---
title: "Table Helper"
description: "Pick a circuit's cable straight from the BS 7671:2026 Appendix 4 current-carrying capacity tables and the On-Site Guide maximum cable lengths, in Shine Forms and the Shine Forms tablet app."
source: "pirform"
---

# Table Helper

The Table Helper shows the BS 7671:2026 Appendix 4 current-carrying capacity tables for the circuit you are working on, so you can pick the cable from the table. It has:

- **Table 4D1A**: single-core 70 °C thermoplastic insulated cables, non-armoured.
- **Table 4D2A**: multicore cables, non-armoured.
- **Table 4D4A**: multicore armoured cables (SWA).
- **Table 4D5**: flat twin & earth.
- **OSG**: the On-Site Guide Table 7.1(ii) maximum cable lengths.

When you click **OK**, the wiring type, reference method, live and cpc sizes you picked are written back to the circuit.

![The Table Helper showing Table 4D1A for a single-phase circuit, with reference method C and 2.5 mm² chosen](https://www.shineforms.co.uk/docs/_img/table-helper.png)

## Opening it

In Shine Forms, open the certificate and go to the **Circuits and Test Results** page. Select the circuit, then click **Table Helper** in the **Circuits** group of the ribbon. It opens for the current circuit in the schedule. The button is there on certificates with a circuit schedule, the EICR and the EIC.

In the tablet app, tap the circuit's **Wiring type** or **Reference method** and tap the Table Helper link at the bottom of the picker. It works on the EICR, EIC and Minor Works 2026. The picker only appears when **Show single letter wiring types and reference methods** is turned on in the app's Options. See [Circuits and test results](https://www.shineforms.co.uk/docs/tablet-app-circuits-and-tests#wiring-type-and-reference-method).

## The window

- **The header** shows the board and circuit, and the circuit's phase, **Single-phase** or **Three-phase**, with the **Show other phase** tick box.
- **On the left** is the **Wiring type** drop-down, with a hint under it for some wiring types, and the **Tables** list. Tables that don't apply to the wiring type are greyed and marked *not for this wiring type*. A note at the bottom says how columns for the other phase are shown.
- **In the middle** is the table: its title and details, then the table as it is printed in BS 7671, with its grouped column headings (Reference Method A, B, C and so on, with their conditions and the columns under them). Long headings wrap onto two lines to keep the columns narrow.
- **The footer** shows what you have chosen: **Wiring type**, **Reference method**, **Live**, **CPC** and **Capacity**, with the table the capacity came from. **OK** and **Cancel** are at the right.

## Choosing the cable

- Click a **column heading** to choose the reference method.
- Click a **size** (the round button at the start of a row) to choose the live conductor size.
- Click a **cell** to choose both at once.

Click **OK** to write the wiring type, reference method, live and cpc to the circuit. **Cancel** changes nothing.

### Columns for the other phase

Columns for the other phase, such as the three-phase columns on a single-phase circuit, are dimmed and can't be picked. Untick **Show other phase** to hide them. This makes the table narrower. Shine Forms remembers your choice next time, whether you closed the window with **OK** or **Cancel**.

![Table 4D1A with Show other phase unticked, so only the single-phase columns are shown](https://www.shineforms.co.uk/docs/_img/table-helper-other-phase-hidden.png)

If a table has no columns for the circuit's phase, its columns stay shown, dimmed. Table 4D5 on a three-phase circuit is an example.

### Variants of a code

Some wiring types and reference methods are stored as a variant of the BS 7671 letter, for example reference method **CM** (multicore) rather than **C** (single-core). The footer then shows the letter with the stored code under it, such as **C** *stored CM*.

![Table 4D2A for multicore cable, with the footer showing reference method C stored as CM](https://www.shineforms.co.uk/docs/_img/table-helper-4d2a-multicore.png)

### Flat twin & earth

Selecting from Table 4D5 stores wiring type **AF** (flat twin & earth). The window says so under the table.

![Table 4D5 for flat twin and earth, with the note that selecting from 4D5 stores wiring type AF](https://www.shineforms.co.uk/docs/_img/table-helper-4d5-flat-twin-and-earth.png)

### The OSG tab

**OSG** shows the On-Site Guide Table 7.1(ii) maximum cable lengths for the circuit, by protective device and cable size, with the installation methods each row allows.

![The OSG tab showing maximum cable lengths for ring final circuits](https://www.shineforms.co.uk/docs/_img/table-helper-osg.png)

## Wiring types with no table

If you choose a wiring type that no Appendix 4 table covers, such as **H** (mineral insulated), every table is greyed and a warning explains that nothing will be rated.

![The Table Helper with wiring type H chosen, every table greyed and a warning shown](https://www.shineforms.co.uk/docs/_img/table-helper-no-table.png)

## On the tablet

The tablet app shows the same window, sized for the tablet.

![The Table Helper in the tablet app showing Table 4D1A](https://www.shineforms.co.uk/docs/_img/table-helper-tablet.png)