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How to Spec a Custom HV Insulation or Barrier Part: What to Send H-O for a Quote
A fast, accurate quote on a custom die-cut electrical-insulation or dielectric-barrier part comes down to a handful of inputs: the job the part does, the continuous working voltage and the dielectric test level, the creepage and clearance the layout needs, the thermal class, any flammability or arc duty, the gauge or thickness, the mechanical or clamping requirement, the geometry and a drawing, and your prototype and annual volumes.
This guide walks each input, explains why it matters, and ends with a spec builder that assembles your answers into a request you can paste straight into the quote form. H-O matches a family and a grade direction, confirms grade values against the manufacturer's current technical data sheet, and converts to your drawing; it does not certify the finished apparatus.
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The application problem: an incomplete spec stalls the quote
H-O Products is a precision die-cut converter, and every insulation or barrier part is made to order from sheet, roll, board, or slab stock cut to your drawing. The concrete problem a buyer runs into is the stalled quote: a request that says "I need a dielectric barrier" without the working voltage, the test level, or the thermal class cannot be turned into a family, a grade direction, and a price without a follow-up.
The inputs below are the same ones an applications engineer would ask for, so sending them up front turns a back-and-forth into a single response.
The first input does the most work. As covered in the companion guide on choosing a dielectric family, the part is either a thin solid dielectric barrier between conductors, a rigid creepage-and-clearance barrier or standoff, a flexible slot or layer liner, or an arc-flash or fire barrier. The rest of the spec branches from that answer, because a film, a rigid laminate, a paper, and an inorganic barrier are sized and converted differently.
Why it is challenging: the inputs come in pairs and the apparatus owns the type test
Specifying these parts is harder than listing dimensions because several of the most important inputs are pairs, not single numbers, and because the qualifying tests belong to the assembly rather than the part. The working voltage and the dielectric test level travel together, because the solid-insulation thickness is selected for the test level, not just the nameplate voltage, and dielectric strength is thickness-dependent (the test method is IEC 60243 / ASTM D149).
Creepage and clearance travel together with the pollution degree and overvoltage category, because those set the distances the barrier has to hold (IEC 60664-1). And the apparatus-level dielectric-withstand and type tests are a result the finished switchgear, transformer, or machine earns under its own standard (IEC 62271, IEC 60076, or IEC 60034), not a property of the converted part.
The checklist below is organized around those realities.
What to send, input by input
1. The job, and the family it points to
- Thin solid dielectric barrier: a film or paper layer interposed between conductors. Points toward polyimide film, PEEK film, or aramid paper.
- Rigid creepage / clearance barrier or standoff: a load-bearing barrier that lengthens the surface path and breaks the air path. Points toward glass-laminate (GPO-3 class) or Durostone-class composite.
- Flexible slot or layer liner: thin, flexible, high-thermal-class insulation. Points toward aramid paper or polyimide film.
- Arc-flash or fire barrier: an inorganic or flame-rated barrier. Points toward mica barrier sheet, glass-fiber paper, or flame-retardant silicone sponge for a compressible barrier.
2. Working voltage and dielectric test level
Send the continuous working voltage and the dielectric test (hipot) level the part has to support, together. The solid-insulation thickness is selected for the test level, and dielectric strength is thickness-dependent, so the gauge and the test method (IEC 60243 / ASTM D149) belong with the voltage. Naming a voltage without the test level still leaves the thickness open.
3. Creepage and clearance
State the creepage and clearance the layout requires, with the pollution degree and overvoltage category behind them (IEC 60664-1). These set the profile a rigid barrier has to hold to lengthen the surface path and break the air path. If a barrier is being added specifically to fix a shortfall, say which distance falls short.
4. Thermal class
Give the thermal class the part must meet at the system hot spot (IEC 60085), not the ambient. The class steers the family: aramid paper is commonly associated with Class F and H systems, polyimide film carries a very high thermal class for a polymer, and inorganic mica reaches the highest classes. Name the class rather than a temperature in isolation.
5. Flammability and arc duty
If the part sits in a flammability-controlled or arc-flash zone, name the requirement. A flame rating is called out as a standard such as UL 94 V-0 (with relative thermal index per UL 746B where long-term temperature endurance matters), not as "fireproof." The arc-flash boundary itself is a system-level study (IEEE 1584 / NFPA 70E); H-O supplies the barrier material, not the boundary analysis.
6. Gauge or thickness, and mechanical or clamping need
Send the gauge or thickness range and any mechanical duty: whether a barrier or standoff is clamped or compressed, carries a load, or sees vibration. Thickness is part of the dielectric spec because dielectric strength is thickness-dependent; the mechanical duty decides whether the part is a rigid laminate or a flexible layer.
7. Prototype and annual volume
Share both the prototype quantity and the expected annual volume. All parts are custom manufactured to order, and minimum production run quantities apply, so the volume shapes the converting approach and the tooling decision. Prototype quantities through full production are welcome.
8. The drawing
A dimensioned drawing closes the loop. Send a DXF, STEP, or PDF with the footprint, gauge, hole and slot pattern, the creepage-defining profile, tolerances, and any adhesive callouts. If you do not have a formal drawing yet, a marked-up sketch with dimensions is enough to start a prototype.
The spec at a glance
| Input | Thin barrier / liner | Rigid barrier / standoff | Arc / fire barrier |
|---|---|---|---|
| Electrical | Working voltage + test level; gauge (dielectric strength per IEC 60243 / ASTM D149) | Working voltage; creepage + clearance + pollution degree + overvoltage category (IEC 60664-1) | Working voltage; barrier role in the arc / fire zone |
| Thermal | Thermal class at the hot spot (IEC 60085) | Thermal class; grade-dependent | High thermal endurance (inorganic) |
| Compliance | UL 94 if flame-rated; RTI per UL 746B if needed | Assembly per IEC 61439 / IEC 62271 | UL 94 V-0; arc-flash boundary per IEEE 1584 / NFPA 70E (system) |
| Mechanical | Gauge / thickness range | Clamping / load / vibration; profile | Compressible or rigid; thickness |
| Commercial | Prototype quantity + annual volume; drawing (DXF / STEP / PDF) | ||
HV Insulation & Barrier RFQ Spec Builder
Job: Thin dielectric barrier / liner (film or paper between conductors) Electrical: working voltage and dielectric test (hipot) level — to be provided; gauge sets the dielectric withstand (thickness-dependent, per IEC 60243 / ASTM D149) Creepage / clearance: to be provided (with pollution degree, per IEC 60664-1) Thermal class: to be provided (at the system hot spot, IEC 60085) Compliance: none stated Mechanical: gauge / thickness range — to be provided Commercial: prototype quantity + annual volume — to be provided Drawing: to follow Note: H-O converts to drawing and confirms grade values on the current TDS; apparatus-level type tests belong to the equipment maker.
Illustrative only; confirm against current material data and a drawing review. This builder formats your inputs into a request; it does not select a grade, set a thickness, or assign a kilovolt-per-millimeter withstand or a dielectric-test result. Dielectric strength is thickness-dependent and is confirmed per IEC 60243 / ASTM D149 on the manufacturer's current technical data sheet; required creepage and clearance come from IEC 60664-1; the apparatus-level withstand and type tests are performed by the equipment maker on the finished assembly.
Common failure modes in the spec itself
| Spec gap | Why it stalls the quote | The fix |
|---|---|---|
| "A dielectric barrier," no voltage | Family and gauge cannot be set without the working voltage and test level | Send the working voltage and dielectric test level together |
| A voltage but no test level | Thickness is set by the test level, and dielectric strength is thickness-dependent | Add the hipot / dielectric test level and the test method (IEC 60243 / ASTM D149) |
| "Make it pass hipot at the assembly" | The apparatus type test is a system result, not a property of the converted part | Specify the part's gauge and material grade; type-test the finished assembly |
| "Fireproof" barrier | Not a grade designation; the right flame-rated material is ambiguous | Name the standard, for example UL 94 V-0 (and RTI per UL 746B if needed) |
| Temperature with no class | A bare temperature does not map cleanly to a thermal-class family | State the thermal class at the hot spot (IEC 60085) |
| No volumes | The converting and tooling approach depends on prototype versus production scale | Send both prototype quantity and annual volume |
How H-O Products helps
H-O Products is a precision die-cut converter. Once your spec is complete, we recommend a material family and grade direction across mica barrier sheet, polyimide and PEEK film, aramid paper, glass-fiber paper, and glass-laminate (GPO-3 class and the glass-epoxy grades), then convert the stock to your drawing: die-cut, kiss-cut, laser or waterjet cut, machined to a profile, laminated, slit to width, and kitted.
Documentation available on request includes the material technical data sheet, a certificate of conformance, lot traceability, and first-article inspection, all under our ISO 9001:2015 certified quality management system. We hold converting tolerances to the drawing; we do not produce the raw stock, and we do not certify the finished switchgear, transformer, machine, or battery pack. Grade properties are confirmed against the manufacturer's current technical data sheet, and the apparatus-level withstand and type tests belong to the equipment maker.
Send the spec, get a quote
Use the builder above to assemble your request, then paste it into the quote form with your drawing attached. We will recommend a family and grade direction and convert samples on your footprint.
Samples typically ship in 3 to 5 business days for common die-cut configurations; standard production runs about two weeks; special orders are quoted to the job.
Family-owned in Winsted, Connecticut since 1971 · ISO 9001:2015 certified · OEMs worldwide send us a drawing — and get back their part.
Related reading
Frequently asked questions
What information does H-O need to quote a custom insulation or barrier part?
Send the job (thin barrier or liner, rigid creepage and clearance barrier or standoff, or arc-flash and fire barrier); the continuous working voltage and the dielectric test (hipot) level together; the creepage and clearance with the pollution degree and overvoltage category; the thermal class at the system hot spot; any flammability (UL 94 V-0) or arc-flash requirement; the gauge or thickness and any mechanical or clamping duty; prototype quantity and annual volume; and a drawing in DXF, STEP, or PDF.
H-O matches a family and grade direction and converts to drawing; apparatus type tests belong to the equipment maker.
Why do you need the dielectric test level and not just the working voltage?
The solid-insulation thickness is selected for the dielectric test (hipot) level, not the nameplate working voltage alone, and dielectric strength is thickness-dependent (tested per IEC 60243 / ASTM D149). Sending the working voltage and the test level together lets the gauge and material grade direction be set in one pass rather than after a follow-up.
Can H-O certify that my switchgear or transformer passes its dielectric test?
No. H-O qualifies the converted part to the drawing (dimensions, gauge, and material grade) under an ISO 9001:2015 certified quality management system. The apparatus-level dielectric-withstand and type tests are performed by the equipment maker on the finished assembly under its own standard, for example IEC 62271 for switchgear, IEC 60076 for transformers, or IEC 60034 for rotating machines.
Does H-O have a minimum order quantity?
All parts are custom manufactured to order and minimum production run quantities apply, varying by material and part. Prototype quantities through full production are welcome, so sending both the prototype quantity and the expected annual volume lets H-O recommend the right converting and tooling approach.
Request a quote for your high-voltage dielectric & insulation part
Send H-O your drawing or describe the part—engineering reviews every RFQ and converts samples on your geometry.
Last updated · Reviewed by H-O Products engineering (ISO 9001:2015 certified converter, Winsted, CT).
References
- IEC 60243-1 and ASTM D149 (dielectric strength of solid insulating materials). IEC / ASTM International.
- IEC 60664-1 (insulation coordination: clearance and creepage). IEC.
- IEC 60112 (Comparative Tracking Index) and IEC 60085 (thermal classification). IEC.
- UL 94 (flammability) and UL 746B (relative thermal index). UL Standards.
- IEEE 1584 and NFPA 70E (arc-flash hazard at the system level). IEEE / NFPA.
- Manufacturer technical data sheets: polyimide film, aramid paper, mica, GPO-3 and glass-epoxy laminates, and silicone sponge grades named in this article.
This article cites general engineering principles and published standards (IEC 60243-1 and ASTM D149 for dielectric strength, IEC 60664-1 for insulation coordination, IEC 60112 for Comparative Tracking Index, IEC 60085 for thermal classification, UL 94 for flammability, UL 746B for relative thermal index, IEEE 1584 and NFPA 70E for arc-flash hazard at the system level, and the apparatus standards IEC 62271, IEC 60076, and IEC 60034).
Material names refer to material families H-O Products converts. Dielectric strength is thickness-dependent and is confirmed per the test method on the manufacturer's current technical data sheet; no kilovolt-per-millimeter withstand value is stated here for any grade. All parts are custom manufactured to order and minimum production run quantities apply. H-O is a die-cut converter, not a raw-material producer, and does not certify the finished apparatus.