... is optional 8) 230 / 400V AC, 50Hz , 0.8pF three-phase and four wires alternating current output9) Frequency: <3%10) Frequency ... load and over current b) Operation display: i) Unit voltage, tri-phase load current and frequency display ii) Water temperature, oil pressure ... tank cooling system e) Flange connector f) 12 / 24V starting motor and charge engine g) Air cleaner, fuel cleaner, oil cleaner ...