Specifying a motor for a Class I, Division 1 area, the spec sheet is only half the battle. The motor has to contain an internal ignition without becoming the ignition source for the room around it — and still hit the horsepower, speed, and frame you actually need. Too often the catalog forces a tradeoff: the right hazardous-location rating, but only at a fixed speed, only in a frame that won't drop into your footprint, or without the inverter rating you need to run it on a drive.
At HESCO, we help customers spec motors for exactly these environments, where the cost of getting the rating wrong isn't downtime, it's a safety incident. WorldWide Electric's IXPEWWE series covers the common hazardous-location requirements without the usual gaps in the lineup. Here's what it covers, what the ratings mean, and where it fits.
| Spec | Rating |
|---|---|
| Type | Three-phase TEXP (Totally Enclosed Fan Cooled, Explosion Proof) |
| Power range | 1–250 hp |
| Speeds | 3600 / 1800 / 1200 rpm |
| Frames | NEMA 143–447/9 (T, TS, TC) |
| Voltage | 230/460V (1–100 hp); 460V (125–250 hp) |
| Hazardous rating | UL Listed — Class I Div 1 Groups C & D; Class II Div 1 Groups F & G |
| Inverter duty | Standard — 5:1 constant torque / 10:1 variable torque |
| Efficiency | Premium efficiency, full range |
| Insulation / protection | Class F / IP55 |
| Service factor | 1.15 |
| Mounting | Rigid base (foot) and C-face with feet |
| Thermal protection | Normally-closed winding thermostats, standard |
The short version: an explosion proof motor line that doesn't make you compromise on speed, frame, or inverter rating to get the Class I/II Division 1 listing.
An explosion proof motor isn't sealed against an explosion getting in — it's built to contain one that happens inside it. If flammable gas or dust migrates in and ignites, the enclosure withstands the internal pressure and cools the escaping gases enough that they don't ignite the surrounding atmosphere. That's a different design and certification path than a standard TEFC motor, which is why these ratings are specific and non-negotiable.
The IXPEWWE's coverage spans both gas and dust:
That combination covers the bulk of petrochemical, oil and gas, and grain handling applications from a single series, instead of forcing separate motors for gas and dust environments.
The value of an explosion proof line is how completely it covers the combinations engineers actually request — 1–250 hp, three speeds, NEMA 143 through 447/9, in both foot-mount and C-face. A C-face motor on a close-coupled load isn't interchangeable with a foot-mount, so having both in one series means you're not jumping to a different product line — and a different rating sheet — to match the mechanical interface.
Two things worth knowing:
IXPEWWE7.5-36-213T = family, hp (7.5), rpm ÷ 100 (36 = 3600), frame (213T). Faster to cross-reference against a nameplate or BOM.Every rating is inverter duty rated (5:1 constant torque / 10:1 variable torque) and premium efficiency across the full range. The inverter rating is the one that saves you a headache: explosion proof motors frequently run on VFDs for pump and fan control, and a motor that isn't inverter-rated can see premature insulation and bearing failure from drive voltage spikes — which, in a hazardous location, is a safety question, not just a maintenance one.
The T-code is the maximum surface temperature the motor reaches, and it has to stay below the autoignition temperature of whatever's in your atmosphere. On the IXPEWWE it varies by frame size — read it carefully:
| Configuration | Temp code | Max ambient |
|---|---|---|
| Standard | T3C | 40°C |
| Frames 143T–215T | T3C | 55°C |
| Frames 254T–449T | T2C | 55°C |
T3C is a tighter (lower) max surface temperature than T2C — so the smaller frames give you the more conservative rating, while the larger frames allow a higher surface temperature at the same elevated ambient. If your hazardous material has a low autoignition point, that difference can decide whether a given motor is legal for your area. Confirm the T-code against your area classification, not just the Class and Division.
One more protection detail worth the callout: normally-closed winding thermostats are standard. Wired into your control circuit, they trip on a thermal fault before the motor cooks itself — a layer of protection you'd otherwise spec as an add-on, and one that matters more where surface temperature is part of the safety case.
The Class/Group coverage points to clear homes:
If you're running motors on drives in any of those settings — and most modern process lines are — the standard inverter rating means you're not hunting for a special. The series also ships from WorldWide's regional distribution network, which is the other half of the equation when an explosion proof motor goes down and the line is waiting.
If you're specifying for a hazardous location or cross-referencing an existing explosion proof motor for replacement, the IXPEWWE belongs on the short list. The HESCO team can help you match horsepower, speed, frame, mounting, and — most importantly — temperature code to your area classification, and confirm the configuration is available before you build it into a layout. Reach out and let's work through it together.