Electronics > Beginners
Correcting AC line sag - Is this do-able?
(1/2) > >>
Cliff Matthews:
I have 2 beefy 500VA transformers I'd like to pair-up with 2 100VA units as shown (see pic*).
Q: Can over-all current draw boost the smaller transformer and cancel-out good portion of output line sag?

*I have a large variety of the toroid chokes (some up to 64oz.)
T3sl4co1l:
Nope!  Draw out the node equations if you can.  It looks right if you consider just current going forward, but transformers are reciprocal devices, i.e., the same thing happens in both directions.  So you need to consider the current going backwards, and the voltage as well. :-+

Tim
Cliff Matthews:
Ha! I guess you knew I'd finally get around to either using or chucking that stash. I'll digest that more before they get trashed (god I hate throwing stuff out.. >:( )
IanB:
If you have a transformer with a low voltage secondary you can always use it as an auto-transformer to boost the line voltage...
Cliff Matthews:

--- Quote from: IanB on March 31, 2019, 01:30:36 am ---If you have a transformer with a low voltage secondary you can always use it as an auto-transformer to boost the line voltage...

--- End quote ---
What I was looking for was some linear correction.. :-//

As my semi retired brain understands it, transformer output voltages are rated at full load and typical output regulation from no load to full is -10%. In this configuration, I have little problem with raising the input voltage on the 100VA unit to reduce total output sag to -6% before the fuse blows. It's really just a cheap novice attempt to get a 600VA isolation rig to act a bit more like 1000VA rig with the mountain of toroids I have hanging around.

In mains distribution, I've heard they regulate sag sometimes with commutator taps (now that's beyond me..)
Navigation
Message Index
Next page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod