Motor replacement guide
Find the right replacement motor
Answer five questions from your motor nameplate. We'll verify your amp rating, detect mislabeled HP, and surface the right replacement from our catalog.
Why your motor's labeled HP may not be accurate
Many air compressor motors are marketed at "peak" or "max" horsepower — a number the motor can briefly reach under ideal conditions, not what it actually delivers during normal operation. A motor labeled 5 HP that only draws 15 amps at 230V is, in practice, a 3 HP motor.
This is common with lower-cost imported motors and causes two problems: customers overpay for a replacement they don't need, or they buy a true 5 HP motor that their wiring and breaker can't safely support.
The amp rating never lies. Use it as your primary reference — the compatibility finder below does this automatically.
Labeled HP
5 HP
What the box says
May reflect peak or surge rating only
→
True HP
~3 HP
15A × 230V ÷ 746
What the motor actually delivers
How to read your motor nameplate
The nameplate is the metal tag attached to the motor housing. Here's what each field means and where to find it on the finder below.
COMPRESSOR SOURCE
Model CS-M1P230-30
PH
1
VOLTS
230
AMPS
17.2
HP
3
RPM
3450
FRAME
56
Hz
60
INS CL
B
Phase (PH)
1 = single phase, 3 = three phase. Must match your power supply.
Volts
If two voltages are listed (e.g. 115/230), select the one you're running.
Amps (FLA)
Full-load amperage — the most reliable indicator of true motor output.
HP
Horsepower as labeled. We'll cross-check this against your amp rating.
RPM
Most air compressor motors run at 1725 or 3450 RPM.
Frame
NEMA frame number (e.g. 56, 145T). Determines mounting dimensions.
Find your replacement motor
Answer five questions from your motor nameplate. We'll verify your amp rating against the labeled HP and surface the right replacement.
Step 1 of 5
What phase is your existing motor?
Listed on the nameplate as "1 Ph" or "3 Ph".
What is the voltage rating?
Check your nameplate for the voltage rating. Select the range that matches.
What is the full-load amperage (FLA)?
Why we ask this first: Some motors are labeled at a higher HP than they actually deliver. Your amp rating is the most accurate measure of true motor output — we use it to verify your motor's real HP before matching replacements.
HP, RPM, and frame size
All found on your motor nameplate. Common air compressor speeds are 1725 or 3450 RPM.
Frequently asked questions
Still not sure which motor you need?
Our team has decades of experience with air compressor motors. Give us a call or send a message — we'll help you get the right part the first time.