Fuses; Protection Fuse; Fuse For The Internal Power Suplly; Trimpots Function - WEG WRGA-02 Manual De Instalación, Operación Y Mantenimiento

8. FUSES

8.1 PROTECTION FUSE

The F1 (WRGA-02) fuse and the F1A and F1B (WRGA-02 /D) fuses are used to limit the power supply input current with the
purpose of protecting the generator field.
The F1 WRGA-02 possesses a rectifier that controls the field voltage of the generator. For the highest field voltage, the power
supply input current is half the field current, which means that the maximum current of the fuse has to be a little more than half
of the current supplied by the regulator.
The WRGA-02/D regulator possesses a complete bridge three phase rectifier with a ratio of 1.35 for continuous field voltage vs
the efficient power supply voltage and with a input current 1.35 times the field current. For this case, a fuse with the same rating
as the field current is used. Below are listed some of the characteristics.
Recommended manufacturer: LittelFuse (ordering code: 235003)
Characteristics: Fast acting fuse.
Dimensions: 5x20 mm.
Current / Voltage: 5A/250V.
Opening time:
Table 2 - Fuse opening time.
% of maximum current

8.2 FUSE FOR THE INTERNAL POWER SUPLLY

The fuse F2 for internal power supply protection is intended to protect only the auxiliary power supply of the circuit which does
not have high energy consumption. This fuse must be for 1,25A/250V.

9. TRIMPOTS FUNCTION

Vad: Voltage adjustment.
Stb: Stability adjustment.
U/F: U/F limiter (under frequency protection).
Drp: Droop adjustment.
110%
135%
200%
Opening time
4 hour, minimum
1 hour, maximum
1 second, maximum
Automatic Voltage Regulator – GRT7-TH4-R2
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