To resistor or not to resistor...

[SpeedVision]

I recently purchased the following power supply to power my FMA Cellpro charger:

Eagle Vortec 700W ATX 12V V2.2/EPS 12V V2.1 UL & FCC Power supply for ATX cases... (phew)

I have been following most of the conversion methods and determined that the power supply does everything I need without adding a resistor. I simply followed one of the treads about grounding the green wire and using the 2 yellow and 2 black wires for the P4 connector to get my 12V supply. I am getting 12.05 volts with no load and 12.00 volts while charging. Great, no problem there!

Question is coming... I read that you "could" damage the power supply (maybe over time) if you have it ON with no load... Since there are soooo many different types in existence, what is the consensus about NOT using a resistor to create a load when no other load is present - on a brand new "state of the art" power supply???

Thank you for your replies!

-Michael

btw - Someone posted a tip about this unit selling for 95 bucks with a 95 buck rebate - total cost was 11.51 shipping. Special thanks to the individual that gave us the head's up. This think is the sexiest power supply I've ever seen... :D

[tomahawkflier]

Turn it off when your not using it.

[SpeedVision]

Turn it off when your not using it.

Ahhhh, thanks... :p

Since newer generation power supplies don't "reqire" a resistor to provide stable 12V supply (for at least 1 charger, haven't tested at higher draw), as referenced in this mutch discussed post - http://www.rcgroups.com/forums/showthread.php?t=368639 , I was hoping to explore any possible negative effects of not having a continuous draw on the power supply and any possible long term effects (premature failure). While the power switch is a handy tool, it's just a band-aid relative to the big picture.

Since newer PS Power supplies will work their way into the "norm", it wouldn't be bad to try and call this out early and save everyone the grief of having to retool too soon. In my case, I got a 100 buck powersupply for almost nothing. I'd like to insure many years of trouble free service. Thanks.

[darkith]

I had a used AT power supply which regulated just fine without a resistor, but after a few measly months it started getting flakey to the point where it wouldn't fire up when powered on, but required a few power cycles to start. After a while, it died completely.

It might not have been related to the lack of a stabilizing resistor, but I figure it's cheap enough to put the resistor on...

D.

[SpeedVision]

Well, I ended up mounting a 10 watt 10 ohm resistor to one of the 5 volt taps. This power supply has 2 fans, so I mounted the resistor externally, directly in front of an air intake and it doesn't get over 130 degrees F. Bosted the voltage from 12.09 to 12.30, but raising the voltage wasn't a requirement. Peace of mind I guess.

Who knows if the thing will last for years or erode into a slow power supply death.

I still think the latest power supplies will be more susceptible to developing problems with the low power requirements placed on them by a small 4 amp or less charger... Of course, I have no experience to base my assumption... I was hoping for more discussion. Oh well. I guess it is the self-preservationist in me.

[tomahawkflier]

I've done something similiar with my power supply though I thought the resistor load on the 5 volt line was to get it to deliver the full amount of amps, Not voltage.

I drilled one of the ally heatsinks, Got a big sandbar resistor, Applied thermal grease and used cable ties to attatch the resistor to the heatsink. Never had any worries and it outputs a measured 15 amps as the box says it should.