This article is about material checking and technical design requirement of Vented Lead-Acid Wet Cell for commercial buildings, plants and refinery projects.
Vented Lead-Acid Wet Cell Material Selection & Checking
| QC Before Installation- Vented Lead-Acid Wet Cell shall conform to all applicable requirements, standards, and specifications prior to release to be used as part of work. |
| Incoming Vented Lead-Acid Wet Cell shall be visually inspected for damage / defects occurred during transportation and conformance to all applicable requirements. |
| Vented Lead-Acid Wet Cell shall be new and unused. |
| Vented Lead-Acid Wet Cell shall be in accordance with the approved project-specific design drawings, diagrams, schedules, lists, databases, and associated design documents. |
| Check that the Contractor or it’s Saudi Aramco approved third party inspector performed the quality activities at the supplier and sub-supplier locations as required by the inspection level assigned for the materials and equipment identified in Inspection Requirements. |
UPS/DC Vented Lead-Acid Wet Cell Design Application Notes & Technical Requirements
| The design life of Vented Lead Acid batteries shall be at least 20 years. The cell shall be considered to have reached the end of its useful life when the ampere-hour capacity drops to 80% of the rated capacity at the 8/10 hours discharge rate for lead-acid batteries. |
| The shelf life of Vented Lead Acid batteries shall be minimum 2 years when stored at 35°C room temperature. |
| The manufacturer shall provide a pro-rated warranty for 20 years from the date of commissioning, including full free replacement guarantee during the first 3 years of service, either as a cause of defective workmanship, or if the battery fails to deliver its rated capacity |
The battery shall have the following minimum cycle-life capability (1000 cycles) during its lifetime at the 1-hour discharge rate, at 25ºC. The cyclic performance is stated in terms of the number of full charge/discharge cycles that the cell can sustain during its useful life.
Ampere-hour capacity of the new cell shall be indicated by the manufacturer on Data Schedule-2. This data shall be provided for C8 or C10 for lead acid batteries, at 25°C, to the final voltage (end-of-discharge voltage) between 1.65 VPC and 1.75 VPC for lead-acid batteries.
Battery sizing and selection shall be based on the following minimum volts per cell between 1.65 to 1.75 VPC for general applications and 1.85 VPC for PV applications.
| All connections shall be bolted to the cell posts. All cell-to-cell connections shall be made by insulated copper cables or plated copper bus bars using 316 stainless steel hardware. Tier-to-tier connections shall be made by insulated copper cables with 316 stainless steel hardware. The cell-to-cell interconnecting hardware shall be sized to allow discharge current at the 30-minute rate with no more than 15 mV drop between adjacent cells. The inter-cell connectors shall withstand the available short circuit current without damaging the unit. Covers for the inter-cell connecters and the terminals shall be supplied with the batteries. |
| All nuts, bolts, washers, and similar hardware shall be 316 stainless steel or nickel plated copper or equivalent. |
| Vented lead-acid cells shall meet the design, performance, and test requirements of IEC 60896-11. |
| Lead Acid Batteries: A battery with an aqueous electrolyte based on dillute sulfuric acid, a positive electrode of lead dioxide and a negative electrode of lead. |
| The plate design (either tubular or pasted plate, lead-calcium or lead-antimony alloys) shall be as specified on Data Schedule-1. Lead-antimony alloys shall not contain more than 2% antimony. Commentary Note 8.2: Other plate designs and alloys would be given consideration after their performance characteristics have been reviewed and approved by the Electrical Standards Committee Chairman for the intended application. |
| The cell design shall accommodate the total positive plate growth during the design life of the cell. The plate growth shall not cause cracking, deformation, or failure during the lifetime of the cell under normal operating conditions. |
| Cell containers and covers shall be made of a high impact plastic material. The cover shall be permanently attached to the container to form a leak-proof seal. |
| Each cell shall have provisions for indicating the minimum and maximum electrolyte levels. For transparent and translucent containers, the minimum and maximum levels shall be permanently marked on each cell container. A level indicating gauge shall be provided on cell containers made of an opaque material. |
| Electrolyte level readjustment period, under float conditions, shall be at least one (1) year. |
| Terminal posts shall be lead alloy. Cells larger than 150 ampere-hours capacity, at 8/10 hour discharge rate, shall have lead plated copper posts or have a copper or brass core insert for providing a reliable low-resistance interface with the inter-cell connectors. Covers for the inter-cell connecters and the terminals shall be supplied with the batteries. |
| Flame-arrestor type vent plugs shall be provided to minimize the possibility of internal battery explosion caused by an external spark or battery room fire. The vent plug shall prevent any visible wetting of the cell lid when the cell is being overcharged at the equalizing voltage at 25°C ambient temperature. |
| Racks shall be constructed of welded or bolted structural steel frames with bolted steel runners and braces, and with provision for anchoring to the floor and grounding. |
| Battery rack shall consist of up to 2 steps, and each step shall have only one row for the ease in maintenance. The maximum height from the floor level to the top terminal of the upper battery shall be 1700 mm, which may allow up to 2 tiers rack. |
| All metallic rack components that are in contact with the battery shall be insulated by removable covers or the rack shall be plastic coated. |
| All metallic components of the rack, excluding hardware and grounding connectors, shall be coated with plastic or acid resistant baked powder epoxy of light gray or black color. Racks for nickel-cadmium batteries shall be coated with an alkali-resistant plastic coating of light gray or black color. Where applicable, Vendor shall supply sufficient quantity of field-applied coating for touching up scratches. |
| Indoors Mounting: Battery enclosures and cell supports shall be free-standing and made of fiberglass reinforced material or steel and conforming NEMA 250 Type 1, or IEC 60529 IP 21. The battery enclosures shall have suitable ventilation with provisions for anchoring to the floor and grounding. |
| Outdoors Mounting: Battery enclosures for outdoors mounting applications shall be completely weather-proof, dust-tight and rain-tight. Minimum enclosure protection class shall be NEMA 250 Type 4, or IEC 60529 IP65. The battery enclosures shall be made of fiberglass-reinforced material, with suitable ventilation and provisions for anchoring to the floor and grounding. |
| The following accessories shall be furnished with each new and complete battery system. a. Thermometer for measuring cell electrolyte temperature b. Hydrometer c. Bottle or filling jar with pour spout for adding distilled water d. Ample supply of NO-OX terminal grease e. All required intercell and inter-row connectors with covers f. Cell /battery module mechanical lifting device and slings for installation and removal of cells and modules weighing more than 34 kg (75 lb.) |
| Replacement cells shall be provided with terminal grease, cell connectors, and connection hardware. Covers for the inter-cell connecters and terminals shall be provided with the batteries. |
| The following information shall be permanently marked on each cell or multi-cell module: a. Manufacturer’s name. b. Manufacturer’s catalog number or type reference. c. Capacity (as described in Section 7.5) d. Electrolyte density (fully charged at 25°C) – not required for VRLA batteries. e. Date of manufacture. f. Electrolyte level markings (as described in Section 8.5). |
| Vented lead-acid cells shall be shipped in dry charged condition (without electrolyte). As part of the battery, local representative of the battery manufacturer shall supply the electrolyte and fill the battery. |
| Individual cells shall be packed to provide protection against physical damage and moisture. |
| Shipping crates shall be marked with handling and storage instructions. Labels on the shipping crate shall state the storage conditions, date of shipment, and the date beyond which the product must not be stored. |
| Instruction Manuals, Each complete battery system shall be provided with instruction manual(s) including the following information as a minimum. The required number of sets shall be as specified in the Purchase Order. a. Factory testing is not required for flooded lead-acid and nickel-cadmium batteries. b. Installation & commissioning instructions c. Required purity of the topping-up water and the electrolyte d. Operating instructions e. Maintenance instructions and the required maintenance schedule f. Testing instructions and the recommended frequency of tests g. Clearly identified warnings shall be provided in the documentation for conditions where improper action by an operator would create a safety hazard or damage the battery and associated equipment. |
| If batteries are to be delivered to the Buyer in a fully charged condition, the Vendor shall recommend a method of maintaining the battery in charged condition until the battery is commissioned. Detailed instructions & required equipment shall be provided for dry charged batteries requiring on-site activation. |
Check that the Cells are supplied from the approved manufacturer as per Regulated Vendors List for Electrical Equipment. SAES-P-101, SAES-P-101
UPS/DC Vented Lead-Acid Wet Cell International Codes and Standards
| 17-SAMSS-511 Stationary Storage Batteries |
| SAES-P-101 Regulated Vendors List for Electrical Equipment |