Aerovox Capacitor Cross-Reference Guide
Aerovox Corporation ceased independent operations after a 2018 Chapter 11 bankruptcy. The Z50/Z23/Z24/Z73 motor run cans, AeroMet plastic-case motor capacitors, PRS industrial film, 2779 high-voltage film, and PFC banks are all discontinued — but every common Aerovox part has a current equivalent from Cornell Dubilier (CDE), KEMET, TDK EPCOS, or Vishay. Match µF, VAC, and physical dimensions from the original can.
Aerovox: A Brief History
Aerovox Corporation was founded in 1922 in Brooklyn, New York as a maker of radio-frequency components, then later relocated to New Bedford, Massachusetts, where the company stayed for the rest of its independent existence. For nearly a century Aerovox was one of the largest American manufacturers of motor run capacitors, motor start capacitors, AC film capacitors, and power factor correction (PFC) banks.
Aerovox capacitors were ubiquitous in HVAC compressors, pool pumps, deep-well pumps, ceiling fans, garage-door openers, and industrial three-phase motor starters. Their Z-seriesoil-filled metal-can motor run capacitors became a de facto standard, with the case-style codes (Z50 = 1.25" round, Z23 = 1.75" round, Z24 = 2.0" round, Z62 = 2.0" oval) directly indicating the physical envelope. The AeroMet II plastic-case series filled the residential HVAC market from the 1990s onward; the PRS and 2779 heavy-duty film capacitors served industrial drives and lighting.
In 2018, after years of competitive pressure from offshore manufacturers and shifting demand, Aerovox filed for Chapter 11 bankruptcy and ceased independent operations. The brand and remaining tooling were transferred during the wind-down. Aerovox-branded capacitors are no longer produced new, but tens of millions of units remain in service in HVAC and industrial equipment — and the demand for replacements is steady. Specap maintains remaining Aerovox stock and provides specification-matched equivalents from current manufacturers.
Aerovox Motor Run Cross-Reference
Z50 / Z23 / Z24 / Z62 series motor run capacitors are the most-searched Aerovox parts. Match the µF rating and voltage class; physical envelope must fit the original chassis cutout (oval ≠ round). 440 VAC units can replace 370 VAC units of the same µF, but never the reverse.
| Original Part # | Type | Capacitance | Voltage | Modern Equivalent | Notes |
|---|---|---|---|---|---|
| Z50S3705M | Motor run, oval (1.25" base) | 5 µF | 370 VAC | CDE DERA135PB, generic 5 µF / 370 VAC oval | Fan motor, small HVAC |
| Z50S3707N | Motor run, oval (1.25") | 7.5 µF | 370 VAC | CDE DERA175PB, NTE MRC370V7P5 | Fan motor, blower |
| Z50S3710M | Motor run, oval (1.25") | 10 µF | 370 VAC | CDE DERA110PB, generic motor run | Small HVAC blower |
| Z23S3715M | Motor run, round (1.75") | 15 µF | 370 VAC | CDE DERA215PB, NTE MRC370V15 | Compressor or fan run cap |
| Z23S3720M | Motor run, round (1.75") | 20 µF | 370 VAC | CDE DERA220PB, generic 20 µF / 370 VAC | HVAC compressor |
| Z23S3725M | Motor run, round (1.75") | 25 µF | 370 VAC | CDE DERA225PB, NTE MRC370V25 | AC compressor |
| Z23S3730M | Motor run, round (1.75") | 30 µF | 370 VAC | CDE DERA230PB, generic motor run | Heat pump compressor |
| Z23S3735M | Motor run, round (1.75") | 35 µF | 370 VAC | CDE DERA235PB, NTE MRC370V35 | Compressor run cap |
| Z24S3740M | Motor run, round (2.0") | 40 µF | 370 VAC | CDE DERA240PB | Larger HVAC compressor |
| Z24S3745M | Motor run, round (2.0") | 45 µF | 370 VAC | CDE DERA245PB, generic 45 µF / 370 VAC | Compressor / dual-run pairing |
| Z24S3750M | Motor run, round (2.0") | 50 µF | 370 VAC | CDE DERA250PB, generic motor run | Large compressor run cap |
| Z23S4415M | Motor run, round (1.75") | 15 µF | 440 VAC | CDE DERA315PB, generic 15 µF / 440 VAC | 440 VAC service margin |
| Z23S4425M | Motor run, round (1.75") | 25 µF | 440 VAC | CDE DERA325PB, NTE MRC440V25 | Heat pump 440 VAC |
| Z23S4430M | Motor run, round (1.75") | 30 µF | 440 VAC | CDE DERA330PB | Compressor 440 VAC |
| Z73S4015MN | AC oil-filled, round (HID-style) | 15 µF | 400 VAC | CDE metal-halide capacitor, generic 15 µF / 400 VAC oil-filled | Metal-halide ballast 250 W |
| Z73S4024MN | AC oil-filled, round (HID-style) | 24 µF | 400 VAC | Generic 24 µF / 400 VAC HID lighting capacitor | Metal-halide ballast 400 W |
CDE DERA suffixes shown are representative — confirm exact part number against current CDE catalog when ordering. Generic motor run capacitors of the same µF, VAC, and physical envelope are also acceptable.
Aerovox Film, PFC & Electrolytic Cross-Reference
Industrial film capacitors and PFC banks. PRS and 2779 are the heavy-duty industrial workhorses; AGS/AGM PFC banks need careful selection on kVAR and voltage class. Power factor correction replacement should always be verified against the original installation drawings.
| Original Part # | Type | Capacitance | Voltage | Modern Equivalent | Notes |
|---|---|---|---|---|---|
| AeroMet II (M22P) | Plastic-case motor run | 5 – 80 µF (typical) | 240 / 370 / 440 VAC | CDE DERA, generic plastic-case motor run | AC condenser fan, residential HVAC |
| PRS / SC | AC motor run, metallized PP | 1 – 100 µF (typical) | 370 – 660 VAC | CDE DCMC, TDK EPCOS MKP, KEMET C44P | Industrial motor run |
| AGS / AGM | Power factor correction | Multi-kVAR | 240 – 600 VAC (typical) | TDK EPCOS PhaseCap, ABB CLMD, Vishay PhMKP | Industrial PFC banks |
| 2779 | AC capacitor, heavy duty | 0.1 – 100 µF (typical) | 600 – 4000 VAC | TDK EPCOS MKK, Vishay PhaseCap, CDE 942C | Pulse, snubber, AC filter |
| SXB / SXE | DC link film, high current | 10 – 1500 µF (typical) | 450 – 1300 VDC | TDK EPCOS DC link, CDE 947C, Vishay MKP | VFD DC bus, inverters |
| V Series | AC oil-filled film | 1 – 100 µF (typical) | 240 – 660 VAC | CDE 942C, Vishay MKP series | Industrial lighting ballasts |
| SA / Z62 | Motor start, electrolytic | 53 – 1080 µF | 110 / 165 / 250 VAC | CDE MSR, NTE motor start, generic motor start | Single-phase induction motor start |
| CGS (Aerovox) | Computer-grade screw terminal | 1500 – 33,000 µF (typical) | 10 – 450 V | CDE 381LR / 520C, Nichicon LGU / LQR | UPS / VFD DC bus |
| EAF | Photoflash / pulse electrolytic | 100 – 5000 µF (typical) | 300 – 500 V | CDE 947C (film alt), Nichicon photoflash, Vishay 116 | Strobe, pulse discharge |
How to Identify an Aerovox Capacitor
Aerovox motor run capacitors used a structured part-number system that decodes directly into case style, voltage, and capacitance. Once you know the format, the cross-reference is mostly automatic.
Z-series motor run part-number format: Z[case]S[volts][µF][impreg][term]
- Case code (first two digits):
50= 1.25" round,23= 1.75" round,24= 2.0" round,26= 2.5" round,42= 1.5" oval,62= 2.0" oval,64= 1.75" oval,73= round (HID lighting style). - S = SuperSoy® impregnant (modern soybean oil-based dielectric); older Aerovox used P = Supernol® (M series).
- Voltage code (next two digits):
24= 240 V,33= 330 V,37= 370 V,44= 440 V,48= 480 V,60= 600 V. - Capacitance (next two digits): literal µF value —
05= 5 µF,25= 25 µF,40= 40 µF. - Terminal code (M01 / N01 / W05): M = standard 4-blade quick-connect, W05 = wire leads, N = oval / no terminal variant.
Example: Z50S3707N01decodes as 1.25" round / SuperSoy / 370 VAC / 7.5 µF / oval-style terminal. The capacitance and voltage are stamped or printed directly on the can; UL ratings and life-hour spec (60,000 hr typical) are also visible.
AeroMet II plastic-case motor run capacitors use the part-number prefix M22P followed by voltage and µF in the same scheme. 2779 series film capacitors use a dedicated industrial part number with voltage / µF in plain text on the can.
What Replaced Aerovox?
Aerovox’s product mix is broad — motor run, motor start, PFC, industrial film, and electrolytic — and no single company absorbed all of it. Replacement vendors split by product family:
- Motor run (Z-series, AeroMet) — Cornell Dubilier (CDE) DERA / DCMC lines and KEMET C44P are the broad-line equivalents in the U.S. market. Mars, Packard, and other HVAC OEMs sell rebranded motor capacitors that are interchangeable as long as µF / VAC / case match.
- Motor start (Z62, SA) — CDE PSU, NTE motor-start lines, and any generic single-phase motor start capacitor of matching µF and VAC.
- Power factor correction (AGS, AGM) — TDK EPCOS PhaseCap, ABB CLMD Series, and Vishay PhMKP banks. PFC must be sized in kVAR and matched to the supply voltage class — direct part-for-part substitution is rare, so verify against the original installation drawings.
- High-voltage film (2779, SXB, SXE) — TDK EPCOS DC link, CDE 947C polypropylene DC link, Vishay MKP, and KEMET C44P high-voltage film series cover modern inverters and pulse applications.
- Computer-grade electrolytic (CGS Aerovox) — CDE 381LR / 520C and Nichicon LGU / LQR. (Aerovox CGS shares the CGS prefix with Mallory CGS — the cross-reference is the same family of CDE/Nichicon parts.)
- Photoflash / pulse (EAF) — CDE 947C (film alternative), Nichicon photoflash electrolytic series, or specialized pulse-rated capacitors from General Atomics for high-energy lasers and strobes.