I have been tinkering these sets for a few years; I currently have three -002A's and two -003A's in my shop.
I have noticed what I believe is a design problem common to all of the machines, and I'm wondering if anybody has insight or has gone down this path before...
The main breaker seems to trip far to easily when hit with a starting surge (such as an electric motor). None of my -002's or -003's will start the hydraulic power packs on my car lift, ironworker, tubing bender, air compressor, etc. The main breaker just trips instantly. However, a little 5kW coleman generator that I have kicking around has no problems with these loads. The problem is a little less pronounced (but still exists) with 3 phase loads; the -002A will start my milling machine, but not my lathe. The -003A will start my lathe, but won't start a 10HP motor under no load (same issue...breaker trips before the motor even begins to move). These loads are well within the capacity of the generators...they work fine on smaller civvy units.
On the flip side, the 50A rating for the -002A and the 100A for the -003 is too high...it is possible to significantly overload the set with a more resistive load (such as a large welder, heater, or lighting). I believe than the main breakers should have a longer overcurrent delay, but a lower trip setpoint (30A breaker for the -002, and a 50A breaker for the -003).
I pulled the main breaker out of one of my parts sets just to see how it is put together...it has 6 main lugs (protecting the generator output), and 6 smaller lugs (appears to be protecting control circuitry inside of the generator). I couldn't find any other info on this breaker (model number) other than the manufacturer, but though a little web mining I believe that it is the Heinemann series AM-MIL.
So, on to my questions:
1. Is it possible that the starting surge is tripping the breaker because of the control circuitry? (Is the load's starting surge causing a corresponding surge in the field control circuit that is causing the breaker to trip?)
2. If #1 is true, I should be able to place a small resistor across the control circuitry terminals in increase this trip setting. Has anybody tried this? It wouldn't be a permanent solution, as it partially bypasses the breaker...but it may help determine what is causing the trip...
3. What does the R-3 adjustment procedure do? Is it in any way related to the control circuitry trip setting on the main breaker?
4. According to the schematic, it looks like the control circuitry trips the breaker through some kind of internal heater; does anybody know if these heaters are swappable (similar to the overloads on a motor controller)?
5. Can anybody see a disadvantage to separating out the main and control circuitry breakers? For example, if I just got a 3 pole 50 A thermal breaker for the main breaker, and small 1A pushbotton breakers (or fuses) for the control circuit, would there be any issue with this?