Electri Terminal

Engineering Reference Guide

Terminal Type, Insulation & Stud Size Guide

Match terminal type, insulation code, wire-size interval, and stud dimensions with structured tables designed for engineering selection.

Start with Terminal TypeRequest Quote
Type referenceInsulation codesStud size matching
Terminal model naming diagram
Terminal naming structure
Connector model naming diagram
Connector naming structure

Quick Reference Sections

Terminal Type

Decode model families and type codes.

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Insulation + Color/Wire

Confirm insulation style and stable wire ranges.

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Stud Size

Match stud and hole dimensions.

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AWG + mm2 Guide

Compare cable diameters and convert AWG to mm2.

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Sources

Review standards and manufacturer references.

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How to Use This Guide

For reliable selection, first identify terminal form, then confirm insulation and wire interval, and finally verify stud compatibility for installation.

  1. 1. Identify terminal form and code.
  2. 2. Match insulation code with stable wire range.
  3. 3. Confirm stud and hole size before final model lock.
Terminal TypeInsulation + Color/WireStud SizeAWG + mm2 GuideSources

Section A

Terminal Type Reference

Use terminal form and model code as the first filter before checking insulation or mounting dimensions.

Mobile view: card layout for faster scanning.

Ring Terminals

R
Insulation Code Ref
NYD
Wire Size Ref
1.25
Size Ref
-
Tongue Width Ref
3.7

Spade Terminals

S
Insulation Code Ref
D
Wire Size Ref
2
Size Ref
-
Tongue Width Ref
4

Locking Spade Terminals

LS
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

Flange Spade Terminals

FS
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

Hook Terminals

H
Insulation Code Ref
NY
Wire Size Ref
5.5
Size Ref
-
Tongue Width Ref
5

Blade Terminals

DB
Insulation Code Ref
E
Wire Size Ref
0.2
Size Ref
-
Tongue Width Ref
6

Lipped Blade Terminals

LB
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

Pin Terminals

PT
Insulation Code Ref
V
Wire Size Ref
1.25
Size Ref
-
Tongue Width Ref
10

Flag Terminals

FG
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

DIN-Ring Terminals

DR
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

DIN-Spade Terminals

DS
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

Female Disconnects

FD
Insulation Code Ref
NYD
Wire Size Ref
5.5
Size Ref
250
Tongue Width Ref
-

Male Disconnects

MD
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

Female Disconnects - Fully Insulated

FDF
Insulation Code Ref
NYD
Wire Size Ref
2
Size Ref
250
Tongue Width Ref
-

Flag Female Disconnects

FLD
Insulation Code Ref
NYD
Wire Size Ref
1.25
Size Ref
250
Tongue Width Ref
-

Piggy Back Disconnects

PBD
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

Female Receptacle Disconnects

FR
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

Male Bullet Disconnects

MP
Insulation Code Ref
-
Wire Size Ref
-
Size Ref
-
Tongue Width Ref
-

Closed End Connectors

CE
Insulation Code Ref
-
Wire Size Ref
1.25
Size Ref
-
Tongue Width Ref
-

Butt Connectors

B
Insulation Code Ref
V
Wire Size Ref
2
Size Ref
-
Tongue Width Ref
-

Cord End Terminals

E
Insulation Code Ref
-
Wire Size Ref
75
Size Ref
12
Tongue Width Ref
-

Double Line Cord End Terminals

TE
Insulation Code Ref
-
Wire Size Ref
10
Size Ref
08
Tongue Width Ref
-

The type codes and example dimensions in this table are Electri Terminal factory references, not universal designation codes. General product terminology and crimp connection context can be cross-checked against IEC 60352-2 [1], DIN 46234 [3], and DIN 46237 [4].

Wire terminal types, uses & identification guide

Section B

Insulation & Color/Wire Reference

Confirm insulation category first, then match wire-size intervals from stable color ranges.

Mobile view: card layout for faster scanning.

Nylon Insulated - Single Crimp

NY
Insulation Material
Nylon
Temperature Rating
105 C

Vinyl Insulated - Double Crimp

D
Insulation Material
Vinyl
Temperature Rating
75 C

Vinyl Insulated - Single Crimp

V
Insulation Material
Vinyl
Temperature Rating
75 C

Non-Insulated with Brazed Seam

NB
Insulation Material
None
Temperature Rating
-

Temperature ratings are product-family ratings and must be verified on the target datasheet. Comparable published examples include ABB vinyl-insulated terminals at 75°C [9] and TE PIDG terminal families up to 105°C [10]; these references support the material-and-temperature context but do not certify Electri Terminal item numbers.

Typical Insulation Structures

Visual comparison of common insulation structures used across terminal families.

nylon insulated ring terminal NY type

NY TYPE

Nylon Insulated - Single Crimp

Higher temperature resistance and improved durability for general applications.

vinyl insulated crimp terminal D type

D TYPE

Vinyl Insulated - Double Crimp

Enhanced insulation and mechanical support for secure crimping.

vinyl insulated ring terminal V type

V TYPE

Vinyl Insulated - Single Crimp

Standard insulation for general-purpose electrical connections.

non insulated brazed seam terminal NB type

NB TYPE

Non-Insulated - Brazed Seam

For direct metal contact and high-strength mechanical performance.

non insulated butted seam terminal N type

N TYPE

Non-Insulated - Butted Seam

Basic non-insulated structure for cost-sensitive applications.

PVC insulated easy entry sleeve terminal VE type

VE TYPE

PVC Insulated with Easy Entry Sleeve

Simplifies wire insertion during crimping.

PC insulated double crimp terminal FD type

FD TYPE

PC Insulated - Double Crimp

Improved rigidity and structural support for demanding applications.

nylon insulated double crimp terminal NYD type

NYD TYPE

Nylon Insulated - Double Crimp

Nylon sleeve with reinforced double-crimp retention for stable connections.

Main selection range keeps stable source intervals up to 60.57 mm2. Large-conductor tail segments at and above 76.28 mm2 are excluded from the main table pending data review.

Mobile view: card layout for faster scanning.

Yellow

AWG 26-22
Wire Size (mm2)
0.10-0.40
Max Current (A)
9
Notes
Small-gauge insulated range.

Red

AWG 20
Wire Size (mm2)
0.25-1.65
Max Current (A)
12
Notes
-

Blue

AWG 18
Wire Size (mm2)
1.04-2.63
Max Current (A)
17
Notes
-

Black

AWG 16
Wire Size (mm2)
2.63-4.60
Max Current (A)
19
Notes
-

Black

AWG 14
Wire Size (mm2)
2.63-4.60
Max Current (A)
27
Notes
-

Yellow

AWG 12
Wire Size (mm2)
2.63-6.64
Max Current (A)
37
Notes
-

Yellow

AWG 10
Wire Size (mm2)
2.63-6.64
Max Current (A)
48
Notes
-

Red

AWG 8
Wire Size (mm2)
6.64-10.52
Max Current (A)
62
Notes
-

Blue

AWG 6
Wire Size (mm2)
10.52-16.78
Max Current (A)
88
Notes
-

Yellow

AWG 4
Wire Size (mm2)
16.78-26.66
Max Current (A)
115
Notes
-

Red

AWG 2
Wire Size (mm2)
26.66-42.42
Max Current (A)
160
Notes
-

Blue

AWG 1/0
Wire Size (mm2)
42.42-60.57
Max Current (A)
215
Notes
Largest stable range retained in the main table.

Engineering-data note: the color ranges and maximum-current values above come from Electri Terminal factory selection data. Color is a product-family identifier rather than a universal ampacity standard; comparable manufacturer systems also map colors to particular wire ranges and tooling [8] [9]. Current capacity must be confirmed for the exact terminal, conductor, crimp, ambient temperature, and installation conditions [11].

Wire terminal color code and size selection guide

Section C

Stud Size Reference

Match stud diameter and terminal hole size to ensure stable fastening and contact consistency.

Stud and Hole Interpretation

Stud size indicates the bolt or screw diameter. Hole size indicates the opening needed on the terminal tongue. Keep clearance controlled to avoid loose fastening and vibration-related risk.

  • Use actual fastener size as primary constraint.
  • Avoid oversized hole clearance unless required by assembly tolerance.
  • Verify both wire-side and stud-side requirements in final selection.
Stud size and hole size chart

Mobile view: card layout for faster scanning.

#2

2.0 mm
Hole Size (mm)
2.2
Hole Size (inch)
.087

#3

2.5 mm
Hole Size (mm)
2.7
Hole Size (inch)
.106

#4

3.0 mm
Hole Size (mm)
3.2
Hole Size (inch)
.126

#6

3.5 mm
Hole Size (mm)
3.7
Hole Size (inch)
.146

#8

4.0 mm
Hole Size (mm)
4.3
Hole Size (inch)
.169

#10

5.0 mm
Hole Size (mm)
5.3
Hole Size (inch)
.209

1/4"

6.0 mm
Hole Size (mm)
6.4
Hole Size (inch)
.252

5/16"

8.0 mm
Hole Size (mm)
8.4
Hole Size (inch)
.331

3/8"

10.0 mm
Hole Size (mm)
10.5
Hole Size (inch)
.413

7/16"

11.0 mm
Hole Size (mm)
11.5
Hole Size (inch)
.453

1/2"

12.0 mm
Hole Size (mm)
13.0
Hole Size (inch)
.512

9/16"

14.0 mm
Hole Size (mm)
15.0
Hole Size (inch)
.591

5/8"

16.0 mm
Hole Size (mm)
17.0
Hole Size (inch)
.669

11/16"

18.0 mm
Hole Size (mm)
19.0
Hole Size (inch)
.748

3/4"

20.0 mm
Hole Size (mm)
21.0
Hole Size (inch)
.827

7/8"

22.0 mm
Hole Size (mm)
23.0
Hole Size (inch)
.906

15/16"

24.0 mm
Hole Size (mm)
25.0
Hole Size (inch)
.984

The listed stud-to-hole mappings are Electri Terminal product-fit references. ISO 273 defines general-purpose clearance-hole series for metric fasteners [7], while finished terminal dimensions still need to be checked against the selected item drawing. TE's published ring-terminal range is one comparable example of product-specific stud mapping [10].

Ring terminal stud size matching chart for different terminal types and screw sizes

Section D

AWG and mm2 Conversion Guide

Use these two reference charts to compare conductor cross-sections and convert between AWG and mm2 sizes during cable and terminal selection.

Cable Cross-Section Comparison

Visual overview of common cable diameters and cross-sectional differences for practical size comparison before final wire selection.

Cable wire diameter and cross-section comparison with size reference table

AWG to mm2 Conversion

Quick conversion chart for AWG and mm2 sizing, used to align US gauge notation with metric wire specifications.

AWG to mm2 wire size conversion chart
Use guide logic: first compare physical cable cross-section, then map to AWG/mm2 equivalent values, and finally validate current rating and application standards in your project specification. ASTM B258 defines nominal AWG dimensions and areas [5], while IEC 60228 defines metric conductor sizes and classes [6]. Treat AWG/mm2 entries as selection comparisons rather than exact interchangeable product sizes.

Sources & Engineering Basis

References

Standards support the general engineering method. Exact codes, dimensions, temperatures, colors, and reference currents remain manufacturer- or product-specific unless an individual certified datasheet states otherwise.

“Information on the materials and data from industrial experience is included.”

— IEC 60352-2:2024 scope summary [1]

  1. 1. IEC. IEC 60352-2:2024 — Crimped connections

    Standard

    General requirements, test methods, and practical guidance for uninsulated and pre-insulated crimped connections within the standard's stated conductor range.

  2. 2. UL Solutions. Connector Certification Services

    Certification guidance

    Applicable UL and IEC certification families for wire connectors, quick-connect terminals, and terminal blocks.

  3. 3. DIN Media. DIN 46234:1980-03 — Uninsulated ring terminal ends for copper conductors

    Standard

    Terminology and dimensional standard context for uninsulated ring terminal ends.

  4. 4. DIN Media. DIN 46237:1970-07 — Insulated crimp-type cable sockets for copper conductors

    Standard

    Standard context for insulated solderless crimp terminals for copper conductors.

  5. 5. ASTM International. ASTM B258-18(2026) — AWG nominal diameters and cross-sectional areas

    Standard

    Nominal diameters, cross-sectional areas, and calculation rules for solid round AWG conductor sizes.

  6. 6. IEC. IEC 60228:2023 — Conductors of insulated cables

    Standard

    Metric nominal conductor cross-sections and conductor classes; useful context when comparing metric and AWG designations.

  7. 7. ISO. ISO 273:1979 — Clearance holes for bolts and screws

    Standard

    General-purpose fine, medium, and coarse clearance-hole series for metric bolts and screws.

  8. 8. TE Connectivity. The Simple Guide to Crimping

    Manufacturer reference

    A comparable manufacturer system showing terminal color identification by wire range and matched crimp tooling.

  9. 9. ABB. Spec-Kon vinyl-insulated DIN ring terminals — technical data sheet

    Manufacturer reference

    A comparable vinyl-insulated terminal family rated to 75°C, with color coding tied to product wire-size ranges.

  10. 10. TE Connectivity. PIDG ring tongue terminals

    Manufacturer reference

    Comparable ring-terminal examples mapping AWG/mm² ranges, stud sizes, insulation support, and temperatures up to 105°C.

  11. 11. IEC. IEC 60287-3-1:2017 — Cable current-rating operating conditions

    Standard

    Why current-carrying capacity is conditional on operating and installation conditions rather than conductor size alone.

Last source review: July 23, 2026. Standards may require purchase for full text; links above point to the issuing organization's public record or to an original manufacturer document.

Quick Selection Logic

Choose by Terminal Form

Start with ring, spade, blade, pin, or disconnect form before checking other dimensions.

Confirm Insulation and Wire

Validate code, material, and wire-size interval from the stable range table.

Verify Stud Compatibility

Check stud size and required hole diameter to prevent mounting mismatch.

Selection FAQ

Read More: Selection Notes

How terminal model codes work
Model codes usually combine terminal form, insulation code, wire range, and mounting-related dimensions.
Why insulation code matters
Insulation code reflects material and crimp structure, which influences temperature rating and handling preference.
Why color coding improves speed
Color coding helps engineers quickly narrow applicable wire size ranges before checking full product specs.
Why stud matching is critical
Stud and hole mismatch can reduce fastening stability and increase contact risk during operation.