Backup Power Glossary
Watts describe instantaneous power, watt-hours describe stored energy, surge watts cover motor startup, voltage determines compatibility and transfer equipment determines safe household connection.
Complete guide covering backup power glossary, including features, real-world uses, sizing, safety considerations, and buying advice.
What Matters Most
Watts describe instantaneous power, watt-hours describe stored energy, surge watts cover motor startup, voltage determines compatibility and transfer equipment determines safe household connection.
Editor's Verdict
Watts describe instantaneous power, watt-hours describe stored energy, surge watts cover motor startup, voltage determines compatibility and transfer equipment determines safe household connection.
Watts and Watt-Hours
A watt measures power at a moment. A watt-hour measures energy used or stored over time. A 100W load running for five hours uses 500Wh.
Battery Terms
State of charge is the estimated remaining percentage. Depth of discharge is the portion used. Cycle life is the number of equivalent full cycles before capacity falls to a stated level.
Inverter Terms
Pure sine wave describes smooth AC power. Continuous output is sustained wattage. Surge output is short-duration peak power.
Generator Terms
Running watts describe continuous output. Starting watts cover brief motor-start demand. Dual-fuel and tri-fuel describe supported fuel types.
Solar Terms
MC4 is a common locking PV connector format. MPPT optimizes solar harvesting. Open-circuit voltage is panel voltage with no load.
Installation Terms
A transfer switch safely selects utility or backup power. Backfeeding is a dangerous improper connection that can energize utility lines.
Buying and Safety Checklist
Confirm Compatibility
Use the exact model, voltage, connector, dimensions and rating.
Check Electrical Limits
Do not exceed source, outlet, cable or accessory ratings.
Review Installation
Follow current manufacturer instructions and applicable electrical requirements.
Inspect Before Use
Do not use damaged, wet, overheated or poorly fitting equipment.
Frequently Asked Questions
What is the difference between watts and watt-hours?
Watts measure power; watt-hours measure energy over time.
What are surge watts?
Short-duration power available to start motors and compressors.
What is usable capacity?
Energy available after reserves and conversion losses.
What is pure sine wave?
Smooth AC output similar to utility electricity.
What is MPPT?
A charge-control method that optimizes available solar input.
What is a transfer switch?
Equipment that safely selects utility or backup power for circuits.