Schneider EasyPact CVS vs ComPact NSX: Differences Explained

What separates Schneider's EasyPact CVS from the ComPact NSX? Both are IEC 60947-2 molded case circuit breakers built across the same 15-630 A current range and similar frame logic, but EasyPact CVS is Schneider's economy tier — thermal-magnetic trip units, breaking classes capped in the B/F/N band — while ComPact NSX is the upper tier, extending through H, S, and L classes toward 150 kA at 415 V and offering field-swappable Micrologic electronic trips with metering and communication. Picking the wrong tier means either paying for LSIG protection and Modbus a feeder will never use, or under-protecting a circuit that needed selective coordination. This article compares frame and current overlap, breaking-capacity classes, trip-unit options, metering and communication capability, accessory catalogs, and the project types where EasyPact CVS is the sound engineering choice instead of ComPact NSX.

Frame and Current Range: Where CVS and NSX Overlap

EasyPact CVS covers 15 A to 630 A across four frame sizes (CVS100, CVS160, CVS250, CVS400/630), which mirrors the low end of the molded case circuit breaker current span Schneider offers on ComPact NSX100/160/250 and NSX400/630. On paper the ampere ratings line up almost exactly. The difference is not what current the breaker carries continuously — it is what happens during a fault, and how much information the breaker gives you afterward.

That overlap is intentional. Schneider designed CVS as a lower-cost path into the same physical footprint family, so panel builders standardized on NSX enclosures and mounting can drop in a CVS breaker without redesigning the panel. Where they diverge is internal: breaking capacity, trip technology, and everything downstream of the trip unit.

Breaking Capacity Classes: CVS Tops Out Where NSX Begins to Stretch

Schneider's MCCB breaking-capacity ladder runs B(25), F(36), N(50), H(70), S(100), L(150) kA at 415 V. EasyPact CVS is offered through the lower rungs of that ladder — B, F, and N class, topping out around 50 kA on its largest frames. ComPact NSX carries the same ladder further: H, S, and even L class on selected NSX630 frames, reaching toward 150 kA at 415 V. For a full breakdown of what each letter means, see our guide on MCCB breaking capacity ratings.

On some Schneider NSX classes, Ics is rated at 50-75% of Icu rather than 100%. Size around Ics, not the headline Icu number on the nameplate — a breaker that survives one fault at its ultimate rating but can't be trusted afterward is not doing the job a feeder protection device is supposed to do.

Run that check before you pick a tier. If the calculated prospective fault current at the board is comfortably inside N-class territory (50 kA), EasyPact CVS covers it. If a utility upgrade or transformer resize pushes fault current into H or S territory, only ComPact NSX has the headroom.

Trip Units: Thermal-Magnetic Only vs Field-Swappable Micrologic

EasyPact CVS ships with fixed thermal-magnetic TM-D trip units as standard, with an electronic option available only on the largest CVS400/630 frames. Even there, the electronic option is a basic long-time/short-time (LSI) function, not the full LSIG family. ComPact NSX trip units are field-swappable modules across the whole range: TM-D/TM-G thermal-magnetic on the smaller frames, and Micrologic electronic units on the rest — 2 (LI, long-time + instantaneous), 5 (LSI), 6 (LSIG, adds earth-fault protection), 7 (adds earth-leakage).

Fewer trip options on CVS is not a shortfall — it is the point of the economy tier. A distribution board feeding fixed lighting or HVAC loads rarely needs adjustable ground-fault protection or a swappable trip module years down the line. What we see in the field: panel builders standardize on CVS with TM-D for exactly this reason, then reach for NSX only when a spec calls for selective coordination studies or LSIG discrimination between upstream and downstream devices.

Metering and Communication: The Real Dividing Line

This is where the two lines diverge most for a spec writer. ComPact NSX Micrologic units are available in "E" variants — 5E, 6E, 7E — that add true RMS power and energy metering (kW, kWh, power factor, THD) directly on the trip unit display, plus an optional IFM or COM communication module for Modbus RTU integration into a building management or SCADA system. EasyPact CVS has no equivalent metering-and-comms path; it protects the circuit and nothing else.

This single capability gap accounts for a large share of the price difference between the two lines. Paying for it on a feeder that will never be monitored is money spent for no engineering reason; paying for it on a tenant-metered or energy-audited panel is the reason the ComPact NSX exists.

Accessories: What NSX Offers That CVS Doesn't

Common accessories are available on both lines: shunt trip (MX) release, undervoltage release (MN), auxiliary and alarm contacts, rotary handles. Basic remote tripping and status signaling work regardless of tier. Where NSX pulls ahead is motorized operation and communication hardware — motor operators (MO) for remote racking/reclosing, and the IFM/COM Modbus modules mentioned above. CVS's accessory catalog is intentionally narrower. It covers the signaling and interlocking that a standard distribution panel needs, not remote motorized operation.

Frame and current ratings, covered further in our guide to MCCB voltage, current, and frame sizing, stay consistent across accessory choice — an accessory decision doesn't change which frame size you need, only what the breaker can do once it's mounted.

Comparing the Two Lines Side by Side

When EasyPact CVS Is the Right Call

Not every panel needs ComPact NSX. EasyPact CVS is the correct — not merely cheaper — choice when three conditions hold: prospective fault current at the board stays within N-class (50 kA) territory, the circuit doesn't need LSIG discrimination against upstream or downstream devices, and nobody has specified circuit-level metering or Modbus visibility. That covers a large share of general distribution boards, lighting and small-motor feeders, and secondary panels in industrial and commercial buildings.

Where it isn't the right call: main incomers on panels with high available fault current, feeders that must selectively coordinate through a documented time-current study, and any circuit named in a tenant submetering or energy-management spec. Our MCCB selection checklist walks through these conditions in more detail if you're sizing a mixed panel with both breaker tiers in it.

This depends on duty cycle and how conservative the fault-current calculation was at design time, admittedly — a panel with margin baked in at N-class might run for the life of the installation without ever approaching CVS's ceiling. Some engineers argue for specifying NSX everywhere as a hedge against future upstream changes, but in practice that adds cost across every feeder for a risk that sits almost entirely at the incomer, not the branch circuits. For the broader category context, see our overview of molded case circuit breaker types and the full MCCB engineering guide.

Conclusion

EasyPact CVS and ComPact NSX share a current range and a family resemblance, but they are not interchangeable once fault current, trip-unit flexibility, or metering enters the spec. CVS covers B/F/N breaking classes with fixed thermal-magnetic trips and no metering or communication path — it is the right breaker for standard distribution feeders within its fault-current ceiling. ComPact NSX extends through H, S, and L class, accepts field-swappable Micrologic trips up to LSIG plus energy metering, and supports Modbus communication and motorized operation. Size around Ics against the calculated prospective fault current, decide whether the circuit needs LSIG discrimination or metering, and only then pick the tier — not the other way around.