Do chargers have higher current draw upon plugging in?

markz

100 TW
Joined
Jan 9, 2014
Messages
12,179
Location
Canada and the USA
I was thinking due to the coils and transformer that it may require extra amps the instant you plug the charger in, with nothing being charged. I hope thats the case, but I have my doubts and I have to keep troubleshooting.

Reason I ask is because I have replaced 3 fuses, on 3 different mw's.

Now the fuses I used are 250V and 5A, but the ones MW uses are 250V 6.3A and my store did not have anything higher then 5A in through hole.

Here are the fuses I bought. First thing the ac line sees coming in is this fuse plus a capacitor to the other ac line.
BUSS FAST ACTING FUSE RADIAL 5A 250VAC SR5F-5A-BK SR-5F-5A-BK PCB/THRU-HOLE STYLE (5.08MM)
https://www.be-electronics.com/product_p/sr5f-5a-bk.htm

MW's are F6.3A /250V CQ MSF
MSF is the series, CQ is the company name Conquer Electronics
http://www.anglia-live.com/netalogue/pdfs/cqr/datasheets/MSF%20Data.pdf
BTW Conquer's website states Anglia is an authorized partner. http://www.conquer.com.tw/

I found these, they match, closely. Plus s/h is decent with mouser.
https://www.mouser.ca/Circuit-Protection/Fuses/_/N-ba85y?P=1z0x8dpZ1yy2lkn

I hope the issue is 5A and I dont have to hunt down a related broken component.
I hope

See my adventures here
https://endless-sphere.com/forums/viewtopic.php?f=14&t=96731#p1417342
 
I can't offer much insight into the workings of your charger but it's very, very unlikely you're blowing the fuse on plugin just because it's 5 amps instead of 6.3.
 
flat tire said:
I can't offer much insight into the workings of your charger but it's very, very unlikely you're blowing the fuse on plugin just because it's 5 amps instead of 6.3.

You are most likely right.
I thought I'd ask.
tyvm

edit
This is what I was thinking when I posted this question but I found the items that do take a lot of amps upon plugging are the inductive motors. The coils and transformers don't.
 
Maybe you might want slow blow fuses? The fast blows are meant to protect really sensitive equipment, where a Meanwell is just sort of filling itself up with electricity on plug in but then stops...
 
Here is an interesting find

https://www.ebay.ca/itm/400W-36V-11A-Single-Output-Switching-power-supply-AC-to-DC-SMPS/251929195856?hash=item3aa8267550:g:Du0AAOSwQiRUl8GX:rk:16:pf:0

inrush current.jpg
 
When you first plug in any kind of switching power supply, the AC line goes through a bridge rectifier and charges a big capacitor which is starting out at zero volts. There is a big current spike, but it is so fast the fuse doesn't have time to heat up and blow (normally). Once the main cap is charged, the current drops to normal.
 
Some chargers have an ICL (inrush current limiter) to minimize the load on the AC end of things, including the caps.

Some threads referencing "inrush" in the first post; not all are relevant but may help:
https://endless-sphere.com/forums/search.php?keywords=inrush&terms=all&author=&sc=1&sf=firstpost&sr=topics&sk=t&sd=d&st=0&ch=300&t=0&submit=Search

Just stuff related to charging:
https://endless-sphere.com/forums/search.php?st=0&sk=t&sd=d&sr=topics&keywords=inrush+charger*&sf=firstpost

Slow blow fuses shouldn't blow under an inrush current, though it's possible fast blow ones would, if rated too low. They may actually have used 6.5A fuses (if fast blow) just so they wouldn't pop under inrush, but would still blow in the event of a failure. If this is the case, a 5A fast blow may not work.


However, *something* caused the original fuse to blow. If you don't know what that is, then the reason the fuses are popping could be a failure or defect in the charger, including a leaky cap.

If they're not genuine MW, then they could have any number of parts, including caps, that are also not "genuine", or are simply crappy cheap parts, and could be the cause of the problem.
 
Thanks for the input.

They are all genuine mw's

I have ordered some parts, including rectifier diodes, the correct fuses, a big diode and a handful of other parts just in case.

There are 3 different defective issues with my set of 5 mw's.

Going forward as I casually trouble shoot these mw's is one option which fechter mentioned in my other post about my mw's, is to power up a mw and trace the ac input line, and check out the rectifier diode.

Moved onto other projects to get charging again so I can ride again.
 
If you look up Dnmun's charger troubleshooting threads, he gives various methods of testing SMPS's, and what to test, that may apply to yours. One of the most helpful is using an incandescent lamp in series with the AC input to help limit inrush current.
 
Back
Top