Canonical page for round electromagnet
120 volt round electromagnet guide with 12V proxy fit checks
For a 12 volt round electromagnet or a 120 volt round electromagnet, compare usable hold after gap, surface, direction, duty, and safety-margin losses. Run the checker, then confirm voltage-specific performance with the supplier.
Tool-first fit check
12V / 120V round electromagnet checker
Start with the real fit question users ask under both 12 V and 120 V alias phrasing: what remains after air gap, contact condition, load direction, and safety factor are applied? For 120 V inputs, the checker marks boundary status and routes you to voltage-class proof.
Result and next action
Working load and family recommendation
The checker estimates a conservative working load, then tells you whether to stay with a round holding magnet or change families entirely.
Empty state
Start with the real job, not the catalog headline.
Default inputs are set to an 11.5 lb, 12 V, small round electromagnet class. Run the checker to see how quickly usable load shrinks once air gap, surface quality, direction, and safety margin are applied. If your RFQ says 120 V, keep the result in boundary mode until the supplier confirms whether the model is 120 VAC or 110 VDC.
Public 12 V small-class reference
11.5 lb
Eclipse 20 mm M52180 at zero air gap
Same class at 0.09 mm gap
4.6 lb
Before any safety factor is applied
12 / 120 volt round electromagnet checkerCan 12V or 120V round magnets hold headline force?120V alias split: AC vs DC120V power window and compliance gateRound electromagnet family comparison12V round air-gap loss dataHow published evidence informs selectionRisk limits and failure modesRound electromagnet FAQ
12 volt dc electromagnet guide12v lifting electromagnet selection pageac electromagnet boundary guide12 volt linear solenoid checker12v electromagnetic clutch checkercustom electromagnet engineering path
This is the canonical route for 12 volt and 120 volt round electromagnet intent, so both aliases share one fit-checking and selection path.
Published April 11, 2026Research reviewed October 11, 2026Next scheduled review April 2027
This guide links fourteen reviewed public sources, including Eclipse (January 2025 v2), Kendrion technical notes, Schmalz operating instructions (09/2020), Kanetec lifting-magnet catalog data, 120 VAC / 110 VDC round-magnet product pages, OSHA 1910.179, ASME B30.20/BTH-1 scope pages, and USDA guidance citing ANSI C84.1 service-voltage ranges. Catalog ratings and force curves are supplier-published values; this page does not present independent physical test results.
Small 12 V reference
11.5 lb at zero gap
First real penalty
4.6 lb at 0.09 mm
Shear warning
20-33% of hold force
Quick Answer
Can a 12 volt or 120 volt round electromagnet hold headline force?
Short answer: treat headline force as a best-case steel-face result, not a safe working load. The 12 V public curve gives a usable baseline, and the 120 V alias is handled through explicit AC/DC branch logic on this same canonical URL.
Key number
114-126 V
120V service is a range, not a fixed point
USDA guidance citing ANSI C84.1-2016 shows 120 V service is a window under normal Range A conditions. Validate hold and release behavior at voltage edges, not just at nominal 120 V.
Key number
120VAC / 110VDC
120V requests split into two voltage classes
Industrial Magnetics publishes round electromagnets in both 120 VAC and 110 VDC classes. Magnetool’s 120 VAC notes add release and residual-force boundaries that do not appear in simple 12 V headline checks.
Key number
5.2 kg / 11.5 lb
11.5 lb is the catalog headline, not the working load
The closest public small 12 V example reviewed here is Eclipse M52180/12VDC: 20 mm diameter, 100% ED, 210 mA, and 5.2 kg holding force at zero air gap.
Key number
-60% at 0.09 mm
A 0.09 mm gap cuts the same class to 4.6 lb
That same Eclipse magnet drops from 5.2 kg to 2.1 kg at just 0.09 mm gap before any safety factor is applied.
Key number
20-33%
Sliding loads behave like a quarter-force problem
Kendrion publishes shifting force at only about 20-33% of holding force, so any sideways slip risk destroys the headline number quickly.
Key number
20-40%
Residual force can remain after power-off
Kendrion technical notes state residual holding force after deactivation can be around 20-40% depending on the workpiece, so release behavior must be validated.
Decision answers for round-electromagnet buyers
These answers are phrased to directly cover the round electromagnet intent cluster, including 12 volt and 120 volt alias phrasing.
| Question | Short answer | Why it matters |
|---|---|---|
| What is a 12 volt round electromagnet? | In public catalog terms it is a small energise-to-hold magnet class, not a certified lifting magnet. The closest reviewed example is a 20 mm 12 V part rated at 5.2 kg / 11.5 lb under zero-gap test conditions. | The phrase sounds like a lifting device, but the published product class is really about static holding force on a steel coupon. |
| What does “120 volt round electromagnet” usually imply? | Usually a mains-powered branch (120 VAC round models or 110 VDC round models), not the same evidence baseline as the 12 V small-magnet proxy. | If 12 V, 110 VDC, and 120 VAC are treated as interchangeable labels, release behavior and coil-selection decisions become unreliable. |
| What voltage window should a 120V branch be checked against? | For 60 Hz systems, USDA guidance citing ANSI C84.1 shows Range A service at 114-126 V, with wider Range B tolerated only for limited duration. | If validation happens only at nominal 120 V, low-line or high-line behavior can still fail during production. |
| Can it safely lift 11 lb in the real world? | Usually no. The same 20 mm class falls to 2.1 kg / 4.6 lb at 0.09 mm gap before any safety factor or surface derating is applied. | Paint, plating, rust, and poor flatness create exactly the kind of gap that makes field performance disappoint. |
| Does 12 V automatically mean continuous safe hold? | No. Voltage tells you the electrical class; it does not choose the right magnet family for long hold-open duty, power-fail-safe holding, or lifting. | You still need to decide between electro holding, permanent electro, door magnets, or purpose-built lifting magnets. |
| What if the load can slide sideways? | Treat that as a different problem. Kendrion publishes shifting force at only about 20-33% of the holding-force value. | A magnet that looks adequate on pull-off can still lose the part in shear without a mechanical stop. |
| When should I reject the small holding-magnet idea entirely? | Reject it for overhead lifting, pick-and-place WLL work, power-fail-safe retention, or door hold-open projects. | Those use cases point to different product families with different published proof and safety logic. |
| When does this become a compliance-gated lifting decision? | As soon as the use case is below-the-hook or overhead lifting, force screening alone is not enough. | OSHA 1910.179 and ASME B30.20/BTH-1 introduce control-circuit, marking, inspection, and testing requirements. |
| Can “power off” still leave the part stuck briefly? | Yes. Kendrion technical guidance says residual force after deactivation can remain at roughly 20-40% depending on the workpiece. | If your process needs clean, fast release, add a release check instead of assuming force goes to zero immediately. |
Good fit for this page
Fixture designers, automation engineers, and buyers comparing small 12 V hold magnets on clean ferromagnetic parts.
Bad fit for this page
Anyone who really needs a power-fail-safe latch, fire-door hardware, certified pick-and-place WLL, or overhead lifting approval.
Voltage-Class Split
How this page handles the 120 volt round electromagnet alias
The alias is merged into this canonical URL, but the decision path still branches by coil class. This table prevents AC/DC voltage terms from being mistaken for one interchangeable dataset.
Decision visual
One keyword, three voltage branches
The user intent is still round-electromagnet fit, so the URL stays canonical. What changes is the evidence branch: 12 V proxy screening, 120 VAC release-risk branch, or 110 VDC higher-voltage branch.
Alias voltage-class interpretation table
Known and unknown boundaries are both made explicit to avoid overconfident reuse of 12 V numbers.
| Search phrasing | Published signal | What it usually means | Boundary before RFQ |
|---|---|---|---|
| 12 volt round electromagnet | Eclipse M52180/12VDC publishes 5.2 kg (11.5 lb) zero-gap holding force with a 12 V, 210 mA, 100% ED reference. Source: Eclipse Magnetics M52xxx datasheet (January 2025 v2) | Compact DC energise-to-hold screening with strong dependence on gap and contact quality. | Use 12 V curve logic for first-pass screening, then verify on the exact steel face and duty cycle. |
| 120 volt round electromagnet (AC branch) | Industrial Magnetics publishes 120 VAC round models. Magnetool states its 120 VAC line is internally rectified to 110 VDC, can retain up to 20% residual magnetism without release pulse, and does not support electronic release via the built-in rectifier path. Source: Industrial Magnetics: round electromagnets (24VDC, 110VDC, 120VAC); Magnetool: 120 V.A.C. electromagnets (updated Nov 2025); USDA RUS Bulletin 1724D-114 (Dec 2017, cites ANSI C84.1-2016) | Facility-power holding branch where supply-voltage window and release behavior must both be verified. | Confirm 120 VAC coil class, clean-release method, and low/high-line behavior (normal service window 114-126 V) before approval. |
| 120 volt round electromagnet (DC branch) | Industrial Magnetics lists 110 VDC round options. Magnetool round lifting models also list 110 VDC variants with published lifting capacities and explicit 2:1 safety-factor ratings. Source: Industrial Magnetics: round electromagnets (24VDC, 110VDC, 120VAC); Magnetool: round lifting magnets (110 VDC, 2:1 safety-factor ratings) | Higher-voltage DC holding or lifting path, typically outside compact 12 V proxy assumptions. | Request voltage-specific pull/lift basis, duty rating, and safety-factor method before RFQ. |
Power + Compliance
120V supply window and lifting-compliance gate
A 120 V request needs separate supply-window checks and a different approval path when the application involves overhead lifting.
Power boundary visual
Nominal 120 V is a range decision
A 120 V keyword does not lock operation to one exact electrical condition. Treat low-line and high-line service behavior as separate checks, especially when release timing is safety-critical.
120V service-window boundary table
Compare expected low-line and high-line operation with the exact model data; nominal voltage alone does not confirm holding or release performance.
| Operating basis | Published window or constraint | Decision action |
|---|---|---|
| ANSI C84.1 Range A (60 Hz, 120 V class) | Service: 114-126 V; utilization: 108-127 V. Source: USDA RUS Bulletin 1724D-114 (Dec 2017, cites ANSI C84.1-2016) | Validate holding and release behavior at low-line and high-line conditions, not only at nominal 120 V bench tests. |
| ANSI C84.1 Range B (tolerable, limited duration) | Service: 110-127 V; utilization: 104-127 V. Source: USDA RUS Bulletin 1724D-114 (Dec 2017, cites ANSI C84.1-2016) | Range B is a temporary tolerance zone. Treat sustained operation there as a boundary case requiring thermal and release checks. |
| 120 VAC internal-rectifier branch | Magnetool states 120 VAC input is internally rectified to 110 VDC; up to 20% residual magnetism can remain without release pulse. Source: Magnetool: 120 V.A.C. electromagnets (updated Nov 2025) | Do not assume clean electronic release on every power-off event. Verify release method and de-energized behavior on the production part. |
Compliance gate when the job becomes lifting
This table defines when to stop force-only screening and switch to a documented compliance workflow.
| Trigger | Published requirement | Required action |
|---|---|---|
| Use case shifts to below-the-hook or overhead lifting | ASME B30.20 governs marking, construction, installation, inspection, testing, maintenance, and operation; ASME BTH-1 provides minimum structural/mechanical/electrical design criteria. Source: ASME B30.20 (2025): below-the-hook lifting devices; ASME BTH-1 (2023): design of below-the-hook lifting devices | Exit force-only screening and move into a lifting-device compliance workflow before approval. |
| Crane-mounted lifting magnet control circuit | OSHA 1910.179(g)(5)(iii)-(iv): provide a lockable means to open the magnet circuit and a means to dissipate inductive load. Source: OSHA 29 CFR 1910.179 overhead and gantry cranes | Review control architecture and release path in drawings before procurement. |
| Commissioning new or altered lifting installation | OSHA 1910.179(k)(2) caps rated-load test loads at 125% unless the manufacturer recommends otherwise; test reports must be kept readily available. Source: OSHA 29 CFR 1910.179 overhead and gantry cranes | Have the responsible crane professional determine the applicable test load and document the results; 125% is a maximum, not a minimum. |
| Electrical exposure to dirt, oil, or moisture | OSHA 1910.179(g)(2)(ii): crane electrical equipment shall be protected from dirt, grease, oil, and moisture. Source: OSHA 29 CFR 1910.179 overhead and gantry cranes | Confirm enclosure/wiring protection for the operating environment before sign-off. |
Family Guide
Choose the family before you argue over the force number
Most selection errors come from treating every magnet that can stick to steel as the same product category. The published evidence says otherwise.
Decision map
Four magnets, four different proof models
Stay with a plain electro holding magnet only when the job is static holding on a known steel face and the release on power loss is acceptable. Move families as soon as you need fail safe behavior, door hardware logic, or a real lift rating.
Product-family comparison
Published examples from Kendrion, Schmalz, Eclipse, and Kanetec.
| Family | Best for | Published signals | Not for |
|---|---|---|---|
| Electro holding magnet | Static clamping or holding on clean steel faces | Kendrion publishes 36-30,000 N, 12/24 V, and 100% ED. Source: Kendrion: electro holding magnets | Power-fail-safe hold, overhead lifting, or dynamic pick-and-place. |
| Permanent electro holding magnet | Low-energy hold or safe hold during power failure | Kendrion publishes currentless holding force, safe holding during power failure, and 8-3,500 N force range. Source: Kendrion: permanent electro holding magnets | Generic plug-and-play swaps where release pulse design is unknown. |
| Door holding magnet | Door hold-open systems and release hardware | Kendrion publishes 24 V DC, 300-1,568 N, and EN1155 / EN14637 context. Source: Kendrion: door holding magnets | Part clamping or steel-pick applications. |
| Magnetic gripper or lifter family | Pick-and-place or applications needing a 3:1 WLL mindset | Schmalz designs around a 3 safety factor, and Eclipse points pick-and-place toward dedicated families. Source: Schmalz magnetic gripper operating instructions (09/2020) | The cheapest small round magnet swap-in. |
| Purpose-built lifting magnet | Real lifted-load applications | Kanetec publishes separate lift capacity and says lift is half of holding power. Source: Kanetec catalog 098: lifting electromagnets | Assuming a small 11 lb hold magnet is “close enough” to a lifting system. |
Air-Gap Data
The 11 lb class answer changes fast once a real gap appears
This section is the 12 V baseline evidence layer. For 120 V alias intent, use this as directional logic only and branch to the voltage-class table before supplier decisions.
Encoded SVG chart
20 mm, 12 V hold curve proxy
The public 20 mm curve is useful because it is already in the same order of magnitude as the 11 lb search phrasing. It shows why a “small air gap” is not a small penalty on a small round holding magnet.
Eclipse 20 mm 12 V published air-gap points
All values below come from the reviewed Eclipse small-magnet datasheet. Units are shown in both kilograms and pounds for easier buying decisions.
| Air gap (mm) | Hold (kg) | Hold (lb) | Relative to zero gap |
|---|---|---|---|
| 0.00 | 5.20 | 11.46 | 100% |
| 0.09 | 2.10 | 4.63 | 40% |
| 0.18 | 0.90 | 1.98 | 17% |
| 0.27 | 0.45 | 0.99 | 9% |
| 0.36 | 0.30 | 0.66 | 6% |
| 0.59 | 0.20 | 0.44 | 4% |
| 1.00 | 0.10 | 0.22 | 2% |
Context note: this is a specific public 20 mm / 12 V magnet. Use it as a small-class proxy, not as a substitute for the exact supplier curve of your selected part number.
Method
How the checker turns a headline force into a usable decision
The checker does not pretend to know your hidden supplier data. It intentionally uses public facts where they exist, then makes its own assumptions visible instead of hiding them.
Flow
Catalog force to family choice
The sequence is simple: start with the catalog holding force, apply gap loss, apply real-contact and direction derating, divide by a safety factor, then ask if the use case actually belongs to another family.
What is public, and what still needs supplier proof
This is where the report layer earns trust instead of just repeating the tool result.
| Stage | Public evidence used here | Still unknown until you test or ask |
|---|---|---|
| 1. Start with published holding force | Use the supplier’s normal holding-force value, not the weight you hope to lift. | Whether that value came from a polished coupon or the real production part. |
| 2. Apply air-gap loss | The 20 mm Eclipse 12 V curve falls from 5.2 kg at zero gap to 2.1 kg at 0.09 mm. | Your exact part geometry and whether your magnet face behaves better or worse than the proxy. |
| 3. Apply contact and direction loss | Kendrion publishes shifting force at only about 20-33% of holding force. | The real steel chemistry, roughness, plating, and alignment in your assembly. |
| 4. Apply material and residual-force boundaries | Kendrion states force references are tied to material context (such as S235JR) and residual force can remain about 20-40% after deactivation. | Release performance on your exact steel grade, especially if hardened/alloy or if fast release is required. |
| 5. Apply safety margin and family screen | Schmalz uses a 3 safety factor for magnetic gripper design, and Kanetec publishes lift capacity separately from maximum holding power. | Whether the consequence of a dropped part demands a higher margin or a different family entirely. |
| 6. Trigger compliance workflow when lifting scope appears | OSHA 1910.179 and ASME B30.20/BTH-1 define control, testing, and design gates for below-the-hook lifting systems. | Whether your exact installation is classified as overhead lifting and which jurisdictional requirements apply to commissioning records. |
Selection evidence
Evidence gaps that change the magnet decision
See which published specifications help resolve common selection gaps, how each one changes the next step, and what still needs confirmation on your part.
Evidence that changes the decision
Reviewed October 11, 2026. Manufacturer data and standards are linked here; model-specific performance still needs confirmation.
| Decision question | What the source establishes | Next step | Source |
|---|---|---|---|
| What does an 11 lb, 12 V catalog rating describe? | Eclipse M52180/12VDC lists 5.2 kg at zero gap, 210 mA, about 2.4-2.5 W, and 100% ED in its January 2025 v2 datasheet. | Treat it as a catalog reference; validate force on the real workpiece and gap before approving a load. | Eclipse Magnetics M52xxx datasheet (January 2025 v2) |
| Will the same rating hold across different steel and temperatures? | Kendrion explains that material permeability, workpiece thickness, surface condition, and air gap affect holding force; the cited normal ambient context is -5 to 40 °C. | Provide the steel grade and operating temperature, then request model-specific force data if they differ from the published conditions. | Kendrion: technical explanations PDF |
| Does switching the magnet off guarantee immediate release? | Kendrion reports residual holding force of about 20-40% after deactivation, depending on the workpiece. | Measure release time and residual force on the production workpiece if release timing matters. | Kendrion: technical explanations PDF |
| Can a holding-force number stand in for lifting capacity? | Kanetec publishes lifting capacity separately from maximum holding power and notes that workpiece thickness and surface conditions matter. | For lifted loads, use a purpose-built lifting magnet with a published capacity and approval basis. | Kanetec catalog 098: lifting electromagnets |
| Can a magnetic gripper hold a non-ferromagnetic part? | Schmalz specifies ferromagnetic workpieces for its magnetic grippers and describes a 3:1 design safety factor. | Use a mechanical clamp, vacuum, or another method for non-ferromagnetic parts; check the selected gripper instructions for its rating basis. | Schmalz magnetic gripper operating instructions (09/2020) |
| Does “120 volt” identify one round-electromagnet coil type? | Industrial Magnetics lists 120 VAC and 110 VDC round models; these are separate supply classes. | Confirm the exact AC or DC model and request its own force, duty, and release data. | Industrial Magnetics: round electromagnets (24VDC, 110VDC, 120VAC) |
| What supply range should a nominal 120 V AC model be checked against? | USDA RUS guidance citing ANSI C84.1-2016 gives a 120 V Range A service window of 114-126 V; Range B service is 110-127 V for limited-duration tolerance. | Confirm hold and release behavior at the low and high supply conditions expected at the installation. | USDA RUS Bulletin 1724D-114 (Dec 2017, cites ANSI C84.1-2016) |
| Will every internally rectified 120 VAC magnet release electronically? | Magnetool says its 120 VAC line is rectified internally to 110 VDC and can retain up to 20% residual magnetism without a release pulse. | Confirm the release method for the exact model and test it on the production workpiece. | Magnetool: 120 V.A.C. electromagnets (updated Nov 2025) |
| What changes when a magnet is used on an overhead crane? | OSHA 1910.179 includes lifting-magnet circuit and rated-load test requirements for overhead and gantry cranes. | Have the responsible crane and safety professionals review the control circuit, test plan, and records before use. | OSHA 29 CFR 1910.179 overhead and gantry cranes |
| Which standards cover below-the-hook lifting devices? | ASME B30.20 covers safety requirements; ASME BTH-1 provides minimum structural, mechanical, and electrical design criteria. | Use both standards with the applicable site and jurisdictional requirements when the application is below-the-hook lifting. | ASME BTH-1 (2023): design of below-the-hook lifting devices |
Boundary triggers
These are hard stops, not soft suggestions.
| Trigger | Why this blocks | Required action |
|---|---|---|
| Workpiece is non-ferromagnetic | Force estimates from steel-based curves are invalid on non-ferromagnetic parts. Source: Schmalz magnetic gripper operating instructions (09/2020) | Move to mechanical clamp, vacuum, adhesive, or redesign with a ferromagnetic interface. |
| Ambient or duty context outside normal -5 to 40 °C assumptions | Published continuous-duty context no longer matches thermal conditions. Source: Kendrion: technical explanations PDF | Run part-level thermal and force validation before approving the selection. |
| Shear/sliding load without mechanical stop | Shifting force can be only 20-33% of nominal holding force. Source: Kendrion: technical explanations PDF | Add a hard mechanical stop or redesign so load direction is normal pull. |
| Use case is actual lifting, not static holding | Lifting systems use a different rating basis (lift capacity, not only holding force). Source: Kanetec catalog 098: lifting electromagnets | Use a purpose-built lifting magnet family with published lift-capacity basis. |
| 120 V service operates near low-line or high-line limits | ANSI C84.1 service windows show 120 V systems can run across a range, not a single fixed point. Source: USDA RUS Bulletin 1724D-114 (Dec 2017, cites ANSI C84.1-2016) | Validate hold and release behavior at both low-line and high-line service conditions before approval. |
| Selection expands to below-the-hook overhead lifting | This is no longer a generic holding-magnet decision; OSHA/ASME compliance gates apply. Source: OSHA 29 CFR 1910.179 overhead and gantry cranes | Route the project to B30.20/BTH-1 + OSHA 1910.179 review with documented testing and control-circuit checks. |
What public evidence still does not prove
Evidence-insufficient items are explicitly marked instead of forced into conclusions.
| Claim | Evidence status | Next action |
|---|---|---|
| Universal derating factor for painted or oxidized steel across all 12 V round magnets | No single cross-brand public force curve was found for this geometry and coating class. | Request pull data for your coating and contact geometry; compare candidates using the same workpiece conditions. |
| Public fatigue-cycle life curves for 11 lb-class round magnets under vibration + repeated release | No reliable public cycle-life dataset was found in the reviewed sources. | Treat cycle-life claims as unverified until the supplier provides an endurance test report for the expected vibration and release cycle. |
| Single public rule for release time after de-energizing across steel grades | Evidence is material-dependent: Kendrion reports residual-force behavior, but no universal timing curve was verified. | Measure release time on the production workpiece and record the acceptable release window. |
| Universal conversion rule from 12 V proxy force curves to all 120 VAC round-electromagnet models | Voltage classes are published, but no universal cross-brand conversion curve was verified. | Request 120 VAC / 110 VDC model-specific pull-force and release data before using 12 V proxy numbers for procurement decisions. |
| Public low-line/high-line force and release curves across the full ANSI C84.1 120 V service window | No reliable public cross-brand dataset was found for 114-126 V performance drift on round-electromagnet models. | Require supplier validation across the intended service-voltage range and archive the measured hold/release results in the RFQ file. |
Published Comparison
Representative products and what each one really proves
This is not a price table. It is a proof-model table. Each row explains what that published product family tells you about the round-electromagnet decision.
| Reference | Family | Published data | What it proves |
|---|---|---|---|
| Eclipse M52180/12VDC | Small energise-to-hold magnet | Revision January 2025 v2: 5.2 kg hold, 12 V, 210 mA, 2.4 W, 100% ED | This is what an 11 lb / 12 V class product actually looks like in a public datasheet. |
| Kendrion technical explanations | Holding-force behavior model | Shifting force 20-33%; residual force after deactivation around 20-40%; material baseline references include S235JR | Material, release behavior, and load direction are first-order boundaries, not optional fine tuning. |
| Kendrion GTB electro holding range | Industrial electro holding magnet | 36-30,000 N, 12/24 V, 100% ED | Industrial holding magnets exist well above hobby scale, but still assume proper armature and no unsupported gap. |
| Kendrion PEM permanent electro range | Permanent electro holding magnet | 8-3,500 N, currentless holding force, 25% ED | Power-fail-safe and low-energy hold are a separate family decision. |
| Kendrion door holding range | Door hold-open magnet | 24 V DC, 300-1,568 N, EN1155 / EN14637 context | Door hardware is not the same selection problem as small part holding. |
| Schmalz magnetic gripper instructions | Magnetic handling rule set | Operating guide 09/2020: ferromagnetic-only workpieces and safety factor S=3 for horizontal transport | Tool output must block non-ferromagnetic parts and keep conservative working-load assumptions. |
| Kanetec LMU-UW lifting electromagnet | Purpose-built lifting magnet | Lift capacity rated as half of maximum holding power; smallest listed capacity 600 kg; plate-thickness condition notes included | Real lifting systems publish lift ratings and backup logic instead of only quoting holding force. |
| Industrial Magnetics round electromagnet page | Voltage-class catalog boundary | Round electromagnets listed in 24 VDC, 110 VDC, and 120 VAC configurations with model-level WLL values. | Voltage class and working-load language are published as distinct procurement fields, not interchangeable labels. |
| Magnetool 120 V.A.C. electromagnets | 120 VAC release behavior boundary | 120 VAC input internally rectified to 110 VDC; residual magnetism up to 20% without release pulse; built-in path does not provide electronic release function. | For AC branch decisions, release behavior must be validated explicitly instead of inferred from nominal voltage. |
| USDA RUS Bulletin 1724D-114 / ANSI C84.1-2016 | Service-voltage boundary for 120 V systems | 60 Hz 120 V class windows include Range A service 114-126 V and Range B service 110-127 V (limited duration). | “120 V” is an operating range, so hold/release checks need edge-voltage validation. |
| OSHA 1910.179 + ASME B30.20/BTH-1 | Below-the-hook lifting governance | OSHA defines magnet controls/testing expectations; ASME B30.20 and BTH-1 define operation and design framework for below-the-hook devices. | Once use case becomes overhead lifting, compliance evidence is mandatory before quote or installation approval. |
Risk and Boundaries
The main failure modes are predictable
The point of this section is not to scare the user away from holding magnets. The point is to make the predictable failure modes visible before someone orders the wrong family.
Risk matrix
Impact and mitigation are included so the table can drive a next action instead of acting like filler.
| Risk | Impact | What public evidence says | Mitigation |
|---|---|---|---|
| Treating 120V intent as interchangeable with 12V proxy math | High | Industrial Magnetics publishes separate 120 VAC and 110 VDC round models, and Magnetool documents residual-force behavior specific to 120 VAC round designs. | Branch the review by coil class first, then apply model-specific pull and release data before approval. |
| Using nominal 120 V as a fixed value instead of a service window | Medium | USDA guidance citing ANSI C84.1-2016 shows 120 V service can operate across 114-126 V (Range A), with wider Range B tolerated for limited duration. | Test hold and release behavior at low-line and high-line service conditions before sign-off. |
| Assuming built-in rectified 120 VAC models always release cleanly | High | Magnetool states 120 VAC units are internally rectified to 110 VDC, do not provide electronic release through the built-in rectifier path, and may retain up to 20% residual magnetism. | Specify release method in RFQ and verify de-energized release behavior on the production workpiece. |
| Treating catalog force as lifted weight | High | The Eclipse 20 mm example loses about 60% at 0.09 mm gap, and Kanetec halves holding power to publish lift capacity on lifting magnets. | Use the checker, then verify the real working load on the production steel face before approval. |
| Shear or vibration | High | Kendrion publishes shifting force at 20-33% of holding force. | Add a mechanical stop or redesign so the magnet sees a normal pull-off load instead of a sliding load. |
| Unexpected release lag after power-off | Medium | Kendrion technical notes indicate residual force after deactivation can remain around 20-40% depending on the workpiece. | Validate release behavior on the real part and add an active separation strategy when fast release is required. |
| Power outage releases the load | High | Standard energise-to-hold magnets release when power is removed, while permanent electro ranges publish safe holding during power failure. | Move to a permanent electro family or add a mechanical fail-safe. |
| Material mismatch versus published baseline | High | Kendrion ties reference force values to specific steel conditions (for example S235JR) and warns hardening can reduce permeability. | Treat unknown/hardened materials as boundary cases and require part-level testing before sign-off. |
| Long continuous hold outside thermal assumptions | Medium | Eclipse recommends energise-to-release magnets for long continuous powering; Kendrion cites normal duty assumptions around -5 to 40 °C. | Switch families for long hold duty or validate thermal behavior under real ambient conditions. |
| Wrong product family for the job | High | Door magnets, holding magnets, magnetic grippers, and lifting magnets publish different proof, voltages, and safety logic. | Use the family-comparison table before asking suppliers for price or lead time. |
| Treating overhead lifting as a normal fixture-hold decision | High | OSHA 1910.179 and ASME B30.20/BTH-1 place crane-lifting magnets under specific control, testing, and design frameworks. | Trigger compliance review (rated-load testing, control-circuit checks, and standards traceability) before procurement. |
One visual summary
Most mistakes are family mistakes
The tool can screen force, but the report layer matters because the biggest errors happen when buyers compare holding magnets against door magnets or lifting magnets as if they are interchangeable SKUs. They are not.
Fast rule
If a dropped part would be unsafe, if power loss cannot release the load, or if the part slides instead of pulling off normally, do not approve the small holding magnet from headline force alone.
Scenario checks
These examples translate the tool output into real selection language.
| Scenario | Inputs | Checker reading | Conclusion |
|---|---|---|---|
| Bench fixture on flat steel coupon | 11 lb catalog force, 0.00 mm gap, flat steel, direct pull, 1.5 lb target | About 3.7 lb conservative working load after a 3:1 safety factor | Reasonable place to prototype a simple holding magnet if dropped parts are low consequence. |
| Painted panel retention | 11 lb catalog force, 0.18 mm gap, painted steel, direct pull, 2.0 lb target | Roughly 0.3 lb working load equivalent after derating | Fails quickly because paint plus gap destroys the small-magnet headline. |
| Sliding steel tag in automation | 11 lb catalog force, 0.09 mm gap, clean steel, shear load, 1.0 lb target | About 0.3 lb working load equivalent after shear derating | Not acceptable without a mechanical stop; the sliding condition is the real blocker. |
| Long hold-open duty with power-loss concern | 11 lb class magnet, 3.0 hour hold time, release on outage not allowed | Force may exist, but family choice changes to permanent electro or door magnet | This is no longer a small electro holding magnet decision at all. |
| 120 VAC branch with low-line supply and release-critical timing | 120 VAC request, service may vary across 114-126 V, clean release required after de-energizing | Boundary status: nominal-force math is insufficient until low/high-line release behavior is validated on the actual workpiece | Use 120 VAC model data plus release-test evidence; do not approve from nominal 120 V label alone. |
| Plant request says “120 volt round electromagnet” with unknown coil class | 120 V request, 0.09 mm gap estimate, static hold target, AC/DC class not confirmed | Boundary status: force estimate is directional only until 120 VAC or 110 VDC model data is confirmed | Do not release RFQ on keyword alone. Confirm coil class, release behavior, and voltage-specific pull data first. |
Secondary CTA
Need supplier-proof checks before RFQ?
Send your part material, target load, expected air gap, and load direction. We will flag boundary risks before you commit to a round-electromagnet family.
FAQ
Round electromagnet questions that change buying decisions
These are grouped by decision intent rather than glossary trivia so the FAQ section still helps a technical buyer move forward.
Fit and Numbers
Choosing the Right Family
Electrical and Sourcing
Next Step
Use the checker, then ask for the right proof
The fastest way to waste time on round electromagnets is to request quotes before you know the family, the air-gap basis, or the fail-safe requirement. Use this page to narrow the problem first.
Main CTA
Need a custom round-electromagnet review?
Send the exact part number, target load, steel face condition, gap estimate, and whether power-fail-safe hold is required. That is enough to tell whether you need a holding magnet, a permanent electro family, or something closer to a lifting system.
Sources
Reviewed October 11, 2026
Eclipse Magnetics M52xxx datasheet (January 2025 v2)Kendrion: electro holding magnetsKendrion: technical explanations PDFKendrion: permanent electro holding magnetsKendrion: door holding magnetsSchmalz magnetic gripper operating instructions (09/2020)Kanetec catalog 098: lifting electromagnetsIndustrial Magnetics: round electromagnets (24VDC, 110VDC, 120VAC)Magnetool: 120 V.A.C. electromagnets (updated Nov 2025)Magnetool: round lifting magnets (110 VDC, 2:1 safety-factor ratings)USDA RUS Bulletin 1724D-114 (Dec 2017, cites ANSI C84.1-2016)OSHA 29 CFR 1910.179 overhead and gantry cranesASME B30.20 (2025): below-the-hook lifting devicesASME BTH-1 (2023): design of below-the-hook lifting devices