# Radial PTC fuse

Bel Fuse's 0ZRE series of radial-leaded polymer PTC resettable fuses. Each is an epoxy-coated body on two straight leads fixed to its two faces. The body is either a round disc (the sheet's Fig. 1 and 4) or a rectangular block (Fig. 2 and 3).

The body is centred on the Z axis, with its faces normal to Y. Lead 1 is at -X and +Y, and lead 2 at +X and -Y. The leads are C apart along X and F apart along Y. The board's top face is the XY plane, at the foot of the coating, and the leads go straight down through it for `tail`. The body and each lead are their own solids.

## Source

Bel Fuse Inc., "Type 0ZRE Series", Rev. 0ZRE Apr2023, <https://www.belfuse.com/media/datasheets/products/circuit-protection/ds-cp-0zre-series.pdf>. The table is from page 3, "Product Dimensions" (all dimensions in mm). The hold currents are from page 1, "Electrical Characteristics".

| Part number | Hold (A) | Fig. | A width max | B height max | C lead spacing typ. | D lead length min | E thickness max | F lead offset typ. |
|---|---|---|---|---|---|---|---|---|
| 0ZRE0005FF | 0.05 | 1 | 8.3 | 10.7 | 5.1 | 7.6 | 3.8 | 1.6 |
| 0ZRE0008FF | 0.08 | 1 | 8.3 | 10.7 | 5.1 | 7.6 | 3.8 | 1.6 |
| 0ZRE0012FF | 0.12 | 1 | 8.3 | 10.7 | 5.1 | 7.6 | 3.8 | 1.6 |
| 0ZRE0016FF | 0.16 | 1 | 9.9 | 12.5 | 5.1 | 7.6 | 3.8 | 1.6 |
| 0ZRE0025FF | 0.25 | 2 | 9.6 | 17.4 | 5.1 | 7.6 | 3.8 | 1.8 |
| 0ZRE0033FF | 0.33 | 2 | 11.4 | 16.5 | 5.1 | 7.6 | 3.8 | 1.8 |
| 0ZRE0040FF | 0.40 | 2 | 11.5 | 19.5 | 5.1 | 7.6 | 3.8 | 1.8 |
| 0ZRE0055FF | 0.55 | 3 | 14.0 | 21.7 | 5.1 | 7.6 | 4.1 | 1.9 |
| 0ZRE0075FF | 0.75 | 3 | 11.5 | 23.4 | 5.1 | 7.6 | 4.8 | 1.9 |
| 0ZRE0100FF | 1.00 | 4 | 18.7 | 24.4 | 10.2 | 7.6 | 5.1 | 1.9 |
| 0ZRE0125FF | 1.25 | 4 | 21.2 | 27.4 | 10.2 | 7.6 | 5.3 | 1.9 |
| 0ZRE0150FF | 1.50 | 4 | 23.4 | 30.9 | 10.2 | 7.6 | 5.3 | 1.9 |
| 0ZRE0200FF | 2.00 | 3 | 24.9 | 33.8 | 10.2 | 7.6 | 6.1 | 1.9 |

The same page gives the lead size by figure: Fig. 1 is 24 AWG, Ø 0.51. Fig. 2 is 22 AWG, Ø 0.65. Fig. 3 and 4 are 20 AWG, Ø 0.81. The figures draw B from the body's top down to where the leads leave the coating, and D below that. The model uses the maximum A, B and E and the typical C and F. The packaging suffix (1C, 1E, 1A, 2A and so on) doesn't change the part.

**Proportions, stated plainly.** The figures draw these but don't dimension them:

- A round body is a disc A across, with its top at B. Below the disc, the coating runs down each lead to the board as a sleeve 2.5 times the lead's diameter.
- A rectangular body is a block A wide and B high from the board. Its top corners are rounded with a radius of 0.15 times A.
- The leads are straight. The figures' kinks where the leads leave the coating aren't modelled.

**Materials.** Page 3 gives "Insulating coating: Flame retardant epoxy" and "Lead material: Matte tin plated copper", and no weight, so the mass isn't checked. The body is a carbon-filled polymer between two metal plates under the epoxy coat. It is shown as pmma (1.18; epoxy is about 1.2), in a colour for looks. The leads are copper.

## Catalogue models

The old catalogue's 13 `Fuse_BelFuse_0ZRE_*` entries have no reference models. Each names an exact Bel Fuse part number, with the sheet's A and E as its L and W (for example `0ZRE0005FF_L8.3mm_W3.8mm`), and each maps to the preset of that number.

The family's chip fuses and fuse holders are left with their reasons in `COVERAGE.md`.