ALARMS
If you have a Y03 Alarm, there will be an axis number displayed to the right of the alarm. This alarm means that the NC believes that axis is not connected to the system. First check that all of the servo amplifiers are connected and that they are all being supplied with AC voltage normally labeled R and S. Also check for the presence of the DC Link on all three axes. Make sure the Serial Buss is daisy chained to all of the amps and to the spindle. Check all of the rotary selector switches on the amps and the spindle to be sure they are in the correct position. The description of this alarm in the manual indicates a hardware fault as the likely culprit but in most cases you will probably find a parameter set wrong so if you have a copy of the parameters you might want to go ahead and reload them.
Alarm Y06 is basically the same deal and will always be a parameter If you have the alarm Y03 AMP UNEQUIPPED XYZA and alarm EMERGENCY STOP LIN, there is a good chance the CPU is not communicating with the amplifiers. In this case, the likely suspects are the serial cables, the terminator plug or the communication board QX721 or QX722. The control will have one of these boards are the other. It is a small board which is mounted piggyback on the CPU board. A good test for this case is to replace the cable that goes from the CPU to the first amplifier. In the field this may be difficult. You can take a cable from between two of the amps is long enough and connect it to port CN1A of the first amp and to the CPU. Place the terminator on port CN1B of this amp. If the cable was bad, when you power up this time the alarm should say something different depending on which amp you are connected to. For example, Y03 AMP UNEQUIPPED YZA or XZA. In this case, replacing the cable should solve the problem. The communication boards do go bad sometimes so don't be afraid to replace it if you cannot effect a change by moving cables around. Anytime you have the Y03 alarm along with other alarms there is a way to bypass the alarm so you can work on the other problems. Remove the cable from CSH21 on the CPU and insert the terminator plug into the port. Go to the Machine Base Parameter NOAMP and make it a 1. This will tell the NC that no amps are installed and the alarm will go away.
Also for the Y03 AMP UNEQUIPPED ALARM, if you get this after replacing or adding an amplifier, make sure the DIP switches on the amps are set correctly to identify the axes to the NC.
Often times you will have an alarm such as S52 Servo Warning 00E6 X. This does not always mean there is a problem with the X axis. Sometimes there will be a problem communicating with all of the servos but if X is the first in the string, the NC may issue this alarm. If you have an alarm like this in conjunction with an EMG Emergency PLC alarm the problem may have nothing to do with the servos at all. In this case the problem could be with something such as the Keypad Interface Card in the pendant. In particular, if the four pin cable that goes to J4 on the keypad interface card is removed, damaged, etc. this alarm will definitely occur. This cable uses two of the four wires. They connect to 24vdc on the external power supply.
MDS-A-SPJA-75RT
AL-30 on this amplifier is a regenerative alarm. It can occur if the AC Line exceeds 260 volts or if the regenerative braking system (resistor) fails. Experience has shown that it usually means that the amplifier is bad. AL-24 is a Ground Fault alarm, it normally occurs if a motor is grounded or one of the AC power leads is accidentally swapped with a motor lead.
The following is a nearly complete list of Mitsubishi Alarms as displayed on the drives. Depending on the specific drive, the LED display may show an A or an AL along with the number but the meaning is the same. Some alarm numbers shown here may appear on other Mitsubishi drives and their meanings may be other than indicated here. Also, an effort is made here to distinguish Servo alarms from Spindle alarms by entering SV or SP after the description. Due to the various uses and configurations of drives as well as typing errors etc., you have to use your best judgment when applying these alarms to your situation.
The following are for MDS drives.
10 UNDERVOLTAGE The P-N Bus voltage is 200V or less.
SV, SP
11 AXES SELECTION
ERROR (ASE) 
The axis setting rotary switch was set 




illegally in the two axis integrated amp (dual 


amp).
SV
12 MEMORY ERROR 1 The memory IC (SRAM or FROM) check sum was illegal.
(ME1)
SV, SP
13 SOFTWARE PROCESS The software data processing was not completed within the normal time.
ERROR (SWE)
SV, SP
14 UNDEFINED
15 MEMORY ERROR 2 Memory error on the servo drive.
(ME2)
SV
16 POLE POSITION The differential input of the U, V or W phase of the pole position detection signal of the OHE type
ERROR (RD1) type detector were both "H" or "L".
17 A/D CONVERTER The A/D converter for current detection did not function properly during initialization.
(ADE)
SV, SP
18 INITIAL COMM. ERROR The Absolute position or pole position data 


from the type detector was not correctly sent.
(WAT)
SV
19 UNDEFINED
1A SERIAL DETECTOR Initial communication with the serial encoder installed on the ballscrew end was not possible.
COMM. ERROR
(STE1)
SV
1B CPU ERROR SUB An error was detected in the data stored in 



the of the serial pulse coder installed on the ball
(SCPU) EEPROM screw end.
SV
1C LED ERROR SUB Deterioration of the LEDs in the serial pulse
(SLED)
coder installed on the ball screw end was 



SV detected.
1D DATA ERROR SUB An error was detected in the per rotation 
(SDAT)
position data of the serial pulse coder 




installed
SV on the ball screw end.
1E SERIAL DETECTOR The thermal protector built in the detector 



operated in the serial pulse coder installed 



on
ERROR SUB the ball screw end.
(SOHE) SV
1F SERIAL DETECTOR Communication with the detector in the serial pulse coder installed on
COMMUNICATION the ball screw end was cut off.
ERROR SUB (STRE)
SV
20 NO SIGNAL DETECTED The differential input of the A, B or Z phase 1 signal from the motor end installed detector
(NS1) were both H or L.
SV
21 NO SIGNAL DETECTED The differential input of the A, B or Z phase 2 signal from the machine end installed detector
(NS2) were both H or L.
SV, SP
22 NO SIGNAL DETECTED The serial input of the A, B or Z phase signal 3 from the motor end installed detector were
(NS3) both H or L.
SV
23 SPEED DEFLECTION The speed command and motor speed deflection exceeded the specified value and the state
EXCESSIVE for a specified time.
(OSE) SP
24 GROUND FAULT A motor cable ground fault was detected.
SV, SP
25 ABSOLUTE POSITION A serial data counter error received from the absolute value detector (excluding scale) was detected
LOST (ABSE) during creation of the absolute position after the NC power was turned on.
SV
26 NOT-USED AXIS ERROR The rotary switch was set to F and an IPM error occurred in an axis not being controlled.
(NAE)
SV
27 ABSOLUTE POSITION An error was detected in the CPU of the absolute position linear scale.(Alarm output
DETECTION SCALE by the detector. CPU by the detector)
ERROR SV
(SCCPU)
28 ABSOLUTE POSITION The scale moved at 45 mm/sec or higher when the NC power was turned on for the absolute
OVERSPEED position linear scale or the detector rotated at 500 rpm or higher when the drive power was
(SOSP) off with the HA-FA motor.
SV
29 ABSOLUTE POSITION An error occurred in the absolute position detection circuit of the absolute position
DETECTOR CIRCUIT linear scale or HA-FH motor built-in detector.
ERROR
(SABS) SV
2A INCREMENTAL POSITION The movement speed exceeded 60 m/min in the absolute position linear scale.
DETECTOR CIRCUIT
ERROR SV
(SINC)
2B CPU ERROR The CPU for the absolute position linear scale or HA-FH motor built-in detector did not
(SCPU) operate correctly.
SV
2C LED ERROR An LED error was detected by the HA-FH motor built-in detector.
(SLED)
SV
2D DATA ERROR An error was detected in the per rotation position data of the serial pulse coder
(SDAT) installed on the motor end.
SV
2E UNDEFINED
2F SERIAL DETECTOR Communication error with the high speed serial detector.
COMMUNICATION
ERROR SV
(STRE)
30 OVER REGENERATION Overheating of the regenerative resistor was detected.
(OR)
SV, SP
31 OVERSPEED Motor speed exceeded the tolerable speed.
(OS) SV, SP
32 POWER MODULE ERROR The IPM used in the amplifier detected over current.
IOC (PME)
SV, SP
33 OVERVOLTAGE The PN buss wire voltage exceeded 400V.
SV, SP
34 CRC ERROR There was an error in the communication data from the NC.
(DP)
SV, SP
35 CNC COMMUNICATION The movement command data sent from the NC was excessive.
DATA ERROR
SV, SP
36 CNC COMMUNICATION There was an error in the communication data from the NC.
ERROR
(TE) SV, SP
37 INITIAL PARAMETER Parameter error.
ERROR SV, SP
(PE)
38 CNC COMMUNICATION A protocol error occurred in the communication with the NC (Framing Error).
PROTOCOL ERROR 1
(TP1) SV, SP
39 CNC COMMUNICATION A protocol error occurred in the communication with the NC(Information Error).
PROTOCOL ERROR 2
(TP2) SV, SP
3A OVERCURRENT The current (detection value) for motor drive is excessive.
(OC)
SP
3B POWER MODULE ERROR The IPM overheat detection functioned.
(PMOH) SV, SP
3C REGENERATIVE CIRCUIT An error was detected in the regenerative transistor or resistor.
ERROR 3C
3D UNDEFINED
3E UNDEFINED
3F UNDEFINED
40 A-TK UNIT Detected when the changeover input sequence was mistaken during use of the TK unit with
CHANGEOVER ERROR the one amplifier, two motor function.
(KE)
SP
41 A-TK UNIT Detected when an error occurs in the data communication during use of the TK unit with the one
COMMUNICATION amplifier, two motor function.
ERROR 2
(KE2) SP
42 FEEDBACK ERROR 1 A skip of the detector feedback signal pulse occurred in the OHE type or OHA type detector
(FE1) used in the semi-closed loop system and ballscrew end closed loop system. A skip of the
SV detector feedback signal pulse in the low speed type serial type absolute position linear scale.
43 FEEDBACK ERROR 2 A deviation occurred in the feedback amount from the motor end detector and machine
(FE2) end detector in the closed loop system.
SV
44 C AXIS CHANGEOVER When using the coil changeover motor, C axis control was carried out without the H coil.
ALARM
(CAXC) SP
45 UNDEFINED
46 MOTOR OVERHEAT Check motor temperature, check overheat sensor.
(OHM)
SV, SP
47 UNDEFINED
48 UNDEFINED
49 UNDEFINED
4A UNDEFINED
4B UNDEFINED
4C UNDEFINED
4D UNDEFINED
4E UNDEFINED
4F INSTANTANEOUS STOP The power was cut off for 50 milliseconds or more.
SV, SP
50 OVERLOAD DETECTION 1 The time that motor current exceeded the parameter (overload detection level) in the stall
OLL ratio conversion was longer than parameter OLT (overload level).
(OL1)
SV, SP
51 OVERLOAD DETECTION 2 A current command exceeding 95% of the amplifier's maximum current continued for one
(OL2) second or more.
SV, SP
52 EXCESSIVE ERROR 1 The actual position droop for the ideal droop exceeded the parameter setting value OD1
DURING SERVO ON (excessive error width during servo on).
(OD1)
SV, SP
53 EXCESSIVE ERROR 2 The actual position droop for the ideal droop exceed ed the parameter setting value OD2
DURING SERVO OFF (excessive error width during servo off).
(OD2)
SV, SP
54 EXCESSIVE ERROR 3 The motor current did not flow when the excessive error 1 alarm was detected
(OD3) (added with the B series).
SV
55 UNDEFINED
56 UNDEFINED
57 UNDEFINED
58 COLLISION A collision detection type 1 error was detected during the G0 modal (rapid traverse).
DETECTION 0
(CLE0) SV
59 COLLISION A collision detection type 1 error was detected during the G1 modal (cutting feed).
DETECTION 1
(CLE1) SV
5A COLLISION A collision detection type 2 error was detected.
DETECTION 2
(CLT2) SV
5B UNDEFINED
5C ORIENT FEEDBACK The pulse miss value was higher than the parameter set value (SP114:OPER)
ERROR when orientation positioning was completed.
(ORFE)
SP
5D UNDEFINED
5E UNDEFINED
5F UNDEFINED
60 RESISTOR The resistor regeneration unit's DC24V voltage dropped.
REGENERATION 24V
VOLTAGE DROPPED
SP (0)
61 POWER MODULE An over current was detected with the power supply units IPM.
OVERCURRENT (1)
CV
62 (2) Not Used
63 AUXILIARY The auxiliary regeneration transistor in the power supply unit is short circuited.
REGENERATION
ERROR (3)
CV
64 GROUNDING 2 Regeneration actuated immediately after the ready on.
(4)
CV
65 RUSH CURRENT ERROR The rush relay in the power supply unit is excited but not turned on.
(5)
CV
66 (6) Not Used
67 OPEN PHASE The R, S or T input of the power supply unit is open.
(7)
CV
68 WATCH DOG The power supply software process did not end within the designated time.
(8)
69 GROUND FAULT A ground fault occurred in the motor.
(9) CV
6A CONTACTOR FUSE Welding of the power supply unit external contactor was detected.
(A)
CV
6B RUSH RELAY FUSE Welding of the rush relay in the power supply unit was detected.
(B)
CV
6C MAIN CIRCUIT ERROR The main circuit capacitor in the power supply could not be charged correctly.
(C)
CV
6D PARAMETER ERROR When NC power is turned on.
(D)
CV
6E MEMORY ERROR An error occurred in the power supply unit's memory circuit.
(E)
CV
6F A/D ERROR An error occurred in the power supply unit's A/D converter section.
(PS ERROR)
SP, CV
70 (G) UNDEFINED
71 POWER SUPPLY An instantaneous power failure exceeding 25ms was detected in the power supply unit.
INSTANTANEOUS
POWER FAILURE
(H)
CV
72 (I) UNDEFINED
73 OVER REGENERATION The regenerative load in the resistor regeneration unit exceeded the standard value.
(J)
CV
74 REGENERATIVE The regenerative resistor's thermal protector functioned.
RESISTOR OVERHEAT
(K)
CV
75 OVERVOLTAGE The power supply unit's PN buss voltage exceeded 410 volts.
(L)
CV
76 EXTERNAL EMERGENCY When NC power is turned on.
STOP SETTING ERROR
(M)
CV
77 POWER MODULE The IPM in the power supply unit detected an overheat.
(V)/FIN (R) OVERHEAT
(N)
CV
78 UNDEFINED
79 UNDEFINED
7A UNDEFINED
7B UNDEFINED
7C UNDEFINED
7D UNDEFINED
7E UNDEFINED
7F UNDEFINED
80 UNDEFINED
81 UNDEFINED
82 POWER SUPPLY A no signal was detected in the communication line with the power supply.
NO SIGNAL
(NSP)
SV, SP, CV
83 UNDEFINED
84 UNDEFINED
85 UNDEFINED
86 UNDEFINED
87 UNDEFINED
88 WATCH DOG The servo amplifier software process did not end within the designated time.
(WD)
SV
89 UNDEFINED
8A UNDEFINED
8B UNDEFINED
8C UNDEFINED
8D UNDEFINED
8E UNDEFINED
8F UNDEFINED
90 LOW SPEED SERIAL Communication with the absolute position linear scale was not possible when the
INITIAL COMMUNICATION NC power was turned on.
ERROR (WAT)
SV
91 LOW SPEED SERIAL During normal operation, the absolute position data was not transmitted from the low
COMMUNICATION speed serial detector
ERROR (WAS)
SV
92 LOW SPEED SERIAL During normal operation, the absolute position data transmitted from the low speed
PROTOCOL ERROR serial detector.
(WAF) SV
93 ABSOLUTE POSITION The absolute value counter could not be set when the power was turned on because
FLUCTUATION the absolute position had fluctuated.
(WAM)
SV
94 UNDEFINED
95 UNDEFINED
96 MP SCALE In the MP scale absolute detection system, an excessive deviation in the motor end
FEEDBACK ERROR installation detector and MP scale feedback amount was detected.
(MPE)
SV
97 MP SCALE OFFSET In the MP scale absolute position detection system, an error was detected in the offset
FLUCTUATION data read when the NC power was turned on.
(MPO)
SV
98 UNDEFINED
99 UNDEFINED
9A UNDEFINED
9B UNDEFINED
9C UNDEFINED
9D UNDEFINED
9E HIGH SPEED An error was detected in the multi-rotation counter in the serial encoder installed on the
SERIAL DETECTOR the ballscrew end.
ERROR (WAN)
SV
9F BATTERY VOLTAGE The voltage of the battery supply to the absolute position detector dropped.
DROP (WAB)
SV
A0 UNDEFINED
A1 UNDEFINED
A2 UNDEFINED
A3 UNDEFINED
A4 UNDEFINED
A5 UNDEFINED
A6 UNDEFINED
A7 UNDEFINED
A8 TURRET INDEX NO DEFINITION
COMMAND ERROR SP
WARNING
(WTW)
A9 UNDEFINED
AA CNC INITIAL Waiting for NC power on after power off.
COMMUNICATION SV, SP
PHASE 1 WAIT CNC
AB CNC INITIAL Waiting for NC power on for the first time.
COMMUNICATION SV, SP
PHASE 1 WAIT
AC CNC INITIAL Initializing. Requisition parameter transmission.
COMMUNICATION SV, SP
PHASE 2 WAIT
AD CNC INITIAL Initializing. Requisition parameter conversion.
COMMUNICATION SV, SP
PHASE 3 WAIT
AE CNC INITIAL Initializing. Standby for main servo IT start.
COMMUNICATION SV, SP
PHASE 4 WAIT
AF RESERVED
B0 IN READY OFF DURING SERVO INITIALIZATION.
SV, SP
B1 " "
B2 " "
B3 " "
B4 " "
B5 " "
B6 " "
B7 " "
B8 " "
B9 " "
BA " "
BB " "
BC " "
BD " "
BE " "
BF " "
C0 READY ON AND Machine and control ready but servo not running.
SERVO OFF
SV, SP
C1 " "
C2 " "
C3 " "
C4 " "
F6 RESERVED FOR AXIS
NUMBER INDICATION.
SV, SP
F7 " "
F8 " "
F9 " "
FA UNDEFINED
FB UNDEFINED
FC UNDEFINED
FD UNDEFINED
FE UNDEFINED
FF UNDEFINED
0 UNDEFINED
1 FLASH PROGRAMMING During re-writing of software.
ERROR SV, SP
2 FLASH ERASE ERROR During re-writing of software.
SV, SP
3 VPP ERROR "
4 CHECK SUM ERROR "
5 COMPARE ERROR "
6 UNDEFINED
7 UNDEFINED
8 BANK DESIGNATION During re-writing of software.
ERROR
SV, SP
9 INITIAL ADDRESS "
ERROR
A BANK CHANGEOVER "
ERROR
B ADDRESS ERROR "
C RECEPTION TIME "
ERROR
D UNDEFINED
E UNDEFINED
F COMMAND SEQUENCE During re-writing of software.
ERROR
SV, SP
The following list of alarms are associated with regeneration problems. Some of the alarms are include in the list above but this listing supplies additional information. Also, the number or letter in the column to the right of the alarm code refers to what will be displayed on the resistance regeneration converter unit. In addition, the two digit letter code beneath the alarm code refers to how the alarm can be reset.
AR = By turning the converter unit power off and back on.
PR = By turning the NC power off and back on.
NR = By pressing the NC Reset.
60 0 INSTANTANEOUS STOP The 24vdc dropped.
PR
63 3 REGENERATION ERROR The regeneration transistor turned on while the regeneration command was off.
PR
65 5 RUSH RELAY ERROR The rush relay does not turn on and chattering occurs.
PR
68 8 WATCH DOG CPU runaway.
AR
69 9 GROUND FAULT Driver UVW ground fault.
PR
6B b RUSH RELAY MELT The rush relay did not turn off.
PR
6C C MAIN CIRCUIT ERROR The buss is short circuited, the charge to the main CIRCUIT IS ABNORMAL.
PR
6D d PARAMETER ERROR The regenerative resistor setting is not adequate.
PR ERROR
6E E MEMORY ERROR The memory cannot be read/written correctly.
AR
73 J OVER-GENERATION The regeneration load was exceeded.
PR
74 t REGENERATION The regenerative resistor thermal functioned.
RESISTOR OVERHEAT
PR
75 L OVERVOLTAGE The buss voltage rose.
NR
77 n PCB OVERHEAT Overheating of the thermal in the amplifier.
PR
E8 o OVER-REGENERATION 80% of the over regeneration alarm level.
REGENERATION
WARNING
The following list of alarms can be found in the manual,
MITSUBISHI
AC SPINDLE DRIVE
MDS-1-SPJA SERIES
SPECIFICATIONS AND MAINTENANCE MANUAL
Z MEMORY A Check Sum or RAM error occurred in the spindle drive
ERROR 1 control card ROM.
S04 Alarms:
S04 SERVO ALARM: AR 00?? ?
The two numbers after the two zeros are the actual alarm number and are typically displayed on the amplifier or power supply. If you see a number between 60 and 80 it is normally a power supply (CV unit) problem. The letter display ed after the alarm number is normally an axis designation such as X, Y, etc. If the letter is S or T, refer to the spindle alarm section. These alarms always require that the drive (main) power must be cycled to remove the alarm.
11 ASE Spindle Selection Error
In MDS-B-B24 driver, the rotary selector switches for both axes are set to the same axis number when using the 2 axis
integrated amplifier. Otherwise, the switches are set to an illegal value.
12 ME Memory Error
An error was detected in a memory IC or FB IC by self-check to be made during driver power-on.
25 ABSE Absolute Position Data Lost
The backup voltage in the absolute position detector dropped. The absolute position cannot be compensated.
68 PWD Power Supply Watchdog
The S/W process did not complete in a specified time.
6E PME Power Supply Memory Error
Memory error was detected on the power supply unit. (Alarm E on the power supply unit.) An error occurred in the memory
circuit.
6F PSE Power Supply Alarm
The power supply unit is not connected. Otherwise, an error was detected in the A/D converter of the power supply.
76 Power Supply External Emergency Stop
Setting Abnormal
External emergency stop setting abnormal alarm is generated in the power supply unit. (M on the power supply display).
The rotary switch setting and parameter (PYTP) setting do not match.
77 Power Module or PC Board Overheated
Power module or PC overheated alarm is generated on the power supply unit. (n on the power supply unit).
84 HCPU HR Unit CPU Error
The CPU of MDS-B-HR connected with the motor and does not operate properly.
88 WD Watch Dog
Servo system operation is abnormal.
8D Hcpu HR Unit CPU Error
The CPU of MDS-B-HR connected with the (SUB) machine and does not operate properly.
When AL-25 is displayed on an amplifier, it means the Absolute Position has been erased. Normally, if you turn the power off then back on it will go away. Sometimes it helps to hold the NC power on button while the control is powering up. On some machines it will be necessary to reset the axes zero positions once the alarm is gone.
Alarm AL-A1 is normal sometimes when you swap servo amplifiers. It means that when the amplifier powers up it sees an absolute position other than what it expects to see. In other words the amplifier stores the position of the axis relative to the marker pulses of the encoder and when it powers up and compares this to the position of the pulse coder and sees a difference, the alarm is generated. This is a fairly low priority alarm and will not be displayed if other pulse coder alarms are present such as AL-16 which is a communication problem between the pulse coder and amp.
For alarm E51 FILE OPEN ERROR, check how much memory is available. In some cases the memory may get reset to 0 for the amount Free and the amount Used. This is more or less common if you change an Option Parameter, especially the memory size parameter (prosiz). To resolve the problem, change fix_p to 1 and Format the control.
P461 FILE I/O ERROR will normally result from not re-loading the Fixed Cycles after formatting the control.
If alarm S52 M01 0102 is issued when taking a cut, check Machine Servo Parameters SV021 and SV022. SV022 specifies the current detection level of overload 1 (OL1) with respect to the stall rating (%). Setting range is 1-500%. Parameter SV021 specifies a time constant for detection of of overload 1 (OL1). The setting range is 1-1800 seconds. What all this means is that if you have an axis which the axis faults or alarms during a cut parameter SV022 tells the control what level of current or motor load is allowable, SV021 tells the control how long the motor is allowed to pull this amount of current.
The alarms on the M300 control are almost identical to the M500.
Alarm E10 MEMORY OVER means that a value was set in the parameter PROSIZ that exceeds the hardware memory capacity of the control.
You cannot put a negative value in the Grid Shift parameter (G28sft). If you try to the control will issue the E02 DATA OVER alarm.
Regardless of which alarm is displayed on the CRT, the important thing is the four numbers at the end of the line (i.e. 006C), this tells the story of what the control thinks is wrong.
Not every manual lists or explains the S04 servo alarms, below is a partial list.
11 ASE Spindle Selection Error
In MDS-B-B24 driver, the rotary switches for both axes are set to the same axis number when using the 2 axis integrated
amplifier or the switches are set an illegal value.
12 ME Memory Error
An error was detected in a memory IC or FB IC by self-check to be made during driver power up sequence.
25 ABSE Absolute Position Data Lost
The backup voltage in the absolute position detector dropped. The absolute position cannot be compensated.
68 PWD Power Supply Watchdog
The software process did not complete in the specified time.
6E PME Power Supply Memory Error
"Memory Error" was detected on the power supply unit side (Alarm E on the power supply unit). An error occurred in the
memory circuit.
6F PSE Power Supply Alarm
The power supply unit is not connected or an error was detected in the A/D converter of the power supply.
76 Power Supply External Emergency Stop
Setting Abnormal
E-Stop Setting Abnormal alarm is generated on the power supply unit side. (M on the power supply unit) or the rotary
switch setting and parameter (PTYP) setting do not match.
77 Power Module or PC Board Overheated
Power module or PC board overheated alarm is generated on the power supply unit side (n on the power supply unit).
84 HCPU HR Unit CPU Error
The CPU of MDS-B-HR connected with the motor end does not operate properly.
88 WD Watch Dog
Servo system operation is abnormal.
8D Hcpu HR Unit CPU Error (SUB)
The CPU of MDS-B-HR connected with the machine end does not operate properly.
When adjusting for spindle orientation position shift (OPST) on an M520 or M530 control, it is sometimes not necessary to orient the spindle after adjustment to check the shift amount. If the machine uses a magsensor for orientation, when you change the parameter and press INPUT, the spindle will move the shift amount difference.
When the EDIT LOCK (hardware) of a machine with an M520 control is switched on and off, the Main Program display will switch from ABC, etc. to blank. Parameter will switch from ON to OFF.
Typically, if the spindle motor is phased wrong on a machine with a Mitsubishi drive the motor will run slower than commanded, may move jerkedly, may run one direction when M03 commanded the other direction when M03 commanded again, eventually will generate alarm S03 PR 23.
For alarm S01 PR 16 check the motor lead connections. What normally happens is the military style connector backs off the motor. You may check the leads and the windings will appear normal but the higher resistance causes the alarm. This alarm can also be hard to get rid of even once a good connection has been established. I have found that the main power sometimes has to be turned off for up to 30 minutes to reset the alarm or in some cases must be cycled several times.
520AMR
On a machine which uses a magsensor for spindle orientation, spindle parameter should be set to 0002. On a machine which uses a proximity switch it should be 8002. If it is set for 0002 on a machine that uses a proximity switch, when spindle orientation (M19) is commanded the spindle will go to the orientation point then start to drift normally in the opposite direction of orientation. Also, the spindle may orient in different directions.
Mitsubishi YM control (Normally found on Mazatrol M2):
For alarm 22:SUM CHECK ERROR (parity alarm), find PCB FX01 or FX701 and pull it out of the rack far enough to access the DIP switch. Place the second switch from the top in the opposite position, re-seat the board. Cycle the NC power (several times if necessary) to remove the alarm. It may take as much as ten times and the time off may have to made longer to clear it. Once the alarm is cleared, place the switch to it's original position.
The CV unit (power supply) MDS-B-CV-185 can be swapped with the MDS-B-CVE-185 for testing purposes only because the two are specified with different AC Reactors.
If the spindle motor makes a growling noise even with the belts off, the spindle amplifier, motor or cables could be bad, of course, but another possibility is the PLG which controls the spindle amp. To rule this out as the cause as well as, to a certain extent, the motor encoder and feedback cable you can run the spindle in open loop mode. To do this change the leftmost bit of spindle machine parameter SP038 (SFNC6) to 8. That is, if the parameter currently is 0000, change it to 8000. If it is currently 0001, make it 8001, etc. You can not run the spindle to fast in this mode, start off at 50 rpm then work your way up to about 1000 rpm. If the growling goes away, the PLG is probably bad. The power has to be cycled all the way down to the breaker in order for the parameter to take effect and for the new data to be loaded to the spindle amplifier.
Where the serial cables for the amplifiers are concerned, on most Mitsubishi M530 equipped machining centers they will connect this way. Serial communication cable from CPU to CN1A of PSM, CN1B of PSM to CN1A of first servo amp, CN1B of first servo amp to CN1A of second amp, CN1B of second amp to CN1A of third amp. CN1B of third amp will have a terminator on CN1B unless the machine has a fourth axis in which case the fourth axis CN1B is terminated and CN1B of the third amp is connected to CN1A of the fourth axis amp. Also CN4 of the spindle amplifier is normally connected to CN4 of the PSM. Failure to meet any of these conditions will cause the Y03 AMP UNEQUIPPED alarm.
To access the timers for the M50 control:
1. TOOL/PARAM button.
2. SETUP soft key.
3. (Y)
4. PLC soft key.
5. Page down to the timers.
If the spindle on a machine with an M50 control will not hold rigid enough you can adjust parameter 3202 (PGE) Encoder orient Position Loop Gain.
On an M50 controlled machine that uses G30 as a tool change position, etc. you can shift the position with parameter 2038 _rfp.
M530 control:
Axis Specification Parameter G0inps sets the in position width for Rapid mode. Specification parameter G1inps sets the in position width for cutting feed rate.
Alarm AL-25 is described by the manual as ABSOLUTE POSITION ERROR (Absolute Position has been Erased). Many times this alarm can be cleared by simply turning the control power off then back on. If the control is one that uses an ON/OFF switch for the NC power, it may be helpful to hold the ON push button for a few minutes, the turn the NC off and back on. For machines like the Ecoca PC lathe on which the NC comes on with the main power, you might track down the relay that does this and perhaps make it hold in. Other causes for this alarm may be a bad battery or broken battery cable. The amplifier issues an alarm if the battery voltage drops below a certain level.
If you get alarm P on a MDS-B-CV-185 power supply (CV unit), check terminal MC1 on the unit. On an Ecoca the wires of the three terminals are labeled:
200R
200S
200
When you have alarm EMG EMERGENCY LIN it sometimes means that the control has detected a problem that it can not define. The first thing you should check is the R69 bits, they should all be 1. If they are not, identify the bit that is zero and check with the manual to see what it pertains to. One thing that will cause this alarm is if the cables are connected wrong on an amplifier, in particular CN1A and CN1B. CN1A of an amplifier should always go to CN1B of another amp, CN1B should always go to CN1A of another amp. If you get CN1A and CN1B of an amp switched around you will get this alarm and the amplifiers will flash E7. If you check R69 you will find 11111101
11111111
Alarm Z70 occurs anytime the zero position needs to be reset for any reason. Alarm Z71 typically occurs when there is a problem with either the battery for the absolute pulse coder, the pulse coder itself or the servo amplifier.
Possible Z70 ABSOLUTE POSITION ERROR alarms are as follows:
0001 Origin initialization is not complete
Execute origin initialization (Absolute Position set).
0002 Absolute position reference point data stored in NC is lost.
Normally this can be resolved by loading the machine's parameters. Doing this will restore the absolute positions exactly
to what they were prior to being lost. If the parameters are not available, execute origin initialization.
0003 The parameters used to detect absolute position is changed or destroyed.
Set the parameter(s) to the correct value, cycle NC power, execute origin initialization. You may also try loading the
machine's parameters only.
Possible Z71 DETECTION BLOCK ERROR alarms are as follows:
0001 The backup voltage in the absolute position detector dropped.
Charge or replace the battery, check the cable for connection and/or check the pulse coder. Initialize the zero point
after the power is turned on.
0003 Communications with the absolute position detector failed.
0004 Absolute position data for absolute position configuration was changed.
0005 Serial data from the absolute position detector contains an error.
0006 The absolute position does not match the incremental position.
0007 Initial communications with the absolute position detector is disabled.
Check the pulse coder, servo amplifier, axis card and/or cable. Replace or repair as needed and initialize the zero
point after the power is turned on.
Possible Z72 POSITION COLLATION ERROR alarms are as follows:
0001 An error occurred in position collation during G28 or G30 execution.
0002 An error occurred in position collation during M02 or M30 execution.
In both cases if alarm Z71 0003 occurs with this alarm when moving by handle two grids or more, a bad pulse coder is indicated. If Z71 0003 is not present check the allowable value for the alarm. (#4 COLLATION WIDTH on the ABSOLUTE POSITION screen). The setting of this value is dependent upon the machine construction and may be set too low. Try increasing the parameter and cycle power.
Possible Z73 ABSOLUTE POSITION WARNING alarms are as follows:
0001 The backup battery voltage dropped.
Replace the battery.
Most of these alarms may be accompanied by alarm 9F either on the CRT, the servo amplifier or both. In any case it means that the amplifier has detected a drop in the battery voltage.
In some cases where alarm 52 is generated on an M520 control it can be due to the disconnection of the servo motor from the amplifier. This is a normal condition.
After changing certain parameters such as Latch parameters, the NC power may need to be cycled to make the changes effective, of course, but in some cases until the power is cycled the control may become unresponsive. The same thing occurs with Fanuc controls but they will issue alarm 000 to have the power turned off and back on.
Some drives, spindle drives in particular, which use connector CN5 for feedback the two wires for the motor overheat (OSH1 and OSH2) are routed to the amplifier via CN5 so if CN5 is disconnected, alarm S03 SERVO ALARM:NR 0046 (AL-46)will be issued. This is important to know when you are trying to troubleshoot by running the machine in open loop with the connector removed from the amp.
If an M520 control issues alarm S01 003A on an axis the first thing to check for is a shorted motor or motor cable. One thing to be aware of where this over-current alarm is concerned is that due to the way that the military style connector is made (two plastic halves sandwiched together) coolant can get into the connector and cause it to carbonize in turn generating this alarm. In some cases this alarm may come on suddenly or may cause an intermittent condition over a period of time.
AE5 alarm is ABSOLUTE DATA TRANSFER ERROR. It is also associated with an encoder problem.
To troubleshoot alarm S01 PR 0020, swap the feedback cables at the amplifier. You don't have to worry about the axes running away because one of the axes will still be in AL-20 state regardless of the cause.
S02 alarms should show the axis and the parameter where the problem lies. The alarm means that an invalid parameter was sent to the servo amplifier by the NC at power-up. The alarm normally looks like:
S02 INIT. PARAM. ERROR 118 0000
The Y06 alarm is a higher priority alarm than Y03.
S01 SERVO ALARM:PR 0018 A is normal when a rotary table is removed without releasing the axis.
An E6(AL-E6) on an amplifier usually means the machine is in a Not Ready state due to a cause external to the amp.