Load Bank Specifications LOAD BANK CONNECTIONS Most Avtron load banks are three-wire delta designs. Four wire wye power systems can be easily connected to the standard Avtron load bank by connect ing phases A, B, and C to their respective input terminals. The standard Avtron load bank is a balanced 3-phase load, so the gen- erator’s neutral wire is not required. Load Bank Buyers Guide When rating load bank capacities for special applications, refer to the wiring 60 hz models diagrams shown on right. POWER INFORMATION The KW rating of the engine-generator set is dependent on the horsepower rating of the prime mover and the electrical rating of the generator. The KVA rating of the generator is dependent on the current rating of the generator. ORDERING When ordering or requesting pricing on Avtron load banks, the following inform ation is helpful: 1. Resistive, Reactive, or DC 2. Applied Voltage(s) and Frequency 3. Portable or Permanent Mounting 4. Capacity VOLTAGE DERATING 5. Load Step Resolution Load banks are designed to provide 6. Internal and/or External Control a specific capacity at a rated voltage. Power They cannot be operated at a volt- 7. Blower Voltage Requirements age higher than their rating without 8. Indoor or Outdoor Service risking damage to the load bank. 9. Core Dimensions and Air Flow However, the load bank can be (K711 Duct Mount only) operated at lower voltages. For a prompt quotation, please pro- Load bank derating is calculated as vide a complete specification via Fax: follows: (216) 573-5953, Phone: (216) 573-7600, or e-mail: [email protected]. Communicator EXT™ is a trademark of Electro Industries/GaugeTech. • ADMS™ and Helidyne™ are trademarks of Avtron LoadBank, Inc. • Windows™ is a trademark of Microsoft Corp. Specifications and features are subject to change without notice. Quality System Certified to ISO 9001 www.avtronloadbank.com 6255 Halle Drive • Cleveland, Ohio, U.S.A. 44125-4615 • 216.573.7600 • FAX 216.573.5953 www.avtronloadbank.com • [email protected] Bulletin 296 • Rev. G power test solutions Avtron LoadBank, Inc. Medium Voltage Load Banks Since 1953, Avtron has been a Avtron Load Banks are devices designed to provide electrical loads for Avtron is a leading manufacturer of true medium voltage load banks. are standard. Other voltages are also leader in the design and manufacture testing power sources such as generators and Uninter r­­uptible Power Supplies These units operate at the actual output voltage of medium voltage generators available as custom designs. of high quality and reliable products (UPS). Load banks are also used to reduce “wet stacking” problems in diesel and therefore do not require large step-down transformers. Also available are conventional load intended for very demanding indus- engines of backup generating systems. A typical module is rated 4 to 6 megaw atts and multiple modules are used bank and step-down transformer trial applications. Avtron’s products de signs (model K875A-MV) mounted Most Avtron resistive load banks when tens or hundreds of megawatts are required. Voltages from 5 to 15 kV include: on a common structural skid. feature Helidyne™ resistive ele- • Resistive and Reactive Load Banks ments. These Avtron de signed and • Industrial Resistors manufactured elements are made of • Aircraft Electrical Test Systems a corrosion resistant chromium alloy • Digital Instrumentation Systems and are fully supported across their AVTRON NEUTRAL • Digital Control Systems entire length on stainless steel sup- GROUNDING RESISTORS Avtron is 100% committed to main- port rods with segmented ceramic Avtron Neutral Grounding Resistors taining the high standards that you insulators. Elements are carefully are designed to provide added safety have every right to expect – in selected to operate at low tempera- to industrial distribution systems by Design, Manufacturing, and tures to provide extended, reliable Avtron’s Helidyne™ elements are fully sup- limiting ground fault current to rea- Product Support. performance, eliminating the need ported and operate at low temperatures for sonable levels. In a typical solidly for a “cool down” period after load Model K922A is one of several medium voltage Decades of extensive experience longer life. grounded four wire system, the neu- bank operation. modules used by a large turbine manufacturer provide Avtron with capabilities for production testing. tral is tied directly to earth ground. for satisfying any load bank Skid mounted medium voltage load bank system is cost This can cause high ground fault cur- design requirement. APPLICATIONS effective, available from 750 to 2000 KW (model K875A-MV). rent (typically 10,000 to 20,000 amps) and excessive damage to transform- Load banks can be used in a wide • Load optimization in prime ers, generators, motors, wiring, and variety of applications, such as: power applications Radiator and Duct Mounted associated equipment. Inserting an • Factory testing of engine • Factory testing of turbines Load Banks Avtron Neutral Grounding Resistor QUALITY SYSTEM generator sets Avtron manufactures both the load between neutral and ground limits • To reduce “wet stacking” banks and the auxiliary equipment fault current to a safe level (typically CERTIFIED TO ISO 9001 problems necessary to handle these and other The Avtron model K711 and K711A load banks are designed for radiator or duct 25 to 400 amps) while still allowing Avtron’s Quality System is certified • Periodic exercising of stand-by applications. Contact your Avtron mounting on diesel engine generator sets. The load bank is permanently mount- sufficient current flow to operate fault to meet ISO 9001 standards. This engine generator sets sales representative for complete ed to the front of the engine generator and sized to match the width and height clearing relays. Limiting fault current means that Avtron products con- • UPS system testing support in choosing the best load of the radiator core or exhaust duct opening. The load bank utilizes the engine also reduces the problem of transient sistently meet the highest quality • Battery system testing bank system for your requirements. cooling air rather than an internal overvoltages (up to six times normal standards. • Ground power testing cooling fan found on conven- voltage) which can occur during arcing tional load banks. A top and type ground faults. MEET NFPA bottom mounting flange, or Internal bushings/connection points IMPROVE RELIABILITY OF GENERATOR SET removable duct adapter flanges eliminate the need for elevating REQUIREMENTS are supplied for mounting and stands or towers to raise live roof Industry trade organizations and manufacturers both agree that a well planned ease of installation. bushings above personnel. Current The National Fire Protection Assoc- preventive maintenance program is vital to the reliable operation of a standby transformer (to monitor fault current) iation (NFPA) has issued testing generator. Load Banks are an essential part of such a program. Load Banks pro- The load banks are typically sized are available as an option. stand ards for emergency and stand- vide a practical means to test the system without interruption to the critical loads. at 50-60% of the generator KW by power systems including NFPA 70, rating and used to periodically NFPA 99, and NFPA 110. These stand- The primary cause of diesel engine failure is “wet-stacking” (“wet” unburned test the generator or to supple- ards provide guidelines for installa- fuel accumulating in the engine “stack”). It is caused by under-loading of the gen- ment the real generator load to tion acceptance of power systems, erator. Diesel engines that are lightly loaded, or allowed to idle for long periods, minimize the effects of diesel periodic testing and maintenance, never reach their recommended operating temperature. Over time, unburned fuel engine “wet-stacking”. and specific testing requirements of coats the combustion chamber, reducing engine rating, efficiency, and life span. Capacities range from 10 to 1000 systems used to support health care A preventive maintenance plan that includes load testing of a diesel generator KW at voltages of 208, 240, or facilities. All these standards require set, will reduce the harmful effects of “wet-stacking” and increase engine life. Radiator and duct mounted load bank 480 volts AC, 3-phase, 60 Hz. from 10 to 1000 KW (model K711). partial or full load testing of backup power systems using loading equip- ADVANTAGES OF ALUMINIZED STEEL CONSTRUCTION ment. Avtron load banks provide Load Banks convert electrical energy into heat. The majority of this heat is the necessary loading capabilities dissipated away from the device by the cooling fan. However, the enclosure for testing emergency and standby itself absorbs a portion of the generated heat. As such, these products must power equipment to meet NFPA be constructed out of a material that can withstand this thermal environment. Neutral Grounding Resistor rated requirements. Avtron Load Bank enclosures are constructed from Aluminized Steel, which 4160/2400 volts, 400 amps, 10 seconds. offers superior heat and corrosion protection over the more commonly used Galvanized Steel. 2 7 Reactive Load Banks 60 Hertz Standard Models Avtron inductive/reactive load banks (KVAR) are typically Models such as the K841 and K841B range from 50 to 1875 Model Capacity Min. Load Step Load Voltage Blower Voltage Dimensions Weight Resolution (approx. inches) (approx. pounds) used in combination with resistive load banks (KW) to test KVAR. They