dcb;553098 wrote: It will tell you the volts/amps/temp? and all you do is tell it what to do next?
I'm quite rusty on the slave firmware. I think by default it doesn't put any info on the serial port, as Paul stated, but it's easy (if you are modifying firmware anyway) to make it emit the same data that a master does. Usually this makes no sense, as the master is already outputting this info. So this would be only for "stand alone slave" firmware.
1. is the slave firmware model specific. i.e. pfc-1500, pfc-2500, etc.
I had a quick look, and the first one I looked at had a lot of voltage/current/power specific code in it. But that was for if the EEPROM doesn't have an expected value, but that value is there for every charger we've ever examined. So that part is never called.
But it's probably like the master code; they could have written it to be completely model independent (reading anything model specific from the EEPROM values), but they haven't. In our "canonical" firmware (just one of the Lithium-based ones that looked recent), we've been modifying it to be model independent. We think we've achieved that, or maybe there are one or two places left that aren't quite independent. But it works well enough to run a 96 V nominal charger (originally a 144 V nominal, from memory).
2. with a microcontroller master, can it manage the calibration instead of eprom fun?
No, the masters don't have any capability for calibration. The normal charger software uses about 7.7 kiB of the 8 kiB flash memory, so there is no room for anything special.
3. each model has specific voltage/amp ratings, I am thinking there are different components involved, but by any chance are they universal?
Most of the charger components are model independent. The things that affect the output voltage and current are
1) The high voltage transformer. It usually has something like "144 V 14:8" written on it, meaning 144 V nominal (some 190 V max), and a turns ratio of 14:8. So it outputs some 8/14ths of the voltage at the output of the PFC stage. If you work on 330 V at the DC bus, multiplying by the turns ratio (8/14) will get you close to the max voltage. For this ratio, 330 x 8/14 = 189 V. Of course, as the ratio increases (more voltage), the current decreases.
2) The MOSFETs may change, though we've often found the same or similar ones in widely different voltage models.
3) The output rectifiers may change. In particular, the very high voltage models (say 300+ volts) have two output windings, each with their own rectifiers, which are put in series. I believe that this is because it's difficult to get fast rectifiers that handle high voltage. For example, I've seen "300 V 13:8:8" written on a transformer. This one puts out 417 V maximum. So it's really a 13:16 transformer (step up, not step down), with the secondary split into two windings.
4) The 1500 W and 2000+W models are similar too. In the larger models, the 12 V transformer may be bigger, the PFC inductor
is larger and is placed horizontally, and there are three capacitors instead of two in the PFC area. The back ends are much the same, possibly identical. Of course, due to the larger current capability for a given voltage, the current-reading shunt
(R20) will have a different resistance.
Edit 2016/Mar:
Actually, the PFC inductor looks superficially to be the same size on 1.5 kW and 2.0 kW models, just horizontal and heat sunk on the 2.0 kW models.
5) The top ends of the voltage dividers (R20 and R10) are model-voltage dependent, and are calibrated in EEPROM. The DC side rectifiers (D1/D4/D5/D6) can vary with model-current. The snubber resistors (R33 and R4) have been observed to vary between models.
The capacitance and voltage rating of the three electrolytic capacitors on the DC side (near the output relay) are model-voltage dependent. The large inductor on the DC side (near these three capacitors) seems to have varying number of turns, and may have different core composition. It is marked with the power and nominal voltage of the charger, indicating that it probably changes with these parameters. There may be other differences.
i.e. can a 48v charger make 240v (assuming you limit the current) with slave firmware?
This would require a "transformer transplant". Someone has tried this, and I can't remember what the result was. I think it worked. [ Edit: that would be Vectrix150V in
this post. Thanks for chiming in, Vectrix150V. ]
Once the hardware is modified for the different voltage/current, it would not matter if it's a master or slave or CAN version (assuming that you change the firmware to suit, of course). If it's a slave or CAN model, there is a slim chance that you could get away with keeping the original firmware. The problem is how they haven't strictly used the EEPROM data everywhere. You'd think it would be in their interest to keep the number of firmwares down, but they seem to treat nearly every customer as a unique build. All the "curves" are in the master firmware, so that makes almost every firmware unique to start with.
4. how does one obtain said firmware (and details on slave control)?
You either wait patiently for me to post it (coming soon!), or if you are in a hurry, PM one of us (Coulomb, PDove, or KennyBobby). We don't intend to sit on this; it's just I've been busy on other things lately.