FANUC Series 16i / 18i / 160i / 180i - Model A. Maintenance Manual (B-63005EN/01)

7. TROUBLESHOOTING

B-63005EN/01

Signal

End state

Finish signal

store signal

b. Travel command is being

CNC is reading an axis command (X,Y,Z,...) in a program and giving the

executed

command to the axis.

c. A dwell command is

CNC is reading a dwell command (G04) in a program and is executing

being executed

the dwell command.

d. In-position check

Positioning (G00) to a specified position of a specified axis is not

(confirming positioning)

completed.

is being done

Whether positioning is completed or not is checked as the servo position

error amount. Check it CNC’s diagnostic function as follows:

DGN no.300

Position Error

> PARAM 1826

In-position width

Position error amount almost becomes 0, when positioning of an axis

completes and when the amount becomes within the in-posiiton width,

it is assumed that positioning completes and the next block is exected.

If position error amount does not become within the in-position width,

refer to servo alarm 400, 4n0 and 4n1.

e. Feedrate override is at

Actual feedrate is overridden by the override signals to a programmed

feedrate. Check the override signals using the PMC’s diagnostic function

(PMCDGN).

G0012

*FV7

*FV6

*FV5

*FV4

*FV3

*FV2

*FV1

*FV0

*FVn

:Feedrate override

<2nd override signal (option)>

Feed rate is overridden more finely using the signals below:

See MTB’s manual whether this feature is equipped.

G0013

*AFV7

*AFV6

*AFV5

*AFV4

*AFV3

*AFV2

*AFV1

*AFV0

*AFVn

:2nd feed rate override

*FV7@@@@@@@*FV0

*AFV7@@@@@@*AFV0

11 1 1 1 1 1 1

11 1 1 1 1 1 0

10 0 1 1 0 1 1

100%

10 0 1 1 0 1 1

100%

00 0 0 0 0 0 1

254%

00 0 0 0 0 0 1

254%

00 0 0 0 0 0 0

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7.TROUBLESHOOTING

Interlock signal or start

lock signal is input

Start lock signal is input

G0007

STLK

#1 (STLK)

With this signal being 1, start lock signal is input.

There are a plural number of interlock functions. Parameters are set by

machine tool builders for which interlock function is used.

Therefore, confirm the following parameters at first:

3003

DIT

ITX

ITL

#0 (ITL)

0 : Interlock signal(*IT) is valid.

#2 (ITX)

0 : Interlock signal (*ITn) is valid.

#3 (DIT)

0 : Interlock signal ("MITn) is valid.

Confirm which interlock signal is activated by the PMC’s diagnostic

function (PMCDGN) .

1) Interlock signal (*IT) is input

G0008

*IT

#0 (*IT)

: When this bit is 0, interlock signal is input.

2) Interlock signal per each axis (*ITn) is input

G0130

*IT8

*IT7

*IT6

*IT5

*IT4

*IT3

*IT2

*IT1

*ITn

When the bit is 0, the corresponding axis’s interlock signal is input.

Interlock signal per axis and direction(+/- MITn) is input

⋅ M series

G0132

+MIT4

+MIT3

+MIT2

+MIT1

G0134

-MIT4

-MIT3

-MIT2

-MIT1

⋅ T series

X0004

-MIT2

+MIT2

-MIT1

+MIT1

"MITn=1 shows interlock signal per axis and direction is input.

* For the T series, "MITn is valid only for manual operation.

Controlled axis detach function is running. A detached axis

specified for travelling.

*This function is valid when CNC parameter No.1005#7=1. For

whether this function is running or not, confirm the following signal

using PMC’s diagnostic function

(PMCDGN). Check the axis

concerned.

F0110

MDTCH8

MDTCH7

MDTCH6

MDTCH5

MDTCH4

MDTCH3

MDTCH2

MDTCH1

When signal MDTHn is “1” ,the axis detach function is in valid.

The control axis detach function becomes valid by the following

signal issued from the PMC or a CNC side parameter. Check as in the

following procedure :

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7. TROUBLESHOOTING

B-63005EN/01

1) The control axis detach signal (DTCHn) is input.

G0124

DTCH8

DTCH7

DTCH6

DTCH5

DTCH4

DTCH3

DTCH2

DTCH1

If it is 1, the corresponding axis is detached.

2) The following parameter enables the control axis detach function to

the corresponding axis.

0012

RMVx

#7(RMVx)0 : Controlled axis is connected

1 : Controlled axis is detached

g. CNC is waiting for

Actual spindle speed does not arrive at a speed specified in a program.

spindle speed arrival

Confirm the signal state using the PMC’s diagnostic function

signal to be input

(PMCDGN).

G0029

SAR

#4(SAR) : When this signal is 0, spindle speed does not arrive at the specified speed.

This function is valid when PARAM 3708#0=1.

h. Manual feedrate override

Normally manual feedrate override function is used for jog feed.

is 0% (dry run)

But when DRN(dry run) signal turns on during an auomatic

operation,override values set with these signals become valid to the

following speed set by a parameter.

G0046

DRN

#7(DRN) : Dry run signal is input with this signal being 1.

1410

Dry run rate

The rate when the following override value is 100%.

G0010

*JV7

*JV6

*JV5

*JV4

+JV3

*JV2

*JV1

*JV0

↓

G0011

*JV15

*JV14

*JV13

*JV12

+JV11

*JV10

*JV9

*JV8

When override value is 0%, all bits of the above address is

[1111

1111] or [0000

. . . . 0000].

*JV15 .

JV0

Override

1111 1111 1111 1111

0.00%

1111 1111 1111 1110

0.01%

1101 1000 1110 1111

100.00%

0000 0000 0000 0001

655.34%

0000 0000 0000 0000

0.00%

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7.TROUBLESHOOTING

i. NC is in a reset state

In this case, the CNC’s status display shows RESET. Refer to item 1.

(2) Only rapid traverse in positioning (G00) does not function Confirm

the following parameter and signals from the PMC.

(a) Setting value of rapid traverse rate

1420

Rapid traverse rate per axis

(b) Rapid traverse override signals

G0014

ROV2

ROV1

G0096

HROV

*HROV6

*HROV5

*HROV4

*HROV3

*HROV2

*HROV1

*HROV0

(HROV-0)

(HROV=1)

ROV1

ROV2

Override

*HROV6

*HROV0

Override

100%

1 1

50%

1 1

25%

0 0

100%

1421

Rapid traverse override F0 rate

(3) Only feed (other than G00) does not function

(a) Maximum feedrate set by parameter is incorrect.

1422

Maximum feedrate

Feedrate is clamped at this upper feedrate.

(b) Feedrate is specified by feed per revolution (mm/rev)

1) Position coder does not rotate

Check the connection between spindle and position coder

The following failure is considered:

⋅

T iming belt is broken

⋅

Key is removed

⋅

Coupling is loose

⋅

Connector of signal cable is loosened

2) Position coder is faulty

1) Position coder does not rotate

Check the connection between spindle and position coder

The following failure is considered:

⋅

Timing belt is broken

⋅

Key is removed

⋅

Coupling is loose

⋅

Connector of signal cable is loosened

2) Position coder is faulty

Position coder is connected to the spindle amplifier when serial

interface spindle is used or connected to the CNC when analog

interface spindle is used.

For details of connection, refer to the following.

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7. TROUBLESHOOTING

B-63005EN/01

Whether A/B phase signals from the position coder are read

correctly, can be judged also by the spindle speed display on the

CRT screen (position screen). (However, it is not displayed

when PARAM 3105#2=0).

<α series spindle amplifier>

Position

CNC

coder

JA7B

JY2

JA41

SPM

JA7A

TB2

Spindle

motor

Position

coder

JA7B

JY2

SPM

Spindle

JA7A

TB2

motor

CNC

JA41

Position

coder

Analog spindle

Spindle

JA40

amplifier

motor

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B-63005EN/01

7.TROUBLESHOOTING

7.6

CYCLE START LED

SIGNAL HAS TURNED

OFF

Points

(1) After cycle operation is started, then stopped, check as follows:

(2) Confirm cycle start LED on machine operator’s panel.

(3) Confirm CNC’s diagnostic function.

Causes and Remedies

The reason why cycle start LED signal (STL) has turned off are displayed

on CNC’s diagnostic numbers 020 to 025 as follows:

020 CUT SPEED UP/DOWN

021 RESET BUTTON ON 0

022 RESET AND REWIND ON

023 EMERGENCY STOP ON

024 RESET ON

025 STOP MOTION OR DWELL

a. Emergency stop signal

b. External reset signal

c. Reset button on MDI

d. Reset & rewind signal

e. Servo alarm

Feed hold by switching mode

g. Single block stop

Details of signals a to g are as follows:

Confirm the signals concerned using diagnostic function (PMCDGN).

a. Emergency stop is input

1) When I/O card is used :

X1008

*ESP

G0008

*ESP

*ESP=0

: Emergency stop signal is input :

2) When I/O card is not used:

X0008

*ESP

G0008

*ESP

*ESP=0

: Emergency stop signal is input :

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7. TROUBLESHOOTING

B-63005EN/01

b. External reset signal is

input

G0008

ERS

#7(ERS) :

When the bit is 1, external reset signal is input.

This signal is usually used for a confirmation signal of M02 when an M02

is specified in a program as the end of a program.

Therefore, when M02 is executed, this signal is input.

c. Reset button on the MDI

An automatic operation is put into a reset status when RESET key on the

is pressed

MDI panel is pressed.

d. Reset & rewind signal is

input

G0008

RRW

#6(RRW) :

When this signal is 1, the reset & rewind signal is input.

This signal is usually used for a confirmation signal of M30 when an M30

is specified in a program as the end of a program.

Therefore, when M30 is executed, this signal is input.

e. Servo alarm has

When any servo alarm has generated, cycle operation is put into the reset

generated

state and operation stop.

Cycle operation is in a

The cycle operation becomes feed hold state in the following cases:

feed hold state

1) Modes are switched from an automatic operation mode to a manual

operation mode.

2) Feed hold signal is input.

G0043

MD4

MD2

MD1

memory edit(EDIT)

Automatic

Automatic operation

operation

(AUTO)

Manual data input (MDI)

Jog feed (JOG)

Manual

Handle/step

operation

TEACH IN HANDLE

TEACH IN JOG

G0008

*SP

#5(*SP) : When this signal is 0, the feed hold signal is input.

g. It become single block

stop during automatic

operation

G0046

SBK

#1(SBK) When this signal is 1, the single block signal is input.

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B-63005EN/01

7.TROUBLESHOOTING

7.7

NO DISPLAY

APPEARS AT

POWER-UP

Points

Check whether this problem is caused by (1) a trouble in the display

system or (2) a system failure.

Determining the point

Check that the LEDs on the motherboard are in the status shown below.

For Series 16i/18i

(

:On

:Off )

Rear of the unit

JD36A

CA55

CA54

CP1A

CP1B

LED

LED1

LED2

LED3

LED4

STATUS (green)

SERVO

SYSEMG

SYSFAIL

PARITY

ALARM (orange)

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7. TROUBLESHOOTING

B-63005EN/01

For Series 160i/180i with a personal computer function

(

: On

: Off

)

LED positions

Rear of the unit

JD33

CA54

CA55

LED

STATUS(green)

ALARM (orange)

If the LED status indicated above is observed, the system operates

normally. In this case, there is a trouble in the display system.

If the LEDs are not in the status indicated above, there is a trouble in

hardware other than the display system.

Causes and

countermeasures

1. When the display system

(1) Check the following:

is in trouble

1) Is the power cable of the backlight connected?

2) Is the video signal cable connected? Is there cable breakage or poor

contact?

(2) Causes and remedies

When nothing is displayed

1) The power supply to the display is faulty.

(Replace the

motherboard or inverter PC board.)

2) The display is faulty.

2. When the system is in

When the LEDs on the motherboard are not in the status indicated in

trouble

”Determining the point” given previously, the motherboard or display

control card may be faulty.

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B-63005EN/01

7.TROUBLESHOOTING

7.8

ALARM 85 TO 87

(READER/PUNCHER

(START)

INTERFACE ALARM)

YES

Alarm 85?

· Check baud rate

and other I/O pa

rameters

YES

· I/O device is

Alarm 86?

faulty

Is I/O

parameter

correct?

YES

Set correct parameters

OFF

Is power of I/O ?

Turn on I/O device

Is cable

connection right?

YES

Connect the cable

· I/O device is faulty

· I/O interface

module is faulty

Alarm 87

· I/O device is faulty

· I/O interface mod

ule is faulty

Causes

(a) Parameters on reader/puncher interface are not correct.

Check the following setting data and parameters.

(b) External I/O device or host computer is faulty.

(d) Cable between NC and I/O device is faulty.

Countermeasures

(a) Parameters on reader/puncher interface are not correct.

Check the following setting data and parameters:

PUNCH CODE=0 OR 1 (0: EIA,1:ISO)

Select ISO or EIA according to the type of I/O device.

If punch code does not match, alarm 86 will generate.

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7. TROUBLESHOOTING

B-63005EN/01

Value of parame-

ter 0020

Function

Feed

0101#7

0111#7

0121#7

0131#7

Data input code

0101#3

0111#3

0121#3

0131#3

Stop bit

0101#0

0111#0

0121#0

0131#0

Type of I/O device

102

112

122

132

Baud rate

103

113

123

133

Commu-

0135#3

nication

method

RS-232C

RS-422

MAIN CPU BOARD

OPTION-1 BOARD

Connector

JD5A

JD5B

JD5C

JD6A

Numbers in the table indicate parameters and bit numbers.

Example)

101#7:bit7 of parameter 101.

NOTE

For data communications by RS-422, refer to parameters

134 and 135.

0101

NFD

ASI

SB2

0111

0121

0131

#7(NFD)

0 : Feed is output before and after data in data output (FANUC PPR)

1 : Feed is not output (standard).

#3(ASI)

0 : Data input code is EIA or ISO (automatic recognition)

1 : Data input code is ASCII.

#0(SB2)

0 : No. of stop bits is 1.

1 : No. of stop bits is 2.

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7.TROUBLESHOOTING

0102

Type of I/O device

0112

0122

Value

TYPE OF I/O DEVICE

0132

RS-232-C (control codes DC1 to DC4 are used)

FANUC CASSETTE B1/B2 (bubble cassette)

FANUC CASSETTE F1 (Old type FLOPPY CASSETTE ADAP-

TOR)

FANUC PROGRAM FILE Mate,

FANUC FA CARD ADAPTOR

FANUC FLOPPY CASSETTE ADAPTOR,

FANUC SYSTEM P-MODEL H,

FANUC Handy File

Not used

Portable tape reader

FANUC PPR, FANUC SYSTEM P-MODEL G,

FANUC SYSTEM P-MODEL H

0103

Baud rete

0113

0123

Value

Baud rate

4800

0133

600

9600

1200

19200

2400

When bit#3 of parameter no. 0135=1 (RS-422 interface), the following

setting is also available.

Value

Baud rate

38400

76800

86400

Check the following parameters also, when parameter no.0020 is 3.

0134

CLK

NCD

SYN

PRY

#5(CLK)

0 : Internal clock is used for baud rate clock of RS-422 interface.

1 : External clock is used for baud rate clock of RS-422 interface.

#4(NCD)

0 : CD (signal quality detection) of RS-232C interface is checked.

1 : CD (signal quality detection) of RS-232C interface is not checked.

#2(SYN)

0 : In protocol B, NC reset/alarm is not informed to the host.

1 : In protocol B, NC reset/alarm is informed to the host by SYN and

NAK code.

#1(PRY)

0 : No parity bit

1 : With parity bit

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7. TROUBLESHOOTING

B-63005EN/01

0135

RMS

R42

PRA

ETX

ASC

#7(RMS) In protocol A, status of remote / tape operation of SAT command is

0 : Always transmitted by 0.

1 : Transmitted by the contents of remote / tape switching request issued

by SET command from the CNC.

#3(R42)

0 : Interface is of RS-232C.

1 : Interface is of RS-422.

#2(PRA)

0 : Communication protocol is protocol A

1 : Communication protocol is protocol B

#1(ETX)

0 : End code of protocol A or extended protocol A is CR of ASCII/ISO.

1 : End code of protocol A or extended protocol A is ETX of ASCII/ISO.

#0(ASC)

0 : All the communication codes except for NC data is ISO code.

1 : All the communication codes except for NC data is ASCII code.

(b) External I/O device or Host computer is in trouble

(i)

Check whether the setting on communication of external I/O

device or host computer is the same as that of the CNC. (baud

rate, stop bits,etc.) If they are not the same, change the setting.

(ii)

When spare I/O device presents, check whether it is possible to

realize communication using the spare I/O device.

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B-63005EN/01

7.TROUBLESHOOTING

(i)

When parameter no.0020 is 0 or 1 or 2 (JD36A,JD36B of Main

CPU board) Replace the module since spindle module may be

faulty.

(ii)

When parameter no. 0020 is 3 (JD28A,JD6A of option 1 board)

Because communication control module (5) may be faulty,

replace the module.

(d) Cable between NC and I/O device is faulty.

Check the cable for disconnection or wrong connection.

Mother board

R232C(JD36A)

Punch panel

R232C(JD36B)

Tape reader

Serial

communication

R232C(JD28A)

Host computer

R232C(JD6A)

Host computer

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7. TROUBLESHOOTING

B-63005EN/01

< Cable connection>

R232C

(JD36A)

Punch panel

R232C

(JD36B)

(01)

(03) RD

(02)

(03)

(06) DR

(04)

(05)

(05) CS

(06)

(07)

(08) CD

(08)

(09)

+24V (10)

(11)

(02) SD

(12)

(13)

(20) ER

(14)

(15)

(04) RS

(16)

(07) SG

(17)

(18)

+24V (19)

(25) +24V

(20)

(01) FG

Shield

Connector :DBM-25S

Connector : Half-pitch 20-pins

R232C

(JD28A)

Host computer

(01)

(02) SD

(02)

(03)

(20) ER

(04)

(05)

(04) RS

(06)

(07)

(08) CD

(08)

(09)

+24V (10)

(11)

(03) RD

(12)

(13)

(06) DR

(14)

(15)

(05) CS

(16)

(07) SG

(17)

(18)

+24V (19)

(25) +24V

(20)

(01) FG

Shield

Connector D-SUB 25 pins

Connector : Half-pitch 20-pins

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B-63005EN/01

7.TROUBLESHOOTING

CAUTION

When CS is not used, connect it to RS.

For protocol A or extended protocol A: When DR is not used,

connect it to ER. Always connect CD to ER.

RS422(JD6A)

Host computer

RD (01)

(04) RD

*RD (02)

(22) *RD

RT (03)

(17) TT

*RT (04)

(35) *TT

CS (05)

(07) RS

*CS (06)

(25) *RS

DM (07)

(12)

Note) *DM (09)

(30) *TR

0V (08)

(19) SG

(+24V) (10)

SD (11)

(06) RD

*SD (12)

(24) *RD

TT (13)

(08) RT

*TT (14)

(26) *RT

RS (15)

(09) CS

*RS (16)

(27) *CS

TR (17)

(11) DM

*TR (18)

(29) *DM

(+24V) (19)

(20)

(01) FG

Shield

Connector : Half-pitch 20 pins (PCR)

Connector : D-SUB 25 pins

CAUTION

Always use a twisted pair cable.

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7. TROUBLESHOOTING

B-63005EN/01

7.9

ALARM 90

(REFERENCE

POSITION RETURN IS

ABNORMAL)

Contents

Reference position return was executed when the following condition is

not satisfied:

The CNC received one rotation signal at least one time when the axis is

moving to the reference position at a speed higher than a speed equivalent

to 128 pulses of position error amount(DGN300).

Countermeasures

(START)

Position error

Check whether position gain is greater than 128 pulses

amount : 300

(DGN 300) before or during reference position return.

YES

128 or more

(1) Next page

Raise the speed

Check feed rate command:

PRM 1420 F : Rapid traverse rate

(mm/min)

PRM 1424

Manual rapid traverse rate (mm/min)

PRM 1825 G : Servo loop gain

(0.01sec-1)

5000/3

Position error=

G detection unit[µm/PLUSE]

Detection unit : Move amount to a command pulse (usually 1µm)

In metric machine, if the no. of digits below decimal point is 4 on the position

display screen, detection unit is 0.1 mm.

Check rapid traverse override signals :

ROV1

DGN

014.0

ROV1

ROV2

Override

1014.0 (For TT series)

ROV2

DGN

014.1

100%

1014.1 (For TT series)

50%

PRM

1421

Fo rate

25%

Fo rate

Check reference position return deceleration signal

DEC1 DEC8 DGN 009.0 ∼ 009.7

When reference position return is started from deceleration signal 0, feed rate

becomes FL rate.

PRM 1425 FL rate

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B-63005EN/01

7.TROUBLESHOOTING

(1)

Check whether the motor ratated more than one rota-

tion (one rotation signal is issued ) at faster than 128

pulses of position error amount.

Return start position is too close

Rotated ?

· Chagne the return start position.

· Move the machine at faster that 128

YES

pulses for more than one rotation to

wards RP.

Check that voltage of pulse coder is higher than 4.75 V.

To measure pulse coder voltage, remove the motor cover and measure on

pulse coder PCB at across + and - or +5V and 0V terminals.

More than 4.75V

YES

Hardware failure

Pulse coder power voltage is low

· Pulse coder is faulty

· Caused by wire resistance

Change pulse coder or motor

check wire material

· Main CPU board is faulty

(resistance shall be 0.5W or

Change main CPU board

less in both ways to restrict

· Option 2 board is faulty

voltage drop.)

Change option 2 board

· Pulse coder power supply is

abnormal

Change the power supply .

CAUTION

After the pulse coder or motor is exchanged, reference

position or machine’s standard point may be different from

former one. Please set it correctly.

When the main board is exchanged, all the data stored in

memory is lost. Reset all the NC data again, referring to the

data input/output item.

D Reference

A speed more than 128 pulses is required because if speed is lower that

this, one-rotation signal does not function stably, causing improper

position detection.

If bit 0 of parameter No. 2000 is set to 1, a speed corresponding to a

positional deviation of 1280 pulses or more is required.

Parameter No. 1836 can be set to 128 or less, as the minimum positional

deviation with which reference position return is possible.

(If the

parameter is set to 0, 128 is assumed as the minimum positional deviation.

If bit 0 of parameter No. 2000 is set to 1, a value equal to ten times the

set value is used for checking.)

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7. TROUBLESHOOTING

B-63005EN/01

Absolute position data in the serial pulse coder was lost.

7.10

(This alarm will be generated when serial pulse coder is exchanged or

ALARM 300

position feedback signal cable of the serial pulse coder is disconnected).

(REQUEST FOR

REFERENCE

POSITION RETURN)

Remedies

Machine position must be memorized using the following method:

D When reference position

(1) Execute manual reference position return only for an axis for which

return function is

this alarm was generated.When manual reference position return

present

cannot be executed because of an another alarm, set parameter 1815#5

to 0 and release the alarm and perform manual operation.

(2) Press RESET key at the end of reference position return to release the

alarm.

D When reference position

Execute dogless reference position setting to memorize the reference

return function is not

position.

present

D When serial pulse coder

Since the reference position is different from the former one, change the

is changed

grid shift value (PRM 1850) to correct the position.

Related parameters

1815

APC x

APZx

#5(APCx)

0 : Position detector is incremental pulse coder.

1 : Position detector is absolute pulse coder.

#4(APZx)

Reference position of absolute pulse coder is :

0 : not established

1 : established

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7.TROUBLESHOOTING

Digital servo parameters are abnormal.

7.11

(Digital servo parameters are set incorrectly.)

ALARM 417 (DIGITAL

When alarm 315 is occured at the same time, check the cause of alarm 351

SERVO SYSTEM IS

of section 9.16.

ABNORMAL)

D Causes

Confirm the setting value of the following parameters:

PRM 2020 : Motor format number

PRM 2022 : Motor rotation direction

PRM 2023 : Number of pulses of velocity feedbacks

PRM 2024 : Number of pulses of position feedback

PRM 1023 : Servo axis number

PRM 2084 : Flexible feed gear ratio

PRM 2085 : Flexible feed gear ratio

Confirm the details with diagnosis function of CNC side.

Change the setting of this parameter to 0.

PRM 2047 : Observer parameter

Perform initial setting of digital servo parameters.

Refer to setcion 5.1 “Initial Setting of Servo Parameters” .

This data indicates the cause of servo alarm No. 417, detected by the NC.

If the alarm is detected by the servo, the PRM bit (bit 4 of DGN No. 0203)

is set to 1.

0280

AXS

DIR

PLS

PLC

MOT

#0(MOT) :

The motor type specified in parameter No. 2020 falls outside the

predetermined range.

#2(PLC) :

The number of velocity feedback pulses per motor revolution, specified in

parameter No. 2023, is zero or less. The value is invalid.

#3(PLS) :

The number of position feedback pulses per motor revolution, specified in

parameter No. 2024, is zero or less. The value is invalid.

#4(DIR) :

The wrong direction of rotation for the motor is specified in parameter No.

2022 (the value is other than 111 or -111).

#6(AXS) :

In parameter No. 1023 (servo axis number), a value that falls outside the

range of 1 to the number of controlled axes is specified. (For example, 4 is

specified instead of

3.)

Alternatively, the values specified in the

parameter are not consecutive.

339

7. TROUBLESHOOTING

B-63005EN/01

Spindle speed changes abnormally due to load.

7.12

ALARM 704 (SPINDLE

SPEED

FLUCTUATION

DETECTION ALARM)

Remedies

Check whether spindle speed is constant by view

of the speed meter on CRT.

YES

Constant ?

Is a heavy cutting being per-

formed ? Confirm spindle load

on CRT.

Confirm the follow-

ing parameter :

YES

Heavy cutting?

PRM 4911

PRM 4912

PRM 4913

Reduce cutting condition

PRM 4914

Doesn’t the cutting tool worn ?

YES

Worn ?

Replace tool

Spindle servo unit is faulty

Spindle motor is faulty

Remedies

PRM 4911 : A ratio of spindle speed at which actual spindle speed is

regarded as arrived at a command spindle speed.

PRM 4912 : Spindle speed fluctuation ratio up to which the spindle

speed fluctuation detection alarm is not issued.

PRM 4913 : Spindle speed fluctuation that is not regarded as the spindle

speed fluctuation alarm.

PRM 4914 : Time when a spindle speed changed to when spindle speed

fluctuation detection is started.

340

B-63005EN/01

7.TROUBLESHOOTING

Communication error has generated in serial spindle

7.13

ALARM 749

(SERIAL SPINDLE

COMMUNICATION

ERROR)

Causes and Remedies

Improper connection between the mother board and the serial spindle.

The following reason is considered.

Main

CPU

ROM

Optical I/O link

adaptor

Spindle

RAM

Spindle control

amplifier

Optical cable

System control module is faulty. (Bold line in the figure below indicates

module mounting position.)

A cable between the mother board and optical I/O link adapter is

disconnected or short-circuited.

Optical I/O link adapter is faulty.

Optical cable is disconnected.

Serial spindle amplifier is faulty.

341

7. TROUBLESHOOTING

B-63005EN/01

When the spindle amplifier does not become normal state immediately

7.14

after power is turned on in the serial spindle system, this alarm is

ALARM 750 (SPINDLE

informed.

SERIAL LINK

CANNOT BE

STARTED)

Points

This alarm does not occur once the system becomes ready including the

spindle system .

This alarm occurs during power on sequence before the system becomes

ready.

After the system becomes ready, serial spindle alarm is issued by alarm

749.

Causes

(1) Optical cable is in poor contact or spindle amplifier power is off.

(2) When display of spindle amplifier shows SU-01 or an alarm other than

AL-24 is displayed, power to the NC is turned on.

In this case, this alarm usually occurs when the NC’s power is turned

off while the serial spindle is operating. Turn off the power of serial

spindle once, then turn it on and starts the system.

(3) Combination of hardware is wrong.

(4) When the 2nd spindle is at the state of (1) to (3).

When the 2nd spindle is used, parameter is set as follows :

Bit 4 of parameter no.3701 is 1: No. of serial spindles connected is 2.

Details of Alarms

Confirm the details of troubles on diagnostic 409.

DGN

0409

SPE

S2E

S1E

SHE

#3(SPE)

0 : In spindle serial control, the serial spindle parameters satisfies the

starting conditions for spindle amplifier.

1 : In spindle serial control, the serial spindle parameters do not satisfy

the starting conditions for spindle amplifier.

#2(S2E)

0 : At the start of spindle serial control, the spindle is normal.

1 : At the start of spindle serial control, the spindle is abnormal.

#1(S1E)

0 : The serial communication module of the CNC side is normal.

1 : The serial communication module of the CNC side is abnormal.

#0(SPE)

0 : Serial communication module on the CNC side is normal.

1 : Serial communication module was detected to be abnormal on the

CNC side.

342

B-63005EN/01

7.TROUBLESHOOTING

Remedies

Reform the following countermeasures based on the above

configurations:

(1) #3(SPE)1: In spindle serial control, the serial spindle parameters does

not satisfy the starting conditions for spindle amplifier.

↓

Confirm the settings of parameters 4000s.

Especially checks the parameters those are changed from the standard

parameters.

(2) #2(S2E)1: At the start of spindle serial control, when an abnormality

is found in the 2nd spindle side.

↓

Check the 2nd spindle parameters and connections to see whether the

spindle is mechanically and electronically connected to the spindle.

↓

If the above settings and connections are right, the module of (4) or the

spindle amplifier itself may be defective.

(3) #1(SIE)1: When an abnormality is found in the 1st spindle at the start

of serial spindle control, exchange the unit if the following

check items are not concerned.

↓

Check the parameters and connections at the 1st spindle to see whether

the 1st spindle is mechanically and electrically connected.

↓

If the parameters and connections are correct, the system control

module shown below or the spindle amplifier itself is faulty.

(4) #0(SPE)1: The serial communication module is detected to be

abnormal. Exchange the following module :

343

7. TROUBLESHOOTING

B-63005EN/01

Because an ambient temperature of the control unit becomes high, a

7.15

thermostat mounted on the back panel of NC functions and informs an

ALARM 700

alarm.

(OVERHEAT AT

CONTROL SIDE)

Remedies

(START)

Check fan on the top of the control unit is oper-

ating when power is on.

Operating

YES

Check temperature around the control unit is

Fun motor is faulty

high (more than 45 degrees)

Replace fan motor

YES

High tempera-

ture ?

Thermostat on the back panel of NC

Lower temperature around

is faulty.

the control unit

Replace the back panel of NC.

344

B-63005EN/01

7.TROUBLESHOOTING

ROM parity error occurred.

7.16

ALARM 900 (ROM

PARITY ERROR)

Causes and Remedies

(1) ROM module mounted on the mother board or ROM is defective.

SYSTEM ALARM

B0A1-02

900

ROM PARITY

CNC ROM MODULE : FC0

Defective file

or ROM is displayed

MACRO ROM MODULE

SERVO ROM

Confirm the series and versions of control software those are displayed

on upper right of the screen.

*FROM module may be written data by machine tool builder.

345

B-63005EN/01

7.TROUBLESHOOTING

A parity error occurred in the RAM module for workpieces.

7.17

ALARM 910, 911

(SRAM PARITY

ERROR)

Causes and

countermeasures

D SRAM module is faulty.

If the alarm is issued immediately after the power is turned on, turn off

Stored data is faulty.

the power, then turn it on while holding the

RESET

and

DELETE

keys to clear

all memory contents.

If the parity alarm still exists even after the memory all clear operation,

the SRAM module on the motherboard may be faulty. So, replace the

SRAM module.

D Set all data again according to ”Data Input/Output”.

D Voltage drop in the

A battery alarm is issued if the voltage level drops to 2.6 V or lower when

memory backup battery

the voltage rating is 3.0 V.

When the voltage of the memory backup battery has lowered, ”BAT”

blinks at the bottom of the screen.

When the battery alarm is turned on, replace the battery with a new lithium

battery as soon as possible.

D Replace the battery according to Section 2.9.

D The motherboard is

If the alarm is released by memory all clear operation, the motherboard

faulty.

may also be faulty.

NOTE

If an SRAM parity alarm occurs in a module other than the

motherboard, ALM972 NMI OCCURRED IN OTHER

MODULE appears.

If a parity alarm occurs in a system that has been kept

switched off for a long time, it is likely that the battery life has

expired or the backup circuit

(on the motherboard) is

defective.

347

B-63005EN/01

7.TROUBLESHOOTING

A parity error occurred in the DRAM module.

7.18

ALARM 912 TO 919

(DRAM PARITY

ERROR)

Cause and

The DRAM module on the CPU card may be faulty. Replace the DRAM

countermeasure

module.

D Mounting position of the

DRAM module

The DRAM module is mounted

on the CPU card.

Remove the CPU card accord-

ing to Section 2.6.

(1)

(2)

(3)

Axis control card

Display control card

CPU card

Motherboard

DRAM module

Connector

DIMM module socket

Side B of CPU card

349

FANUC Series 16i / 18i / 160i / 180i - Model A. Maintenance Manual (B-63005EN/01) - page 12