If you've spent any time in the electrical trade, you've almost certainly seen a copy of Ugly's Electrical References tucked into a tool bag or sitting on a job site table. Small enough to fit in your back pocket yet packed with essential data, Ugly's has been a trusted field companion for electricians, apprentices, and contractors for decades. Here's how to get the most out of it on the job.
What Is Ugly's Electrical References?
Ugly's Electrical References is a compact, spiral-bound quick-reference guide covering the most commonly needed electrical data in the field. It's not a code book — it doesn't replace the NEC — but it's the fastest way to look up critical numbers and formulas without flipping through hundreds of pages. The 2023 edition is updated to align with the NEC 2023.
Key content includes:
- Electrical formulas (Ohm's Law, power, current, resistance)
- Wire ampacity tables for copper and aluminum conductors
- Conduit fill tables (EMT, IMC, rigid)
- Motor wiring and full-load current tables
- Transformer connections and wiring diagrams
- Grounding and bonding requirements
- Common wiring diagrams (switches, outlets, 3-way, 4-way)
- Voltage drop calculations
- NEMA receptacle configurations
- Lighting and lamp data
Top Ways Electricians Use Ugly's on the Job
1. Wire Sizing and Ampacity
One of the most frequent field lookups is wire ampacity — what gauge wire can safely carry a given load. Ugly's ampacity tables let you quickly confirm the right conductor size for a circuit without pulling out the full code book. Always cross-reference with your local AHJ's adopted NEC edition for final compliance.
2. Conduit Fill Calculations
Ugly's conduit fill tables make it fast to determine how many conductors of a given size fit in a specific conduit type and size. The tables cover EMT, IMC, and rigid metal conduit across common trade sizes.
3. Voltage Drop Calculations
Long runs require voltage drop checks to ensure equipment operates within acceptable voltage ranges. Ugly's includes the voltage drop formula and a quick-reference table so you can calculate on the spot.
4. Motor Circuits
Ugly's full-load current tables for single-phase and three-phase motors — along with overload and short-circuit protection sizing guidance — are invaluable when sizing motor branch circuits in the field.
5. Wiring Diagrams
Ugly's clear wiring diagrams cover the most common residential and commercial configurations, saving time and reducing errors on straightforward installations.
6. Ohm's Law and Electrical Formulas
The Ohm's Law wheel and power formula tables in Ugly's are a quick sanity check for calculations in the field — useful whether you're sizing a circuit, troubleshooting a load, or explaining something to an apprentice.
Ugly's vs. the NEC: Know the Difference
Ugly's is a field reference, not a code compliance document. For final code compliance, always refer to the adopted edition of the NEC in your jurisdiction. That's why many experienced electricians carry both: Ugly's for speed on the job, and the NEC Handbook for code verification.
Get Ugly's Bundled with the NEC 2023
We offer Ugly's Electrical References bundled with the full NEC 2023:
- NEC 2023 Spiralbound + Ugly's Electrical References – ideal for field use
- NEC 2023 Hardcover Handbook + Ugly's Electrical References
- NEC 2023 Paperback + Ugly's Electrical References
Pick up your copy at BooksHarbour.com and never be caught without the numbers you need on the job.
