You are correct with regards to the limited differences between units... I have documented them all on paper and am transposing them over to a simpler format for posting... additionally I have documented the PCB schematics for the current control circuit and voltage control / range portion.
That said... I've tried replacing the 280 ohm with a 250 ohm variable pot and had poor results with stability of output current and also voltage...
Once I have this finished up (tonight I hope, working on it now) I will be posting instructions for testing and then modification of voltage and current along with calculations to be done for proper voltage / current. There are a few other adjustments I will be suggesting also to enhance the safety and stability of these supplies.... if you can wait a short while, your chances of success should approach 98% with a good MTBF.
The other thing that has been holding me back is the lack of a decent scope, Fechter has one on hand (4 channel, lucky bugger) and now he has a 24v S-350-R17VAI to work with (he has been helping blindly for weeks).... there is only so much I can do with all the test points and monitoring of voltage but I am limited to a 10khz sample rate at best (not even close to a scope) so I can't really test the PWM on the scope to vary it properly.
BTW: on the 201 series, R37 is populated and decreasing it's value will lower the current... on our R18VAI and R17VAI units ( I have both, seems 24v is R18 and 48 is R17VAI) this resistor is not populated but it's location is there to form a fully variable (1-7A) adjustment... there is a transistor, diode and pot that aren't populated either which feedback into the TL494 error amp. Your units don't have this variable feedback with overshoot protection.
Although I am not finished testing (but working ferverently, even with my bank of headlights for rapid discharge @ 10-20A it still takes a while to cycle these test packs) I am including logging from the first charging tests I performed after my current mods... before this I was seeing peaks of 8.5-9A... this is much better...
A note, the peaks I mentioned earlier... I have figured them out, when the fan circuit engages it consumes too much current which causes the internal isloated logic voltage bus to drop and therefore causes the voltage presented to the ERROR AMP inputs, the DEAD TIME CONTROL or both to fluctuate (one is negative biased, one positive)... this in turn causes the supply to produce a higher PWM and as such more current, ie the spikes - I am working on this issue now...
Meanwell S-350-48 (v S-350-R17) - Voltage output modified for 63.8v maximum, set to 62.25 (ish) and current modified by replacing my R33 with 2x 100ohm (Radio Shack) resistors in series.
3x5S Turnigy Lipo 5000mah 20/30C in series for 15S1P or 15S 5AH... pack starting voltage was approx 55.8v and initial (intentional) inbalance was 30mv +- 4mv (resolution accuracy but measured on a cell by cell basis).
Eagle tree has Meanwell as Batt and Batts as ESC to properly track positive AMPS and MAH accumulated. Connected to PC and running the EagleTree software in Live Mode. Also monitored the Power Supply Temps.
For those interested, here is the full EagleTree log file for your viewing pleasure: http://www.e-bikemike.com/reviews/Meanwell%20S-350-48/monitored_charge_1/EagleTreeLog_MonitoredCharge_1_15S1P_1C_Meanwell-S-350-48_62.25.zip
Without further delay... some pics(since Pics rule the world in ES).
Amps and Volts over Time - The peaks are from fan switching on, note the peaks in voltage correspond with the peaks in current... this means either both of the regulation circuits (Current and Voltage) or the DTC (which sets maximum duty cycle) MUST be seeing issue from this voltage drop.
Amps volts and watts over time (for those who don't want to do the math):
Since warm to the touch isn't accurate enough - here Amperage, Wattage and Temperature of the Meanwell over the charge process:
Configuration prior to connection of load (batteries):
These two screen shots are first few seconds (milliseconds?) after connecting the pack (load) and show the ramp up to current output... I have also been addressing this as I would prefer a slower current ramp up than this... (so I am playing with adding a ramp delay to startup):
First Sample grabbed on connect:
Stabilized after connect:
The final result: