A49171 — Cooling unit: Conductivity has exceeded the alarm threshold

A49171 is an alarm from the drive's cooling unit monitoring: the conductivity of the cooling liquid has exceeded the level configured as the alarm threshold. The manuals print two slightly different cause wordings for this alarm depending on the drive object, but the remedy is the same in every case. Depending on the drive configuration, the same condition can also be signalled as a message with no reaction (N). The alarm itself causes no trip: the drive keeps its operating state and no acknowledgement is required.

• For one group of drive objects the manual states the cause directly: the conductivity of the cooling liquid has exceeded the selected alarm threshold (p0269[1]). The note printed with it says the threshold cannot be set higher than the fault threshold specified in the equipment description.
• For the other drive objects the manual words the cause as: conductivity monitoring is set for the cooling liquid, visible in bit 7 of the cooling unit status word (r0267.7), with the feedback signal source taken from p0266[7].

1. The remedy the manuals give for this alarm, for every drive object, is: Check the device to de-ionize the cooling liquid. No other corrective steps are specified.

• p0269[1] — the selected alarm threshold for the cooling liquid conductivity whose exceedance this alarm reports.
• r0267 — cooling unit status word; bit 7 (r0267.7) shows that conductivity monitoring is set for the cooling liquid.
• p0266 — BI: Cooling unit feedback signals signal source (RKA fdbk S_src); for this alarm the feedback signal source is taken from p0266[7].
• p0262 — Cooling unit fault conductivity delay time (RKA cond t_del); the manual cross-references this parameter for the alarm.
• p0261 — Cooling unit starting time 2 (RKA start time 2); the manual cross-references this parameter for the alarm.

No acknowledgement is required; the manuals specify none for this alarm. It is issued with no reaction, so nothing has to be acknowledged or reset at the drive before it continues. Under the alternative configuration (N) the same condition appears as a message with no reaction, likewise without acknowledgement.