Site electrical review: before you add load
Circuits, breakers, and service capacity set a hard ceiling on mining at any site. Map what you have before buying machines — the answer is written on your panel, not in a forum.
Capacity math on your panel
A circuit delivers at most volts × amps: a 120 V / 15 A circuit tops out around 1,440 W usable (80% continuous rule); a 240 V / 30 A circuit around 5,760 W. Breakers trip on sustained loads above ~80% of rating — mining runs 24/7, so the continuous rule always applies.
| Circuit | Usable continuous (≈80%) | Hosts |
|---|---|---|
| 120 V / 15 A | ≈1,440 W | one mid GPU + headroom |
| 120 V / 20 A | ≈1,920 W | one big GPU rig, barely |
| 240 V / 30 A | ≈5,760 W | several ASICs / a GPU wall |
| Service entry 100 A @ 240 V | ≈19 kW whole-house | shared with everything else in your life |
Also check: service entrance capacity (the whole house budget), breaker availability, wire gauge and outlet condition, and whether the circuit is shared with anything that cycles (fridge, AC).
The review process
- List every load that will run simultaneously — miners, cooling, networking, plus the household baseline.
- Ask the utility for a service-capacity check if you plan to add more than ~20% of the panel rating.
- Licensed electrician for any new circuit or 240 V work — permits and insurance exist for a reason.
- Record the result: a one-page 'site capacity sheet' (circuits, amps, allocated watts) you update per expansion.
See it live on pow.family
Our project quick-starts note per-coin power envelopes from real rigs — multiply against your capacity sheet before purchase, not after.