Section 13 — Electrical

Stationary Batteries and Battery Chargers

IPE Engineering Practice IPE-EP-13-9-1

Document number: IPE-EP-13-9-1 · Section: 13 — Electrical

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SCOPE

This Practice describes lead calcium, and Ni–Cad, type stationary battery sets that will be used to supply DC power to switchgear circuit breakers, electrical control power, synchronous motor field power, UPS, and instrument shutdown systems. This Practice also describes battery chargers to be used with battery systems for switchgear, electric control power, synchronous motor field power and instrument shutdown systems. NOTE: Chargers for use with UPS are covered in EP 13–17–1.

This Practice is appropriate for attachment to an inquiry or purchase document when accompanied by the referenced IPE Engineering Practices and completed Data Sheets.

Any deviation from this Practice must be approved by the procedure described in EP 1–1–3. A revision bar indicates all changes made to this Revision.

REFERENCES

The batteries and chargers shall be constructed and tested in accordance with applicable portions of the latest listed Standards and Codes. It shall be the Manufacturer’s responsibility to be knowledgeable of the requirements of these Standards and Codes. Any changes or alterations to the equipment to make it meet Standard and Code requirements shall be at the expense of the Manufacturer.

The latest edition of the following standards and publications are referred to herein.

STANDARDS AND PUBLICATIONS

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DEFINITIONS

Contractor – Company or business that agrees to furnish materials or perform specified services at a specified price and/or rate to the Owner.

Inspector – A Inflection Point Engineering, LLC appointed engineer or inspector.

Manufacturer - The recipient of a direct or indirect purchase order for materials and/or equipment. In this context, a direct order is one issued to a Manufacturer by a Contractor or the Owner. An indirect order is one issued to a Manufacturer by a vendor (recipient of a direct order) for materials, fabricated components, or subassemblies.

Owner – Inflection Point Engineering, LLC.

Owner’s Engineer – A Inflection Point Engineering, LLC appointed engineer.

Purchaser – The party placing a direct purchase order. The Purchaser is the Owner’s designated representative.

SERVICE CONDITIONS

The battery charger and battery shall be located in an environment as specified on the Data Sheet.

DESIGN, CONSTRUCTION & MATERIALS

Stationary Battery

Operating Duty for Switchgear Application

• During normal operation, the battery will be “floating” on the line with the battery charger connected. The normal steady state load, consisting of switchgear indicating lights, control power, synchronous motor excitation and others, will be as specified on the attached Data Sheet.
• The battery (based on 77ºF ambient) shall have capacity to supply the switchgear normal steady state load, for eight (8) hours with the battery charger off, and then trip and close all breakers in rapid succession, without discharging the battery below 1.75 volts (80% nominal) per cell for lead calcium, and 1.14 volts per cell for nickel cadmium. Tripping and closing loads are shown on the Data Sheet.

• Operating Duty for Instrument Application
• During normal operation, the battery will be “floating” on the line with the battery charger connected. The normal steady state load, consisting of shutdown relays and solenoid valves, will be specified on the Data Sheet.
• The battery shall have capacity to supply the normal load for eight (8) hours with the battery charger off without discharging the battery below 1.75 volts (80% nominal) per cell for lead calcium, and 1.14 volts per cell for nickel cadmium.
• U.P.S. Application: The battery shall have the capacity to supply the load for the time specified per EP 13–17–1 and associated Data Sheet, EP 13–17–1DS.

• Rating Lead Calcium Battery: The battery shall provide the rated voltage as shown on the Data Sheet and shall be designed for the ampere–hour capacity and short time discharge rates to meet the load duties as described above and on the Data Sheets.
• Construction of Lead Calcium Battery
• The cell shall be of the flat plate type. The cell plates shall be of a lattice grid type with the grid material being a calcium alloy. Negative plates shall have life equal to or greater than that of the positive plate.
• The cell shall be the sealed type, assembled in heat resistant, shock–absorbing (impact resistant), clear or semi–transparent plastic containers with covers cemented or welded in place to form a permanent leak–proof seal. Covers shall be supplied with flame arrestor vent plugs.
• The insulation between cell plates shall consist of microporous separators combined with molded–one–piece plastic spacers to provide correct spacing between the positive and the negative plates and to permit free circulation of electrolyte. The microporous material shall be ribbed on the side facing the positive plate.
• Elements shall be suspended either from ledges molded in the jar/container walls or from the covers.
• All cell terminals shall have adequate current carrying capacity and shall be made of lead alloy or lead–alloy reinforced with copper core inserts. Cell terminal posts shall be equipped with acid–resisting stainless steel connector bolts and nuts.
• Cell posts shall be sealed against creepage of electrolyte either by burned–ring seals, by lead–alloy seal nuts, or by plastic seal nuts.
• Cells shall have sufficient electrolyte to provide for full capacity at all ratings when the cells are fully charged.
• Sufficient sediment space shall be provided so that the cell will not have to be cleaned out during its life.
• Electrolyte level lines shall be marked on all four sides of each jar or container.
• The cell shall be delivered filled with electrolyte and fully charged.
• Lead–plated copper intercell connectors shall be supplied to provide 1/2 inch spacing between cells or units when installed with the plates at right angles to the rack rails.
• Rating of Nickel Cadmium Battery
• The battery shall provide the rated voltage and ampacity (amp hour) as shown on the Data Sheet.
• The discharge–rate family of battery supplied shall properly match the specified load profile. The choice of discharge–rate family shall optimize performance, service conditions and cost.

• Construction of Nickel Cadmium Battery
• The cell shall be of the pocket–plate type construction. The pockets shall be made with finely perforated nickel plated steel strips formed into channels into which the active materials of the plates are placed. The plate crimps and perforations shall be of proper tightness and size to prevent shedding of any active material.
• Sintered–plate cell construction is not acceptable.
• The cell shall be the sealed type, assembled in heat resistant, shock–absorbing (impact resistant), clear or semi–transparent plastic containers with covers cemented or welded in place to form a permanent leak–proof seal. Covers shall be supplied with flame arresting vents which are constructed to also restrict the entry of air into the cell.
• Terminal posts shall be of nickel–plated steel, or equivalent, to prevent corrosion. All cell terminals shall have adequate current carrying capacity.
• Cell plate shall be sealed against creepage of electrolyte either by buried–ring seals, or by plastic seal nuts.
• Plate separators shall be made of molded high–impact resistant plastic ribs to prevent shortcircuiting or reversing if the cell is subjected to severe shock or vibration.
• Sufficient sediment space shall be provided so that the cell will not have to be cleaned out during its specified service life.
• Electrolyte level lines shall be marked on all four sides of each jar or container.
• Cells shall have sufficient electrolyte to provide for full capacity at all ratings when the cells are fully charged.
• Cells shall be delivered filled with electrolyte and fully charged.
• Cells shall be individual units, one cell per case.
• Battery Accessories: “Sets” of battery accessories shall be furnished with each battery. Each “set” shall contain the Manufacturer’s recommended equipment required for maintenance and testing of the batteries. Each “set” shall contain, but not be limited to:
• One (1) portable hydrometer syringe
• One (1) hydrometer holder
• One (1) vent–mounted thermometer
• One (1) lot of anti–corrosion grease
• One (1) set of stick on cell numbers
• One (1) set of maintenance tools and supplies including:
• lead plated copper inter–cell connections and
• compression type lugs for inter–tie cables
• Battery Rack

A heavy duty battery rack with rails suitable for shock protected Zone 1 conditions shall be furnished for the battery. The length and depth of the overall assembly shall be a minimum practical size. The rack shall be coated/covered with a material that is resistant to any corrosion effects resulting from spilled electrolyte. The rack shall be sized to accommodate the specified number of cells and one future end cell. Arrangement shall be based on space available as indicated on the Data Sheet and/or drawings.

• Automatic Battery Charger
• General Requirements

• A fully automatic charger, silicon controlled rectifier (SCR) or controlled ferroresonant type, shall be furnished for each set of batteries. The charger continuous capacity and rating shall be adequate for the normal operating duty as described, and for charging the batteries from “no charge” to “full charge” within 24 hours (high charge rate) while supplying the normal load.
• The charger shall have separate float and equalize voltage control adjustments provided by two front panel mounted potentiometers. The equalize function shall be controlled via a 0–72 hour fully automatic equalizing timer that is front panel mounted. The timer shall function as the float equalize switch with the charger automatically returning to float at the end of the time interval.
• The circuitry shall be such that: (i) under normal conditions the batteries will receive trickle charge; (ii) on extended loss of input power source, and after a preset time period to verify restoration of supply, the batteries will receive equalize/boost charge for the time period set by the equalizing timer; and (iii) after this set time, the charger will automatically revert to float mode. It shall also be possible to set the equalizing timer manually.
• Metering
• DC output ammeter – ± 2% accuracy and a minimum scale length of 2–1/2 inches.
• DC output voltmeter – minimum of 1000 OHMS per volt with ± 2% accuracy, a minimum scale length of 2–1/2 inches.
• AC power input voltmeter.
• D.C. Ground Detection
• Provide a ground detection voltmeter to measure positive to ground, and negative to ground. Control to be a switch (maintained in off) with positive to ground (momentary spring return to off), off, and negative to ground (momentary spring return to off).
• Provide two push to test ground indicating lights (white/clear) connected positive to ground and negative to ground.
• When specified on the Data Sheet for battery eliminator option, provide additional filtering to allow the charger to operate into connected loads without the battery. The charger in the eliminator mode shall have an output ripple less than 30mV RMS.
• The charger shall have its DC output voltage maintained to ± 1/2% or less for changes in rated line frequency of ± 5% , in rated line voltage of ± 10%, and in load from 0 to 100% of rated. The charger shall maintain ± 0.5% or better regulation for combined variations of line, load, and frequency, as specified above, as well as temperature (32oF to 104ºF).
• Alarms: The following separate alarms shall be provided:
• Low DC voltage alarm
• Input AC failure alarm
• Charger failure alarm (loss of DC output current)
• Ground detection alarm
• High DC voltage alarm
• All alarm contacts shall be either separate form C contacts or have a separate N.O. contact (contact opens to alarm). Contacts shall be rated 5 ampere or higher at 125V DC.
• Charger efficiency at full load shall be greater than 85% at nominal input and float output.

• Automatic current limiter adjustable from 90% to a maximum of 120% of the rated output current, factory preset at the Manufacturer’s standard not to exceed 120%.
• The charger input supply voltage shall be as specified on the Data Sheet.
• The equipment shall be capable of supplying maximum rated output continuously without exceeding the temperature limitations of the materials used in its construction.
• Output Voltage Ripple: Ripple when charger is connected to a battery with an 8–hr amp–hr rating of 4 times the full–load current rating of the charger.
• Unfiltered:
• Single phase: less than 10% RMS
• Three phase: less than 3% RMS
• Filtered: Single and three phase: less than 30mV RMS
• The charger shall have surge withstand capability to meet the requirements of ANSI C37.90.1– 1974/IEEE Std 472–1974.
• If specified on the Data Sheet, the charger shall be capable of parallel operation with either 1 or 2 other duplicate chargers. The charger shall be provided with load sharing circuitry, to assure equal load sharing operations within ± 10% .
• The charger shall be capable of supplying the entire load and simultaneously recharge the battery bank in 24 hours after battery has been 100% discharged.
• The following items shall be provided as additional required features:
• AC line circuit breaker with interrupting rating as specified on the Data Sheet.
• 2 pole DC load circuit breaker.
• Automatic surge suppressors.
• Hermetically sealed silicon controlled rectifiers.
• AC power failure relay. The relay shall isolate control section upon AC line failure. Coil of relay shall be connected on load side of AC breaker.
• The charger shall be so designed that in event of charger output failure, with AC line voltage connected, backfeed from external DC bus will not damage charger components.
• AC pilot light - charger on (push to test light).
• Internal terminal boards for connection of AC input, DC output and remote intelligence circuits.
• The equipment shall be completely assembled and wired in a free–standing or wall mounted cabinet suitable for indoor installation. The cabinet shall be arranged for front operation and maintenance. Removable side panels may be provided, but rear access will not be available. Provision shall be made for Owner’s conduit entrance at top and bottom. Adequate ventilation shall be provided. The cabinet shall be cleaned, primed, and painted with a minimum of two coats of paint or one coat of powdered baked epoxy, color ANSI 61 or Manufacturers standard color.
• Permanent plastic nameplates shall be provided to identify each instrument, switch, relay and meter. Nameplates shall be plastic lamicoid tags with black letters on a white background and fastened with screws.

• Electrical Protection
• SCR’s, diodes, and circuits used in the battery charger shall be protected by high speed semiconductor fuses and suitable surge suppressors. The design shall incorporate protection against internal and external short and open circuits and overloads imposed on the equipment.
• Terminals that are live with multiple unit feeds from more than one power source shall be identified and properly shielded to avoid shock hazard. Furnish danger sign indicating multiple power feeds.
• Electrical Interference: Operation shall not generate electrical noise or be affected by electrical noise.
• Wiring
• All wiring shall be flame retardant. Control wire shall be #18 AWG or larger and #8 AWG or larger for DC bus, 600 volt insulation, type TBS, cross linked polyethylene insulation, or SIS insulation.
• Extra flexible cable shall be used between stationary and hinged panels.
• All wiring shall be suitably protected against contact with sharp edges, neatly bundled and secured with wire ties.
• All wires shall be permanently marked at both ends to agree with the wiring diagrams. The preferred method is to use plastic sleeves, such as shrink tubing, stamped with the entire wire number or Brady slip on. Adhesive type wire labels shall not be used.
• Terminal lugs shall be compression type with insulated sleeves and spade or ring type lugs.
• Terminal blocks shall be suitable for holding spade or ring type lugs.
• Connection points for Owner’s wires shall be clearly identified in the equipment and on the wiring diagrams.

TESTING

• In addition to the Manufacturer’s standard tests, the Manufacturer shall also perform the following tests:
• Full functional test of all alarms and verification of all limit settings.
• In accordance to NEMA PV–5:
• Dielectric
• Voltage adjust
• Voltage regulation
• Current limit
• Ripple voltage

6.2 When a witness test is specified, the Owner shall witness the complete testing of all items detailed in Paragraph 6.1 and the contract documents.

DRAWING AND DATA REQUIREMENTS

All drawings provided for this equipment shall show equipment as specified and ordered, typical drawings are not acceptable. Drawings shall be supplied in the quantities and format shown on the Data Sheet.

• Information to be Supplied with Quotation
• Performance curves, as applicable, Manufacturer’s prints, and other descriptive data, including dimensions, as required for a complete description of the equipment proposed. The Manufacturer shall furnish heat gain for each battery charger.
• Complete lists of all equipment and accessories proposed. Components not manufactured by the Manufacturer submitting the proposal shall be so noted as well as the Manufacturer and type proposed.
• Bulletins completely describing the battery and charger.
• Maximum charger input power requirements during the highest charge rates.
• Overall dimensions and weights of battery and rack assembly.
• Outline dimensions and wiring diagrams of the charger.
• Itemized list of battery accessories.
• Recommended values for high rate charging of the battery and optimum time required to fully charge battery from a fully discharged condition.
• The proposal shall include a complete list of unit prices consisting of the cost to add or delete each item.
• The manufacturer shall state in the proposal all exceptions to this Practice or shall state that no exceptions are taken.
• Priced lists of normally recommended spare parts for the specified equipment shall be included in the quotation.
• Hydrogen production rate per cell during heavy equalize charge, and normal float charge.
• Maximum (peak) noise level from the charger in worst case mode measured at 3 feet from the charger.
• Itemized listing of standard production tests that shall be performed and, when specified, witnessed by the Owner. Itemize additional testing available as an option. Provide itemized cost for standard and non–standard tests as well as cost for witness test.
• Provide conversion efficiencies and power factor at 10, 60 and 100 percent of rated output with nominal AC input voltage and frequency.
• Information to be Submitted to the Owner for Approval After Receipt of Order
• The Manufacturer shall furnish plan and elevation drawings of the equipment indicating outline dimensions, weights, space for Owner’s conduit entrance, terminal locations, minimum recommended clearances, support and hold down requirements.

• Elementary (schematic) control diagrams shall be furnished indicating all control devices and contacts with ANSI device function numbers.
• Wiring diagrams shall indicate all interconnecting wiring and the approximate physical location of devices in assembly. All terminal blocks and wires shall be clearly labeled. The minimum drawing size 11 x 17 inches. Tabular wiring diagrams are not acceptable. Wiring diagrams shall be destination address type.
• Elevation and section views showing locations of internal components and terminals as well as overall dimensions.
• Listing of recommended battery specific gravity and voltage per cell at full charge, 75% charge and 50% charge.
• Cell temperature de–rating charts/curves.
• Complete details for load discharging and testing the batteries include test procedure, acceptance criteria, and recommended intervals for this type of testing.
• Certified Information to be Submitted
• All information requested in Section 7.2 of this Practice.
• Installation, Maintenance and Operating Instructions: Installation and operating instructions shall cover all the equipment furnished.
• Material List: A material list shall be furnished listing the quantity, rating, type, and manufacturer’s catalog number of all equipment.
• Test Reports as required for testing as identified in this Practice, the Data Sheets and other purchase documents.
• Spare Parts Listing

SPARE PARTS

A complete spare parts recommendation based on the total purchase order is required within 60 days after the Manufacturer receives the purchase order. Spare parts recommendations shall include:

• A complete spare parts list, including parts location diagrams or drawings.
• Lists of priced spare parts as recommended by the Manufacturer to be on hand during plant start–up and the first year’s operation.

PREPARATION FOR SHIPMENT

• “Preparation for Shipment” shall be in accordance with Manufacturer’s standards, unless otherwise noted on the “Request for Quotation” and/or “Purchase Order”. The Manufacturer shall be solely responsible for the adequacy for the “Preparation for Shipment” provisions employed in respect of materials and application, to provide materials to their destination in ex– works condition when handled by commercial carrier systems.
• Each shipping box shall be provided with a weatherproof tag stating the Purchase Order number.

• Include with the shipment: Battery and battery charger instruction books, specific gravity, initial cell charge rate and volts per cell data taken at the factory prior to shipment.
• Any equipment/accessories that need special handling or storing shall be clearly identified with appropriate labeling.

10.0 TABLES

TABLE 1

CERTIFIED INFORMATION REQUIRED IN ELECTRONIC FORMAT for STATIONARY BATTERIES PER EP 13–9–1

TABLE 2

CERTIFIED INFORMATION REQUIRED IN ELECTRONIC FORMAT FOR STATIONARY BATTERY CHARGERS PER EP 13–9–1

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