Caterpillar — Adjustments for Stand-alone Generators (R448)
Adjustments · Voltage regulator R448
From a Caterpillar owner's manual covering: 3456, C1G1-Up, C2T1-Up, C3G1-Up, C4G1-Up, SR4B. Check it applies to your exact model before use.
Applies to: Caterpillar SR4B
Procedure
- Turn remote adjustment potentiometer to center.
- Connect analog voltmeter 100 VDC to E+ and E-.
- Connect voltmeter 300-500 VAC or 1000 VAC to generator output.
- Set ST3 wire for desired frequency.
- Turn P2 full counterclockwise.
- Turn P4 full clockwise.
- Turn stability P3 counterclockwise about 1/3.
- Start engine and set 48 Hz for 50 Hz or 58 Hz for 60 Hz.
- Adjust output voltage with P2.
- Check LAM operation, ST5 closed.
- Turn P4 slowly counterclockwise until voltage drop.
- Vary frequency around 48 or 58 Hz and check voltage.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Voltage E+ to E- approx 10 VDC
- Voltage drop approx 15%
Full service-parts list: Caterpillar SR4B →
Source: Caterpillar owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.