The Weld Fab Welding & Fabrication Planning Desk
Menu

SHEET TWF·T-05 REV 2026-08-20 METHOD M.2026-08-20.1

Duty-cycle planner

Converts the nameplate duty-cycle percentage and reference window you enter into operating and rest minutes at that same current — it never extrapolates the rating to any other setting.

Classification Same-current schedule from entered rating

InputsT-05
F-01 Nameplate
%

Over 0 and at most 100, from the nameplate or manufacturer data.

F-02
min

The window the rating is stated over — 10 minutes in the worked example.

F-03

Optional label copied onto the record — the schedule stays valid only at this rating.

JavaScript is off in this browser, so no live record can be issued. The worked example below walks the full method with real figures, and the blank card on this page prints as a worksheet.

R-DUTY-nnn

Duty-cycle planner

Awaiting inputs — enter values and issue a record. Empty slots below print as a blank worksheet.

Field slots

F-01Nameplate duty cycle
F-02Reference window
F-03Current / setting (record only)
RECORD VOID — inputs changed since issue. Recalculate to issue a new record.

Worksheet · https://theweldfab.com/tools/welding-duty-cycle-planner/ · METHOD M.2026-08-20.1 · REV 2026-08-20

Worked example

STATIC — not a live result

A 60% nameplate duty cycle in a 10-minute reference window: 6 minutes operating and 4 minutes resting per window, valid only at the current the rating was stated for — 180 A on the example nameplate.

R-DUTY-EX

Duty-cycle planner

Planning estimate

6 min operating / 4 min resting per window

Entered assumptions

F-01Nameplate duty cycle60 %
F-02Reference window10 min
F-03Current / setting (record only)180 A (example nameplate rating)

Planning figures

R-01Operating time per window6 min
R-02Rest time per window4 min

Planning support only — verify against nameplate/manufacturer data.

RECORD VOID — inputs changed since issue. Recalculate to issue a new record.

Method

M.2026-08-20.1

Two lines of arithmetic on the entered rating, inside the reference window the manufacturer stated it over:

  • operating minutes = window minutes × duty % ÷ 100
  • rest minutes = window minutes − operating minutes

Worked figures: 60% in a 10-minute reference window gives 6 minutes operating and 4 minutes resting per window. The current or setting label is copied onto the record untouched, so the schedule stays pinned to the rating it came from.

Limits & stop conditions

T-05
  • The schedule applies only at the current or setting the rating was stated for — duty cycle does not extrapolate, and this planner will not do it.
  • A different current needs the manufacturer’s duty-cycle curve or a rating stated for that current.
  • HOLD — a duty cycle outside 0 to 100% or a reference window of 0 minutes or less keeps the record unissued.

Source register

  1. S1 Metal Inert Gas (MIG) Welding — Process and Applications (Job Knowledge 4) ↗ TWI Ltd retrieved 2026-08-19
Bench Awaiting values