Encoder monitoring: If 0x2C45='no reaction' and an encoder error is detected, reference-known is reset (corrected from V01.07.04)
Corrected from:
Servo-Inverter i950 FW: from V01.07.04.2313
Response of the new version:
The firmware of the i950 has now been adjusted as follows:
For the special case of an application described below, an additional setting option is now available to prevent the setting of the status bit in the status word 0x2831.Bit13 under the conditions described and thus also the resetting of the status reference-known.
With setting 0x2DE0:28.Bit02 = TRUE, the status bit in status word 0x2831.Bit13 is not set if the fault reaction 0x2C45 = [0] 'no reaction' or 0x2C45 = [2] 'warning' is parameterised.
In the default parameterisation, the unit continues to behave compatibly with the previous versions. The special function must be consciously activated by the user.
What happens?
Encoder monitoring:
The reference-known status is reset via the motion control, although the malfunction reaction is set to "no reaction" (not recommended).
Background:
The signal tracks of the connected encoder are monitored. With SinCos encoders, the correct relation of the two sine signal tracks to each other is monitored, with the so-called radius monitoring. As of i950 FW V01.06.04, the low and high levels of the square wave signals are checked for TTL encoders.
When an encoder error is detected, the following status bit is set, regardless of the setting of the error reaction under 0x2C45: Status word 0x2831.Bit13 "Feedback open circuit". The superimposed motion axis evaluates this status bit and resets the status to reference-known.
When does the behaviour occur?
Encoder monitoring: Fault reaction 0x2C45 = [0] ('no reaction') set and
Response of the monitoring of the encoder signals (TTL, SinCos) because the tolerance range for safe operation has been exceeded.
HTL encoders cannot actually be connected directly to the i950 servo inverter and evaluated. The HTL signals must be converted to TTL level for this. Corresponding devices for HTL-TTL level adaptation are available on the market.
From i950 FW V01.05.xx the encoder input has been extended for the use of TTL encoders (signal level 5V) and from FW version V01.06.04 monitoring of the TTL encoder signals has been introduced.
A user has used a passive circuit for level adjustment of HTL encoders (24V level) to TTL level in an application to be considered as a special case. With FW V01.05.xx this apparently worked, due to the non-existing monitoring for TTL signals. After updating the firmware to V01.06.04, however, the newly implemented monitoring of the encoder signals responded because the tolerances of the TTL signal levels were not adhered to.
