The IET is carrying out some important updates between 17-30 April and all of our websites will be view only. For more information, read this Announcement

Rules and Guidelines
Want to participate in the discussions? Please read our Community Rules and Guidelines. Need some help? Visit Support and Answers.

  • State Not Answered
  • Locked Locked
  • Replies 13 replies
  • Subscribers 13 subscribers
  • Views 5753 views
  • Users 0 members are here
Options
You may also be interested in
This discussion is locked.
You cannot post a reply to this discussion. If you have a question start a new discussion

Maximum current for a unit supplied from a 13A socket, taking supply voltages into account.

Anthony Hoare
I am currently developing a heated food merchandising unit to be supplied from a 13A three pin plug.


If the unit is designed around 230V, 13A,  do I have an issue when the supply voltage is at the top of its tolerance (230V + 10% = 257V).

As I have a purely resistive load, the current drawn would be 14.3A

Is this an accepted method or should the unit be designed around 257V 13A?


Your help would be appreciated.


Tony Hoare
Parents
  • 0
    I wouldn't push a BS1362 carttridge fuse beyond 13A for moe than a few minutes. Running at 'full power' for 45 Minutes will cause it to blow I suspect.

    Although I have never known the Uo in the UK to be higher than 247V and and absolute maximum of 253V at +10%.


    If the rated load is 3kW at 230V (13.04A) then it will be 3.3kW at 253V which equates to 13.66A that doesn't take into the rise in temperature due to the heated element and extra current

    IMO, I would keep the supply lead to 2m and because you're likely to be running the load 'flat out' use a good quality extention lead if at all necessary.
Reply
  • 0
    I wouldn't push a BS1362 carttridge fuse beyond 13A for moe than a few minutes. Running at 'full power' for 45 Minutes will cause it to blow I suspect.

    Although I have never known the Uo in the UK to be higher than 247V and and absolute maximum of 253V at +10%.


    If the rated load is 3kW at 230V (13.04A) then it will be 3.3kW at 253V which equates to 13.66A that doesn't take into the rise in temperature due to the heated element and extra current

    IMO, I would keep the supply lead to 2m and because you're likely to be running the load 'flat out' use a good quality extention lead if at all necessary.
Children
No Data

Join us to get the best from IET EngX.

Joining EngX lets you personalise your experience so you stay up to date on the topics that interest you, plus you’ll be able to make connections who are looking to collaborate, exchange ideas and more.

Join us Not now

Community Rules & Guidelines