Custom MI heating cables with soldered cold leads
Finished Soldered MI Assemblies
Pro Therm assembles mineral-insulated heating cables with soldered cold leads in its own workshop. We match the heated section, connection lengths and construction to your specification – for plant builders, operators and international project partners.
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Ready-to-connect heating assemblies
Request a heating circuit manufactured to your specification, with a defined heated section and suitable cold leads. The transitions are prepared and soldered in our …
Request a heating circuit manufactured to your specification, with a defined heated section and suitable cold leads. The transitions are prepared and soldered in our workshop. Specify the heated length and the required connection lengths in your enquiry.
A cable designation alone does not define a finished circuit. Voltage, resistance, output, installation conditions and temperatures must be considered together. We agree the construction with you before manufacture.
A ready-to-connect unit is specified as one assembly: heated section, transitions, cold-lead ends and termination arrangement. The resistance cable must match length, voltage and required output. A unique assembly reference supports repeat orders and makes changes to length, cold leads or terminations traceable.
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NiCr heating-conductor types
The existing single-core range with a NiCr heating conductor and stainless steel sheath includes: CrNi 10-32: 10 Ω/m · Ø 3.2 mm CrNi 6.3-32: 6.3 Ω/m · Ø 3.2 mm CrNi …
The existing single-core range with a NiCr heating conductor and stainless steel sheath includes:
CrNi 10-32: 10 Ω/m · Ø 3.2 mm CrNi 6.3-32: 6.3 Ω/m · Ø 3.2 mm CrNi 4.0-32: 4.0 Ω/m · Ø 3.2 mm CrNi 2.5-34: 2.5 Ω/m · Ø 3.4 mm CrNi 1.6-36: 1.6 Ω/m · Ø 3.6 mm CrNi 1.0-39: 1.0 Ω/m · Ø 3.9 mm CrNi 0.63-43: 0.63 Ω/m · Ø 4.3 mm CrNi 0.4-47: 0.4 Ω/m · Ø 4.7 mm CrNi 0.25-53: 0.25 Ω/m · Ø 5.3 mm
Temperature and voltage limits are checked for the specific cable type and finished heating assembly.
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Request your specified assembly
Choose a known cable type or request selection by Pro Therm. For a finished MI assembly, the key inputs are heated length, supply voltage, both cold-lead lengths and …
Choose a known cable type or request selection by Pro Therm. For a finished MI assembly, the key inputs are heated length, supply voltage, both cold-lead lengths and quantity.
Add the application, maintain and maximum exposure temperatures, destination country and requested date. For a replacement circuit, include the existing identification and available measurements or design information. Unknown details can be marked as open.
A drawing with the heating length and separate dimensions for cold-lead ends A and B helps coordination. Please distinguish specified values from measurements of an existing unit. Marking, destination country and agreed test or documentation requirements are clarified before assembly.
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Agree testing and unambiguous identification
Before manufacture, the drawing revision, heated length, both cold-lead sides, connection arrangement and requested identification are aligned. Resistance values need a …
Before manufacture, the drawing revision, heated length, both cold-lead sides, connection arrangement and requested identification are aligned. Resistance values need a defined reference temperature or the corresponding product data. Electrical tests, records and tolerances included in the supply are agreed in the order.
For replacement and repeat orders, a unique assembly reference links the delivered configuration to its design data. Ex suitability or local approval is assessed for the specifically confirmed assembly and intended use; it is not inferred from the metallic sheath alone.
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Frequently asked questions
What does supplied with soldered cold leads mean? The heated section and cold leads are joined in our workshop to the agreed specification. The assembly is supplied with …
What does supplied with soldered cold leads mean?
The heated section and cold leads are joined in our workshop to the agreed specification. The assembly is supplied with the agreed termination and documentation scope. Installation and electrical connection follow the corresponding instructions.
Do I need to know the cable type?
No. You can request selection by Pro Therm. Describe the application, temperatures, supply and required geometry. For a replacement, include the existing identification and previous design information.
Can I request different cold-lead lengths?
Yes. Specify cold lead A and cold lead B separately. We review the requested construction together with cable type, output, current and connection conditions.
What information is needed for an international enquiry?
State the destination and operating country, supply voltage, application, temperatures, quantity and requested date. Add required approvals, marking and documentation language. Suitability and supply scope are confirmed for the specific assembly.
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Related topics
High-temperature heating → Hazardous-area heat tracing → Heat-up → Controls and monitoring → Worldwide installation → Heat loss and insulation →
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Constantan heating-conductor types
The existing single-core range with a stainless steel sheath includes the following catalogue types. Values show resistance per metre and outside diameter: CrNi 1.6-32: …
The existing single-core range with a stainless steel sheath includes the following catalogue types. Values show resistance per metre and outside diameter:
CrNi 1.6-32: 1.6 Ω/m · Ø 3.2 mm CrNi 1.0-34: 1.0 Ω/m · Ø 3.4 mm CrNi 0.63-37: 0.63 Ω/m · Ø 3.7 mm CrNi 0.4-40: 0.4 Ω/m · Ø 4.0 mm CrNi 0.25-44: 0.25 Ω/m · Ø 4.4 mm
Selection uses the complete design and the corresponding datasheet.
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Cold leads and connection lengths
The existing range describes two single-core cold-lead constructions with a copper conductor: Copper sheath: 2.5 mm² · Ø 5.3 mm Stainless steel sheath: 2.5 mm² · Ø 5.3 …
The existing range describes two single-core cold-lead constructions with a copper conductor:
Copper sheath: 2.5 mm² · Ø 5.3 mm Stainless steel sheath: 2.5 mm² · Ø 5.3 mm Catalogue resistance for both: 0.00690 Ω/m.
Specify cold lead A and cold lead B separately, measuring the route from the heated section to the intended connection. Sheath material, transitions and termination details are matched to the surroundings and your requirements.
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Supply scope for your project
For international enquiries, we consider the technical specification together with requirements at the place of use. State the required identification, documentation …
For international enquiries, we consider the technical specification together with requirements at the place of use. State the required identification, documentation language, test records and any hazardous-area requirements. The agreed supply scope is recorded in the quotation.
Recurring requirements can also be referenced by an agreed heating-circuit or item identifier. Availability, delivery date and any required installation work are reviewed for the individual order.
Your requirements guide the selection: tell us your preferred brand and budget range. For the complete system, we also work independently of a single manufacturer and select technically suitable heating, termination and control components for your project.
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Standards and technical basis
Our knowledge section explains how the standards relate to the heating task, product selection and project design. Open the standards overview →
Our knowledge section explains how the standards relate to the heating task, product selection and project design.
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Enquire about a finished soldered MI assembly
Use the enquiry form to specify heating length, voltage, output, cold-lead ends A/B and quantity. Add drawings, temperatures, termination requirements and destination …
Use the enquiry form to specify heating length, voltage, output, cold-lead ends A/B and quantity. Add drawings, temperatures, termination requirements and destination country. We assess the combination and agree the assembly with you.
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References & projects
Explore our project reports for electric heat tracing and frost heave protection. View references & projects →
Explore our project reports for electric heat tracing and frost heave protection.
Constantan heating-conductor types
The existing single-core range with a stainless steel sheath includes the following catalogue types. Values show resistance per metre and outside diameter:
CrNi 1.6-32: 1.6 Ω/m · Ø 3.2 mm
CrNi 1.0-34: 1.0 Ω/m · Ø 3.4 mm
CrNi 0.63-37: 0.63 Ω/m · Ø 3.7 mm
CrNi 0.4-40: 0.4 Ω/m · Ø 4.0 mm
CrNi 0.25-44: 0.25 Ω/m · Ø 4.4 mm
Selection uses the complete design and the corresponding datasheet.
NiCr heating-conductor types
The existing single-core range with a NiCr heating conductor and stainless steel sheath includes:
CrNi 10-32: 10 Ω/m · Ø 3.2 mm
CrNi 6.3-32: 6.3 Ω/m · Ø 3.2 mm
CrNi 4.0-32: 4.0 Ω/m · Ø 3.2 mm
CrNi 2.5-34: 2.5 Ω/m · Ø 3.4 mm
CrNi 1.6-36: 1.6 Ω/m · Ø 3.6 mm
CrNi 1.0-39: 1.0 Ω/m · Ø 3.9 mm
CrNi 0.63-43: 0.63 Ω/m · Ø 4.3 mm
CrNi 0.4-47: 0.4 Ω/m · Ø 4.7 mm
CrNi 0.25-53: 0.25 Ω/m · Ø 5.3 mm
Temperature and voltage limits are checked for the specific cable type and finished heating assembly.
Cold leads and connection lengths
The existing range describes two single-core cold-lead constructions with a copper conductor:
Copper sheath: 2.5 mm² · Ø 5.3 mm
Stainless steel sheath: 2.5 mm² · Ø 5.3 mm
Catalogue resistance for both: 0.00690 Ω/m.
Specify cold lead A and cold lead B separately, measuring the route from the heated section to the intended connection. Sheath material, transitions and termination details are matched to the surroundings and your requirements.
Request your specified assembly
Choose a known cable type or request selection by Pro Therm. For a finished MI assembly, the key inputs are heated length, supply voltage, both cold-lead lengths and quantity.
Add the application, maintain and maximum exposure temperatures, destination country and requested date. For a replacement circuit, include the existing identification and available measurements or design information. Unknown details can be marked as open.
A drawing with the heating length and separate dimensions for cold-lead ends A and B helps coordination. Please distinguish specified values from measurements of an existing unit. Marking, destination country and agreed test or documentation requirements are clarified before assembly.
Supply scope for your project
For international enquiries, we consider the technical specification together with requirements at the place of use. State the required identification, documentation language, test records and any hazardous-area requirements. The agreed supply scope is recorded in the quotation.
Recurring requirements can also be referenced by an agreed heating-circuit or item identifier. Availability, delivery date and any required installation work are reviewed for the individual order.
Your requirements guide the selection: tell us your preferred brand and budget range. For the complete system, we also work independently of a single manufacturer and select technically suitable heating, termination and control components for your project.
Standards reference (checked 14 October 2026): IEC/IEEE 60079-30-1:2025 and IEC/IEEE 60079-30-2:2025 are international references for resistance trace heating in hazardous areas. Germany still lists DIN EN 60079-30-1:2018-04 and DIN EN 60079-30-2:2018-04 as current national editions. Equipment group, permitted EPL, protection concept and evidence for the actual assembly determine suitability.