A Winch Solenoid Has Several Amp Ratings, Not One

Ask what amp rating a winch solenoid needs and you will be given a number. The number is almost always wrong, not because it is inaccurate but because these components do not have a rating. They have several, published side by side on the same datasheet, and the spread between them is large: Albright rates its SW200 at 250A thermal and 730A intermittent, and Cole Hersee rates one solenoid to close onto 750A while interrupting only 100A.

Once you can read the four, the question that sounds like a contradiction — how does a 65-amp part sit in a 400-amp circuit — stops being one.

Four Ratings on One Albright Datasheet

Open Albright’s datasheet for the SW200 contactor and you find, for one part:

• Thermal Current Rating (Ith) — 250A in one column, 400A in another
• Intermittent Current Rating at five duty cycles — 455A/730A at 30% duty, falling to 300A/480A at 70%
• Rated Fault Current Breaking Capacity — 1500A at 96V DC
• Auxiliary Thermal Current Rating — 5A, for the small auxiliary contacts, not the main path

The two columns are not sizes. Albright defines them on the sheet itself, and the definitions are about how often the part switches under load:

“Interrupted current - opening and closing on load with frequent switching (results in increased contact resistance).”

“Uninterrupted current - no or infrequent load switching requirements (maintains a lower contact resistance).”

So the lower column applies when the contactor repeatedly makes and breaks a live circuit; the higher one when it mostly just carries current. Same hardware, different job, different number.

The Ladder, From Albright’s Own Datasheets

Every figure below was read from the manufacturer’s PDF, and each URL was redirect-checked before citing.

Notice what the intermittent column does. On the SW200 the 30% duty figure is nearly double the thermal rating, and the uninterrupted 30% figure is almost three times it. A part described in a forum as “a 250-amp contactor” is also, accurately, a 730-amp contactor.

Make and Break Are Not the Same Rating

This is the number that actually resolves the question, and it comes from Cole Hersee’s catalog rather than Albright’s.

Cole Hersee rates its intermittent-duty solenoid family as “750A make, 100A break, 10sec On, 20min Off”. Its UL-listed 24059-08 carries the same asymmetry on one line: “Continuous Rating: 65A at 12V DC. Intermittent rating: 750A make, 100A break. 10 sec On, 30 min Off.” (The catalog’s Continuous Duty section defaults to “85A except where noted”; the 24059-08 is one of the noted exceptions, so 65 A is its figure, not 85.)

Read that again, because it is the whole answer. The part is rated to close onto 750 amps and rated to interrupt only 100. Making a circuit and breaking it are different electrical events, and breaking is far harder — the contacts have to stop a current that does not want to stop, and the arc that follows is what damages them.

A winch is exactly this shape of load: enormous current, closed briefly, ideally not interrupted at full load. That asymmetry is why a component’s headline number tells you so little on its own — and, as the next section shows, it still does not account for everything the part is asked to do.

What the Winch Actually Draws

None of the above means anything without the load. WARN’s 2025 Full Line Catalog publishes 12V DC Performance Specs as text, and for a 12,000 lb class winch they read:

Set that against the ladder, and be honest about what it does and does not explain. A DC88’s thermal rating is 100A and its 30%-duty intermittent rating is 185A. Both are well under 396A. Its fault-breaking capacity is 800A, but that is a UL583 fault rating measured at a 5ms time constant — an abnormal-event number, not operating headroom, and it should not be read as covering normal service.

The make and break ratings explain the switching moments, and the duty-cycle ratings explain why a brief pull is not a continuous load. Neither covers the middle of the pull, when the part is simply carrying several hundred amps.

There is a rating class for exactly that, and Trombetta publishes it. Its PowerSeal “Full Silver” Intermittent Duty sheet lists “Inductive Load Carry/ Interrupt (Amps) 310/300” on its 12 V and 24 V coils (310/225 at 36 V and 48 V), alongside “Max Sustained Duty Cycle 25%”, “Max On-Time 6 min” and “Peak Inductive In-Rush Capability (Amps) 1,000” at 12 V and 24 V. Carry and interrupt are rated separately there too, and the sheet bounds how long the part may stay closed at all.

That is the number to compare against a winch, and it is worth seeing where it lands: 310 A carry against 396 A at a 12,000 lb winch’s rated pull. The rating class exists and is published; it simply is not comfortably above the load on the largest winches, which is a reason to match a specific part to a specific winch rather than trust a headline figure.

The awkward part is structural. Winch makers publish motor current without component duty ratings; component makers publish duty ratings without naming a winch. Both halves exist, in different documents, from different companies — and no source found for this page brings them together for a named winch and a named part.

Our winch amp draw guide has the full manufacturer-sourced current tables if you want the numbers for your own winch.

Which Is Why They Weld

The failure mode follows directly from the ratings. If the low number is the break rating, then breaking under load is the thing that kills these parts.

Omron, describing relay contacts in general, gives the mechanism: “Arcing happens when the relay opens or closes, especially if there’s an inductive load (like a motor or solenoid)… This arc can heat the contacts to the point of melting or welding.” And separately, that contacts exposed to “a current above their rated capacity… may heat up and soften, which can lead to the contacts fusing or welding together.”

A winch motor is that inductive load, and releasing the switch mid-pull is that interruption. When the contacts weld, the winch does not stop — which is a genuinely dangerous situation covered on our page for a winch that won’t stop running.

Albright’s higher-end parts address this directly with magnetic blowouts, which its glossary describes as “used to assist breaking of arcs associated with high voltage. Recommended for applications of 48v (inductive) / 60v (resistive) and over.” On a 12V winch that threshold is not reached, so the blowout option is aimed at duty a winch does not present. It is not absent from these parts, though: Albright lists magnetic blowouts as standard on the SW200 and as an option (the B suffix) on the SW60, SW80, SW180 and DC88.

Is a Contactor Really Different From a Solenoid?

Technically yes. In practice the winch industry does not apply the distinction consistently, and it is worth knowing both facts before reading any product listing.

The component makers are clear. Albright’s glossary defines the solenoid as the actuator: “the solenoid (coil) is energised to generate the electro magnetic force for moving the armature.” Albright then names every one of its own switching products a contactor — “DC88P monoblock D.C. contactor for motor reversing.” Trombetta defines a DC contactor as “an electrical switching device that has the ability to handle high current levels,” and separately describes industrial solenoids as “devices that are distinguished by a push or pull motion from point A to point B and often used in general locking and latching applications.”

The winch brands split. WARN names the part a contactor in its own parts listing: its replacement unit for the M12 and M15 is titled a contactor, and the word solenoid does not appear on that page at all. Superwinch’s replacement-parts catalog carries “Contactor” and “Solenoid” as distinct product categories. But Ramsey, Smittybilt and Badland use only the word “solenoid” throughout their own manuals, for parts that by the component makers’ definition are complete contactors.

There is no amperage threshold that divides the terms. Sources claiming one exist, and they disagree with each other — 15A, 20A and 25A all appear as the supposed cutoff, none from a manufacturer datasheet or a standards body. The real dividing line in the datasheets is duty rating and arc handling, not a number.

Cole Hersee, for its part, names the application directly: its catalog says solenoids “are commonly used to control starter and winch motors,” and specifies its reversing solenoids “for forward and reverse systems in electric golf carts, garden tractors, fork lift trucks, winches, etc.”

What the Popular Comparison Gets Wrong

Search this question and three of the top results give you near-identical wording: a solenoid switching “heavier current that varies from 80 to 200-amps” against a contactor at “100 to 600-amps.” None of the three cites a manufacturer datasheet.

The ranges are not simply imprecise. They are unreadable, because no rating class is attached. Real datasheet figures for these parts run roughly 65A to 400A thermal and 95A to 730A intermittent depending on part and duty cycle, with make and break ratings sitting on top of both. “80 to 200 amps” could describe a thermal rating, an intermittent rating at some unstated duty, or a break rating, and those describe three different components’ worth of capability.

What Winch Makers Publish, and What They Don’t

Across the OEM literature checked for this page — WARN, Superwinch, Ramsey and Smittybilt — none publishes a continuous or intermittent duty rating for its own solenoid or contactor in the form the component manufacturers use. What these makers do publish well is motor current draw, which is the other half of the calculation.

That is the practical gap: to compare a replacement part against your winch properly you need a rating class from the component maker and a current figure from the winch maker, and they are published in different documents by different companies. Anyone quoting you a single number for both is not comparing like with like.

How We Chose

Every figure on this page was read from the manufacturer’s own datasheet or catalog, and every URL was redirect-checked with curl before it was cited, so that one document served under two addresses is never counted as two sources. Where a rating is quoted, the rating class is stated with it — thermal, intermittent at a named duty cycle, make, break, or fault breaking — because these components publish several and a bare amp figure is not checkable. Where a claim is about what manufacturers do not publish, it is scoped to the specific documents checked rather than stated about the industry. Full sourcing and rating methodology: review methodology.