HDE, LB-5, Dual Voltage Load Box, 240/120V and 480/277V
The LB-5 Load Box helps to prevent the damaging effects of ferror esonance found on lightly or unloaded 3-phase power systems. This situation typically occurs on medium voltage distribution transformers and power cables during single phase switching. Asthe electric power industry move stowards more efficient transformer design, this condition is becoming more common. If such conditions exist, over voltage can lead to the breakdown of insulation resulting in damage to the transformer, lightning arresters and other equipment. When using the LB-5 to connect and apply a resistive load on the transformer secondaries, damage to distribution equipment due to ferror esonance can be prevented.
Features
- Helps prevent ferror esonance during single phase switching
- Portable, one person design
- Dual voltage, auto voltage selection
- Powered by transformer secondaries 120/277VAC
- 5,000 watt per phase loading
- Resistive load up to 3 phases
- 40A fused disconnect switch
- Blown fuse indicator lamp
- Auto-ranging voltage input – no switching required
- Operating frequency of 50/60Hz
Application
Proper application of the Load Box helps prevent ferror esonance on power distribution circuits. Ferror esonance can cause over voltages and over currents in an electrical power system that can damage circuit components such as transformers, capacitors and lightning arresters and endanger personnel. The sustained over voltages caused by ferror esonance damage lightning arresters by overheating and blow fuses in nearby capacitor banks. These over voltages also drive transformer cores into saturation resulting in current surges through the distribution circuit and when sustained, can cause permanent damage to transformers.
