Power supplies with inductive load surge current outputs

Thread Starter


Joined Oct 21, 2016
Hi all,

First time poster. Firstly I am an electrician by trade and I am currently at university doing electrical engineering but I am by no means an expert in electronics hence why I have come here.

I know basic power supply design and have made very simple ones before mainly for my own uses they were just 230V a.c input / 24V 2A d.c output. However, I am starting to use heavy duty solenoid locks that have inductive loads. They are rated as 2A continuous but as with inductive loads the surge current in the first few seconds can be up to 14A. How do power supplies accommodate these high current surges? any examples would be great also.


Joined Mar 14, 2008
Are these AC or DC solenoids?
I don't see how a DC solenoid can have a surge current greater than its rated current but an AC one can.


Joined Jun 4, 2014
If they are DC powered and if you have a switch between the power supply and the solenoid then put a diode in parallel with the solenoid to trap the back-emf when switching off.