A07577 — Encoder 1: Measuring probe evaluation not possible

A07577 appears on encoder 1 when the drive cannot evaluate the measuring probe signal: an error occurred while the probe was being evaluated. Depending on how the drive is configured, the same condition can also be issued as a fault instead of an alarm. The alarm value stored in r2124 states which of four possible errors is present.

• An error occurred while the drive was evaluating the measuring probe on encoder 1; the alarm value in r2124 identifies which of the four problems below exists.
• Alarm value 6: no input terminal has been assigned for the measuring probe.
• Alarm value 4098: initialization of the measuring probe failed.
• Alarm value 4100: the frequency of the measuring pulses is too high.
• Alarm value 4200: the PROFIBUS clock cycle is not an integer multiple of the position controller clock cycle.

1. Read the alarm value in r2124 as a decimal number; it tells you which of the four errors is present.
2. If the measuring probe evaluation is not needed, switch it off by applying signal 0 to BI p2509 — this resolves the condition regardless of the alarm value.
3. Alarm value 6: assign the input terminal for the measuring probe, either in p0488 and p0489 or in p2517 and p2518.
4. Alarm value 4098: inspect the Control Unit hardware.
5. Alarm value 4100: lower the frequency of the pulses delivered by the measuring probe.
6. Alarm value 4200: change the clock cycle configuration so that the PROFIBUS clock cycle is an integer multiple of the position controller clock cycle.

• The drive writes the alarm value into r2124; interpret it as a decimal number.
• 6 — probe input terminal missing.
• 4098 — probe initialization failed.
• 4100 — probe pulse frequency too high.
• 4200 — PROFIBUS/position controller clock cycle ratio wrong.

• r2124 — read the alarm value stored here as a decimal number to see which of the four errors tripped the alarm.
• p2509 — a signal 0 at this BI input switches the measuring probe evaluation off, ending the condition when the probe is not needed.
• p0488 — assigns the input terminal for measuring probe 1; the place to set it when alarm value 6 is shown.
• p0489 — assigns the input terminal for measuring probe 2; the second terminal for alarm value 6.
• p2517 — input for the LR direct measuring probe 1; an alternative way to assign the terminal for alarm value 6.
• p2518 — input for the LR direct measuring probe 2; likewise an alternative for alarm value 6.

As an alarm, A07577 clears itself once the cause no longer applies; no acknowledgment action is needed. If the drive configuration raises the same condition as a fault instead, the drive performs an OFF1 stop, and the fault must be acknowledged immediately before the drive can be restarted.