equipment Enclosure Integrity.

(4) Department of Energy (DOE), 10 CFR Part 431, Energy Conservation Program for Commercial Equipment: Distribution Transformers Energy Conservation Standards, Final Rule RIN 1904-AB08, [Docket Number: EE-RM/STD-00-550]

3. RATINGS

3.1 All ratings shall be based on not exceeding a 65 degree C.

winding temperature rise. The high voltage basic impulse insulation level (B.I.L) shall be 95 kV.

3.2 Transformers that currently exceed the January 1, 2016, DOE minimum efficiency levels shall remain at these efficiency levels. All other transformers shall meet or exceed the January 1, 2016, DOE minimum efficiency levels, effective 4/30/08.

3.3 High voltage: 12470 Grd.Y/7200

3.4 Low voltage: 240/120

3.5 Size (kVA): 25, 37.5, 50, 75, 100, 167, as indicated on the request for quotation.

Page: T - 85.02

Gainesville Regional Utilities Electric System Approved Materials Manual

TRANSFORMER, SINGLE PHASE (PAD)

(TECHNICAL SPECIFICATIONS)

Revision Date:

9-22-15 KLC

5-4-18 KLC

4-5-19 KLC

6-4-19 KLC

7-29-19 KLC

M o r e t h a n E n e r g y

SM

ITEM NAME

5/16" hole location Figure 1.

4.5 Dielectric Oil

(1) Transformers shall be furnished complete with oil which does not contain more than 1 ppm PCB’s (see subparagraph (4) below) and shall be labeled as not contaminated.

(2) The transformer shall be of a sealed-tank construction.

(3) The transformer shall remain effectively sealed for a top oil temperature range of 5 degrees C to +105 degrees C.

(4) The manufacturer shall certify that the liquid dielectric or any component of the liquid dielectric is not listed in the Federal Register, Vol. 45, No. 98, issued Monday, May 19, 1980, 40FR Part 761, Appendix VIII Subpart D - Identification and Listing of Hazardous Waste.

4.6 Tank

(1) The tank construction shall comply with ANSI C57.12.25-1990.

(2) The tank shall be of all-welded Stainlees Steel (SS304) construction. There shall be no exposed screws, bolts, or other fastening devices which are externally removable. The top shall be pitched to facilitate water run-off.

extended loadbreak bushing insert, catalog number 1601EA4, or equivalent. Bushing wells shall be externally clamped.

(3) The transformers shall provide loop feed capability.

The minimum current carrying capabilities of components for the loop primary cable system shall be 200 amperes (continuous) and l0,000 amperes symmetrical (momentary).

(4) The low voltage terminals shall be in accordance with Figure 4(c) of ANSI C57.12.25-1990 and shall be externally clamped. The low voltage terminal stud bolts shall be copper, the neutral bushing stud bolt shall be provided with two (2) nuts on the stud.

(5) The low voltage neutral shall be a fully insulated bushing. A ground pad shall be provided on the outer surface of the tank. A removable ground strap, suitably sized for the rating of the transformer shall be provided and connected between the low voltage neutral bushings and the ground pad.

4.3 High and Low Voltage Compartment

(1) The high and low voltage compartment shall comply with ANSI C57.12.25-1990.

(2) The high voltage portion of the compartment shall contain the high voltage bushing wells and be provided with a cable accessory parking stand.

4.4 Accessory Equipment

(1) Accessory equipment shall be provided in accordance with ANSI C57.12.25-1990.

(2) Lifting provisions shall be of adequate strength and size to allow for the lifting of the complete transformer assembly when filled with oil and shall be arranged on the tank toprovide a suitable lift.

(3) Terminal designations shall be as shown in Figure 2 of ANSI C57.12.25-1990. The identification of the terminal connection shall be as shown on the instruction nameplate.

(4) An instruction nameplate shall be provided in conformance to ANSI C57.12.25-1990.

(5) All transformers shall have a 5/16" hole drilled at the top center of the transformer door. This hole shall be painted and covered to prevent access from the outside of the transformer. Note: This hole is to be used for the installation of a LED Indicator for a GRU installed Fault Indicator. (See Figure 1, this specification).

GRU

62602 R101 1

NO PCB's

5/16" hole and cover for LED Indicator (Hole drilled and cover by Transformer Manufacturer)

Hi-Lift Hood Handle

Page: T - 85.03

Gainesville Regional Utilities Electric System Approved Materials Manual

TRANSFORMER, SINGLE PHASE (PAD)

(TECHNICAL SPECIFICATIONS)

Revision Date:

9-22-15 KLC

5-4-18 KLC

4-5-19 KLC

6-4-19 KLC

7-29-19 KLC

M o r e t h a n E n e r g y

SM

ITEM NAME

(3) Each transformer shall be equipped with a non-resettable device which detects and provides external indication of internal transformer faults, and also incorporates pressure relief functionality. The approved device is manufactured by IFD Corporation or approved equal. This device shall be installed on the transformer and located within the Low-Voltage compartment.

An automatic pressure relief valve (Qualitrol Series 202 or equivalent) designed to relieve excessive internal pressures shall be installed on each transformer.

(4) Tank grounding provisions shall be as specified in ANSI C57.12-25-1990 for a type 2 arrangement.

4.7 Assembly and Enclosure Security

(1) The assembled unit shall meet the enclosure security provisions of ANSI C57.12.28 -2005, and be suitable for mounting on a concrete pad.

(2) The transformer door shall be fastened to the case with stainless steel hinges and hinge pins. The hinge pins shall be held in place by a mechanical stop which will allow removal of the door only in fully open position.

(3) Provisions shall be made for padlocking the cover when closed. A captive penta head bolt shall be provided for securing the cover. Locking provisions shall be recessed, in accordance with ANSI C57.12.28 - 2005.fully open position.

(3) Provisions shall be made for padlocking the cover when closed. A captive penta head bolt shall be provided for securing the cover. Locking provisions shall be recessed, in accordance with ANSI C57.12.28 - 2005.

4.8 Enclosure Coating System and Labels

(1) The enclosure coating system shall conform to the requirements of ANSI C57.12.28-2005.

(2) The finish coat shall be Munsell-7GY 3.29/1.5 padmount green. The paint thickness shall be a minimum of 2.5 mils.

(3) Transformers shall be provided with the following labels, designed for outside application, permanently affixed to the front of each unit (see figure 2, this specification):

(a) kVA rating label

(b) NEMA "Mr. Ouch" Warning Label, English/

Spanish bilingual, horizontal design.

(c) "No PCBs" label in conformance with

EPA 40 CFR Part 761.

4.9 Overcurrent Protection

(1) Each transformer shall be provided with an oil-immersed weaklink fuse designed to isolate the transformer in case of an internal failure.

(2) The weaklink fuse shall be attached to the H1A bushing well in a manner which will facilitate removal and replacement of the fuse by the action of unbolting and removing the bushing well through the tank wall.

4.10 Impedance

(1) The percent impedance (%IZ) as measured on the rated voltage shall be as follows:

kVA rating maximum %IZ minimum %IZ

25 through 75 3.00 1.50 100 through 167 3.00 1.60

(2) The tolerance for percent impedance shall be plus or minus 7.5% of the maximum %IZ value specified above, and not less than the minimum %IZ above.

NO PCBs

Note: Labels shall be located on the centerline of the Transformer Door.

Arrangement of Labels Figure 2.

75 (kVA Size)

Page: T - 85.04

Gainesville Regional Utilities Electric System Approved Materials Manual

TRANSFORMER, SINGLE PHASE (PAD)

(TECHNICAL SPECIFICATIONS)

Revision Date:

9-22-15 KLC

5-4-18 KLC

4-5-19 KLC

6-4-19 KLC

7-29-19 KLC

M o r e t h a n E n e r g y

SM

ITEM NAME

8. BID EVALUATION AND AWARD

8.1 All bids received will be evaluated and awarded on the

basis of conformance to this specification, the equivalent first cost and delivery. The Equivalent First Cost is the total cost of the transformer and shipping. The method used to determine equivalent first cost is documented in A Method for Economic Evaluation of Distribution Transformers, published by the Edison Electric Institute, April 1981.

8.2 The equivalent first cost shall be determined with the

following formula:

Equivalent First Cost (in dollars) = (7.93 x No load Losses in Watts) + (1.33 x Load Losses in watts) +Price

8.3 All bidders shall supply NO LOAD, LOAD and TOTAL losses on the form provided in the bid documents. All losses shall be quoted in watts at 20 degrees C. for No Load Losses and 55 degrees C. for Load Losses, per DOE, 10 CFR Part 431, Appendix A, Subpart K.

8.4 Quoted losses shall be the guaranteed average of all

transformers in a specific order of a given size and type.

However, no transformer shall measure less than the tolerances specified in the January 1, 2016, D.O.E. 10 CFR Part 431 minimum efficiency levels.

9. QUALITY CONTROL

9.1 Upon receipt, all transformers will be visually inspected by Gainesville Regional Utilities personnel to determine compliance with the specifications.

9.2 At the time of receipt the NO LOAD, LOAD and the TOTAL

losses will be measured by Gainesville Regional Utilities.

9.3 All losses quoted are the guaranteed average for all units contained in an order, however, no individual unit shall exceed the following tolerances:

(1) The measured NO LOAD LOSSES on any unit shall not exceed the quoted NO LOAD LOSSES by more than 10%.

(2) The measured TOTAL LOSSES on any unit shall not exceed the quoted TOTAL LOSSES by more than 6%.

5. TEST

5.1 Tests shall be performed in accordance with paragraph

4.2 and Section 5 of ANSI C57.12.25-1990.

6. TRANSFORMER EFFICIENCY

6.1 All Transformers shall meet or exceed the January 1, 2016, D.O.E. efficiency levels for liquid filled distribution transformers.

6.2 The efficiency levels shall be determined with the following formula:

% Eff = 100*(KVA*(0.5))/(KVA*(0.5) + NLL20 +

LL55*(0.5)^2)

6.3 D.O.E. January 1, 2016, Effiiciency Levels for Single Phase Transformers:

KVA DOE Rule (%)

25 98.95

37.5 99.05 50 99.11 75 99.19 100 99.25 167 99.33

7. CERTIFIED TEST REPORTS AND DATA REQUIRED

7.1 An approval drawing showing complete dimensional data, accessories and estimated weight shall be submitted for approval prior to fabrication.

7.2 At the time of delivery the manufacturer shall provide a

certified test report for all transformers in a given order, indicating the actual loss data for each unit delivered.

The certified test reports shall be included with the shipment, with an additional copy directed to the address in paragraph 6.3 of this specification.

7.3 Approval drawings and certified test reports shall be sent to:

Gainesville Regional Utilities Energy Delivery Standards P.O. Box 147117, Station E2-C Gainesville, FL 32614-7117

Page: T - 85.05

Gainesville Regional Utilities Electric System Approved Materials Manual

TRANSFORMER, SINGLE PHASE (PAD)

(TECHNICAL SPECIFICATIONS)

Revision Date:

9-22-15 KLC

5-4-18 KLC

4-5-19 KLC

6-4-19 KLC

7-29-19 KLC

M o r e t h a n E n e r g y

SM

ITEM NAME

Maximum Allowable Dimensions (inches) Figure 3.

10. NONCONFORMING TRANSFORMERS

10.1 Should any transformer fail to conform to the specifications in any way, the vendor shall replace the nonconforming transformer with a suitable transformer and bear all associated costs.

Radators shall not extend width or depth by more than 6 inches.

13" min. inside

TOP VIEW

FRONT VIEW SIDE VIEW

kVA A

25 - 75 24" 100 & 167 32"

31" min.

37" max.

42" max.10" min.

A max.