Well... I have noticed that there are some RS-35M's out there that are "heavier-duty" than others. I have one with a heavier heatsink, larger xfmr, stud-type SCR, and an extra filter cap. I guess they must have started making them cheaper since...
I am running a 40 Amp charge controller. Therefore, I believe I need a PS that will run cool and current limit at 35 or 40 Amps so I can get out of current limiting faster when recovering from a state of discharge after an AC power failure. Which model(s) would that fit? (Time to go search the web...) Steve AA5SG ----- Original Message ----- From: "Steve Rodgers" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Sunday, September 26, 2004 10:39 PM Subject: Re: [Repeater-Builder] BIG battery & Astron current limit > One thinkng I forgot to mention: Batteries should be charged from a current > source. What this means is the maximum charge current should be limited to > protect the power supply. I would call Astron and ask them how to modify the > RM35M so it starts folding back at 15A instead of its default of 35A. Your > power supply will thank you for it. > > Steve > WA6ZFT > > On Sunday 26 September 2004 20:20, Steve Rodgers wrote: > > The question should be how long before the Astron RS-35M burns up running > > at 34A? The power supply is rated for 25A continuous duty, 35A intermittent > > duty. I don't like running mine north of 15A continuous without a fan. > > This is the weakness with the Astron supplies. If you load them up to rated > > output they run very hot. If you are planning on running 35A continuous, > > I'd get an RM-60 or an RS-70. > > > > Steve > > WA6ZFT > > > > On Sunday 26 September 2004 20:01, Steve Grantham wrote: > > > How long would the RS-35M run in current limit at 34 Amps? (This is > > > about 97%.) > > > > > > I have noticed that the internal ammeter sometimes lacks good > > > calibration. As measured on a quality manufactured shunt, 34 Amps pegs > > > out the panel ammeter on the RS-35M, which indicates 40 Amps Max. > > > > > > Anyone have experience with this? > > > > > > Steve > > > AA5SG > > > > > > > > > ------------------------------------------------------------------------- > > >-- ----- > > > > > > The below quoted from: > > > http://www.repeater-builder.com/astron/astron-rsbattmod.html A couple of > > > additional comments presented by Joe Montierth .... > > > One, the 10K resistor can be 1/4 watt or even 1/8 watt, the 1/2 watt is > > > overkill. There is not much voltage across it to generate any heat. > > > > > > Two, depending on the size battery it is attached to, you might want to > > > reduce the current limit point on the Astron. The 35 amp Astron will > > > current limit somewhat above the 35 amp point, maybe around 37-39 amps. > > > If you have it attached to a BIG battery, it can run several hours at the > > > current limit, and burn itself out. If you parallel R4 with a 1K pot, you > > > can adjust the current limit to a point less than 38 amps, usually about > > > 70-80% of the power supply rating is good. > > > > > > Three, always turn the PS "on" before attaching it to the battery. This > > > will keep the internal caps charged up, so they don't have to suddenly > > > charge through the pass transistors on the Astron. > > > > Yahoo! Groups Links > > > > > > > > > > > > Yahoo! Groups Links > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
