Siemens SINUMERIK 840Di Diagnostic Manual page 53

11/2006
4240 Runtime overflow for IPO cycle or position controller cycle, IP %1
Parameters: %1 = Program location
Definitions: The settings for the interpolation and position control cycle were modified before the last power-up
such that too little computing time is now available for the requisite cyclic task.
The alarm occurs immediately after power-up if too little runtime is available even when the axes are
stationary and the NC program has not started. However, task overflow can occur only when
computation-intensive NC functions are called during program execution.
Reaction: NC not ready.
The NC switches to follow-up mode.
Mode group not ready, also effective for single axes
NC Start disable in this channel.
Interface signals are set.
Alarm display.
NC Stop on alarm.
Alarm reaction delay is canceled.
Remedy: Please inform the authorized personnel/service department. Take greater care when optimizing the
clock times NCK MD 10050 SYSCLOCK_CYCLE_TIME, MD 10060
POSCTRL_SYSCLOCK_TIME_RATIO and/or MD 10070 IPO_SYSCLOCK_TIME_RATIO.
The test should be performed with an NC program that represents the worst case. For safety, a margin
of 15 to 25% should be added to the times determined in this way.
Program Switch control OFF - ON.
Continuation:
4250 FastPlcCom functionality not available
Definitions: This alarm indicates that the PLC provides the None FastPlcCom functionality during start-up
although this functionality is requested by the NCK.
Reaction: Alarm display.
Remedy: Retrofit the PLC with the FastPlcCom functionality or deactivate the FastPlcCom functionality by
means of NCK machine data.
Program Clear alarm with the RESET key. Restart part program
Continuation:
4252 PLCIO read error: %1
Parameters: %1 = PLCIO error code
Definitions: This alarm indicates that errors occured when reading the PLCIO with the FastPlcCom functionality.
Reaction: Alarm display.
Remedy: Check machine data MD 10394/10395 or check the PLC hardware configuration.
Program Clear alarm with the RESET key. Restart part program
Continuation:
4254 PLCIO write error: %1
Parameters: %1 = PLCIO error code
Definitions: This alarm indicates that errors occured when writing on the PLCIO with the FastPlcCom functionality.
Reaction: Alarm display.
Remedy: Check machine data MD 10396/103947 or check the PLC hardware configuration.
Program Clear alarm with the RESET key. Restart part program
Continuation:
© Siemens AG, 2006. All rights reserved
SINUMERIK, SIMODRIVE Diagnostics Manual (DA), 11/2006 Edition
Overview of Alarms
NCK alarms
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