If you're holding a GE Spectra RMS breaker that's failed, or you're maintaining a lineup full of them, you've probably found that the line is no longer current production. This GE Spectra to Tmax XT cross-reference gives you the frame-by-frame replacement chart, explains why matching the frame alone isn't a finished part number, and lays out the three practical ways to keep your gear running: a Tmax XT drop-in, an ABB retrofit kit, or a new-surplus Spectra original from stock. We stock and cross-reference circuit breakers in all four conditions, so whichever route fits your job, we can source it.
Why GE Spectra breakers are being phased out
When GE's Industrial Solutions business joined ABB, GE's low-voltage breaker lines moved under the ABB umbrella. The Spectra RMS molded-case family is now treated as a previous-generation product in a limited life-cycle phase, and ABB points new designs to its Tmax XT family instead.
For a plant engineer or maintenance team, the practical effect is simple: new Spectra breakers are getting harder to find and more expensive when you do find them. That's exactly why a reliable cross-reference matters. Rather than re-engineer or replace an entire panelboard, you can identify the correct Tmax XT equivalent, or keep the panel exactly as-is with a surplus or obsolete Spectra original.
GE Spectra to ABB Tmax XT cross-reference chart
Spectra RMS was built on four molded-case frames — SE, SF, SG, and SK. Tmax XT is built on seven — XT1 through XT7 — which gives you finer sizing granularity. That's why a single Spectra frame often maps to two XT frames: you pick between them based on your exact ampere rating and interrupting requirements. The frame-level mapping below follows ABB's published Spectra-to-Tmax XT transition guidance.
GE Spectra frame | Spectra ampere range | ABB Tmax XT replacement frame(s) | Notes |
SE | 15–150 A | XT1 / XT2 | Choose XT1 or XT2 by exact amp rating and interrupting class |
SF | 70–250 A | XT3 / XT4 | XT4 adds electronic (Ekip) trip-unit options |
SG | 60–600 A | XT5 | Direct frame-level match |
SK | 300–1200 A | XT6 + XT7 | Larger ratings split across two XT frames |
" A cross-reference is a starting point, not an approval. Physical fit does not equal code, UL, or AHJ acceptance. Always confirm the exact rating and installation against the equipment nameplate and your local Authority Having Jurisdiction before energizing. "
A frame match isn't a part number — confirm these five things
The chart above tells you which Tmax XT frame to look at. To turn a Spectra catalog number into the *correct* Tmax XT part number, you still need to match five details:
- Exact ampere rating. The frame sets the ceiling; you still specify the actual trip rating within it.
- Trip unit type. Spectra RMS units are electronic. Tmax XT gives you a choice of thermomagnetic (for example, TMD/TMA) or electronic Ekip trip units — so decide which behavior you're replicating.
- Interrupting rating (kAIC). Tmax XT frames come in several interrupting-performance classes (typically N, S, H, L, and V). Match or exceed the available fault current at your system voltage — never fall below it.
- Poles and voltage. Confirm 2-, 3-, or 4-pole and the system voltage.
- Mounting, connections, and accessories. Fixed vs. plug-in vs. drawout, lug type, and any shunt trips, auxiliary contacts, undervoltage releases, or handle mechanisms.
Miss any one of these and the breaker may physically fit but protect the circuit incorrectly. If you'd rather not chase all five, send us the Spectra catalog number and we'll return the exact ABB Tmax XT match.
Replacing a whole Spectra panelboard or switchboard?
You have three routes, depending on how much of the existing gear you want to keep:
- Drop-in breaker cross-reference. Swap individual Spectra breakers for their Tmax XT equivalents using the chart above plus the five checks. Best when a breaker (not the whole panel) has failed.
- ABB Tmax XT retrofit kit. ABB offers retrofit kits that install Tmax XT breakers into existing Spectra panel boards and switchboards without replacing the enclosure. Best when you're modernising a lineup but want to keep the structure and bus.
- Keep the panel as-is with an original Spectra. Source a new, new-surplus, or obsolete Spectra breaker so nothing about the installation changes. Best when downtime, documentation, or a fleet-of-identical-panels standard makes an exact original the easiest path.
We can cross-reference the Tmax XT part or supply the Spectra original from stock, so you're not forced into a full gear replacement to solve a single failed breaker.
How to read your Spectra catalogue number (30-second primer)
The frame is encoded at the front of the Spectra catalogue number — the SE, SF, SG, or SK prefix — and the characters that follow indicate the number of poles, the ampere rating, and the interrupting class. That prefix is all you need to enter the chart above. If the label is worn, painted over, or you're not certain, don't guess: send us a photo of the nameplate or the catalogue number and we'll identify it.
Get an exact cross-reference, same day
Have a GE Spectra breaker to replace? Send us the catalog number (or a nameplate photo) and we'll match the exact ABB Tmax XT part — or supply a new, new-surplus, or obsolete Spectra original from our inventory. Orders placed before 12 PM EST ship the same day. Browse circuit breakers in stock or send us your part number for a quote.
Frequently asked questions
Spectra RMS is a previous-generation line in a limited life-cycle phase under ABB, and its current replacement is the ABB Tmax XT family. Original Spectra breakers are still available through new-surplus and obsolete inventory, which is how many facilities keep existing panels unchanged.
The ABB Tmax XT family replaced it. Tmax XT spans seven frames (XT1–XT7) that cover the ampere ranges of the four original Spectra frames (SE, SF, SG, and SK).
The Spectra SG frame (60–600 A) cross-references to the ABB XT5 frame. Confirm the exact ampere rating, trip unit, and interrupting class before ordering.
Not as a loose drop-in in most cases. For existing Spectra panelboards and switchboards, ABB offers Tmax XT retrofit kits designed for that purpose. For anything else, match the frame, confirm the exact rating, and verify against the panel label and your local AHJ.
Start with the frame from the chart, then match the ampere rating, trip-unit type, interrupting rating, poles, voltage, and accessories. If you'd rather skip the lookup, send your Spectra catalog number to JW Electrical Supply and we'll return the exact match.