A06206 — Infeed: Line currents asymmetrical alarm

A06206 is the line-current symmetry monitoring of the infeed: it responds when the asymmetry of the three line currents at the terminals of the power unit exceeds the alarm threshold set in p3465. In parallel, the drive signals a possible phase failure via bit 2 of status parameter r3405 (r3405.2). Depending on how the drive is configured, the same condition can also be issued as fault F06206.

• The line supply voltage is asymmetrical, or a line phase has failed — for example because a fuse has ruptured or a terminal connection has become loose.
• Cyclic power fluctuations in the DC link with the line frequency can also result in unequal rms values of the line currents; for this type of operating scenario, the manual recommends deactivating the monitoring by setting p3465[0] = 0 and p3465[3] = 0.

1. Check the line supply, the terminals and the fuses.
2. Check the line supply quality and the system fault level.
3. Check the load.
4. Check the settings in p3462 (infeed phase failure detection times) and p3465 (infeed current symmetry monitoring thresholds).

• The drive stores the alarm value as a floating-point number in r2134.
• Digits to the left of the decimal point: highest rms phase current in amps.
• Decimal places: quotient of the lowest and the highest rms phase current value.

• p3465 — infeed current symmetry monitoring thresholds: the alarm threshold this code responds to; setting p3465[0] = 0 and p3465[3] = 0 deactivates the monitoring.
• p3462 — infeed phase failure detection times: check this setting together with p3465 as part of the remedy.
• r2134 — alarm value for float values: read here the highest rms phase current (digits left of the decimal point) and the ratio of lowest to highest rms phase current (decimal places).

As an alarm, A06206 does not force the drive out of its operating state and requires no acknowledgment: once the three line currents are balanced again and remain within the threshold in p3465, the alarm goes away by itself. If the drive raises the condition as fault F06206 instead, the fault must be acknowledged before it is deleted — immediate acknowledgment is sufficient, a POWER ON is not required. Because the code itself does not switch the drive off, no special restart sequence is needed once the line supply has been restored to a symmetric state.