Rosemount 3051 Error Code R021

Rosemount SCADA Major Power

Model: 3051 | Code: R021

Applicable Systems
3051

Symptoms

The 3051 reports a DC bus undervoltage fault. The drive trips because the bus voltage dropped below the minimum operating level.

Possible Causes

  • Input power supply voltage dip or momentary outage
  • Power supply capacity insufficient for the drive load
  • Loose or corroded power wiring connection causing voltage drop

Troubleshooting Steps

  1. Step 1: Measure the input supply voltage during operation with a power analyzer
    Voltage remains stable within the rated range
  2. Step 2: Tighten all power wiring connections at the drive terminals
    All connections are tight with no voltage drop
  3. Step 3: If power dips are frequent, install a voltage stabilizer or UPS
    Supply voltage is stable and above the minimum

How to Reset

To reset: Restore the supply voltage to the rated range, then reset the fault.

Source: Rosemount 3051 Pressure Transmitter Manual, Emerson Process Management

Category: SCADA