The alternator with Shunt excitation is self excited with an R 230 voltage regulator.  The regulator monitors the  exciter excitation current as a function of the alternator output voltage. Very simple in design, the alternator with shunt excitation has no sustaining short-circuit capacity.
- Voltage regulation: around ± 0.5%
- Voltage supply/sensing range 85 to 139 V (50/60 Hz)
- Rapid response time (500 ms) for a transient voltage variation amplitude of ± 20%
- Voltage setting P1
- Stability setting P2
- Power supply protected by 8 A fuse, slow-blow action (tolerates 10 A or 10 s)
-Frequency: 50 Hz with ST3 jumper - 60 Hz without ST3 jumper
- Factory set under speed protection