What's the full load current of the motor?
By Tristan Newton, Commercial Director · 22 March 2024 · 1 min read
Every electrical engineer has needed to find out the full load current of a motor at one time or another, often to check what to set the overloads at or to size the MCB/fuse on the supply.
If you've got access to the motor rating plate that will tell you, or there's various ways of estimating it with calculations. Neither of those is very convenient for us in the world of designing and manufacturing control panels. So we'll be let you into a company secret - we use a cheat sheet.
Disclaimer: you can't rely on these figures as they vary considerably from one motor manufacturer to another, so this really are just 'rule of thumb' figures.
For each motor size (shown in kW and HP) it gives the approximate full load current at 240V, 380V and 415V, and then also the suggested size for the MCB/fuses on the supply to it.
You're welcome. 😊
Written by the engineers at G&G Controls, a UK control panel manufacturer in Stoke-on-Trent. For general guidance only; consult a qualified professional for advice on your own installation.
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