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FANUC Series 30i/300i/300is-MODEL A. Machining Center System. User's manual - page 35

PROGRAMMING

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9. SPINDLE SPEED FUNCTION

(S FUNCTION)

9.5

SPINDLE SPEED FLUCTUATION DETECTION

Overview

With this function, an overheat alarm (OH0704) is raised and the
spindle speed fluctuation detection alarm signal SPAL is issued when
the spindle speed deviates from the specified speed due to machine
conditions.
This function is useful, for example, for preventing the seizure of the
guide bushing.
G26 enables spindle speed fluctuation detection.
G25 disables spindle speed fluctuation detection.

Format
- Spindle fluctuation detection on

G26 Pp Qq Rr Ii

；

P: Time (in ms) from the issue of a new spindle rotation

command (S command) to the start of checking whether
the actual spindle speed is so fast that an overheat can
occur.

When a specified speed is reached within the time period

of P, a check is started at that time.

Q: Tolerance (%) of a specified spindle speed

100

−

speed

spndle

specified

speed

spindle

actual

If a specified spindle speed lies within this range, it is

regarded as having reached the specified value. Then,
the checking of an actual spindle speed is started.

R: Spindle speed fluctuation (%) at which the actual spindle

speed is so fast that an overheat can occur

100

−

speed

spndle

speciofied

overheat

cause

can

that

speed

If the fluctuation of the actual spindle speed to the

specified spindle speed exceeds the spindle speed
fluctuation of R, the actual spindle speed is regarded as
being so fast that an overheat can occur.

I: Spindle speed fluctuation width at which the actual

spindle speed (min

-1

) is so fast that an overheat can

occur

If the fluctuation (width) between the specified and

actual spindle speeds exceeds the spindle speed
fluctuation width of I, the actual spindle speed is
regarded as being so fast that an overheat can occur.

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9.SPINDLE SPEED FUNCTION

(S FUNCTION)

G26 enables the spindle speed fluctuation detection function. The
values specified for P, Q, R, and

are set in the following parameters:

No. 4914, No. 4911, No. 4912, and No. 4913, respectively. Each
command address corresponds to a parameter number as listed below.

Command address

Parameter number

Q No.4911
R No.4912

I No.4913

P No.4914

If the P, Q, R, or I command address is omitted, the function detects
the fluctuation of the actual spindle speed according to the value set in
the corresponding parameter (No. 4914, No. 4911, No. 4912, or No.
4913).
The parameters (No. 4914, No. 4911, No. 4912, and No. 4913) for the
spindle on which the currently selected position coder is mounted are
used for the setting and spindle speed fluctuation detection check.

- Spindle fluctuation detection off

G25;

G25 disables the spindle speed fluctuation detection function.
When G25 is specified, the parameters (No. 4914, No. 4911, No. 4912,
and No. 4913) are unchanged. When the power is turned on or after
a reset (clear state (bit 6 (CLR) of parameter No. 3402 = 1)) is
executed, the spindle speed fluctuation detection function is disabled
(G25). For the clear state, also check the setting of bit 3 (C19) of
parameter No. 3408 for the M series or bit 0 (C08) of parameter No.
3407 for the T series.

Explanation

The function for detecting spindle speed fluctuation checks whether
the actual speed varies for the specified speed or not. Si or Sr,
whichever is greater, is taken as the allowable fluctuation speed (Sm).
An alarm (OH0704) is activated when the actual spindle speed varies
for the commanded speed (Sc) under the condition that the variation
width exceeds the allowable variation width (Sm).

|Sc – Sa| > Sm

Sc : Specified spindle speed
Sa : Actual spindle speed
Si

: The allowable constant variation width which is

independent of the specified spindle speed (parameter
(No.4913))

Sr : The allowable variation width which is obtained by

multiplying Sc (commanded spindle speed) by r (constant
ratio). (r = parameter (No.4912))

Parameter FLR(No.4900#0)= 0

Parameter FLR(No.4900#0)= 1

100

1000

Sm: Si or Sr, whichever is greater

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9. SPINDLE SPEED FUNCTION

(S FUNCTION)

- Conditions to start spindle speed fluctuation detection

If the specified spindle speed Sc changes, spindle speed fluctuation
detection starts when one of the conditions below is met:

<1> The actual spindle speed falls in a range of (Sc - Sq) to (Sc + Sq)

Sc : Specified spindle speed
Sq : Tolerance within which the spindle is assumed to attain the

programmed speed
(parameter (No.4911))

Parameter FLR= 0

Parameter FLR= 1

100

1000

<2> When time p specified in parameter No. 4914 elapses after the

specified speed Sc changes.

- Examples of spindle speed fluctuation detection

(Example 1)

When an alarm (OH0704) is issued after a specified spindle
speed is reached

Spindle

speed

Specified

speed

Actual

speed

Time

Alarm

Start of check

Specification of

another speed

CHECK

NO CHECK

CHECK

G26 mode

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9.SPINDLE SPEED FUNCTION

(S FUNCTION)

(Example 2)

When an alarm OH0704 is issued before a specified spindle
speed is reached

Spindle

speed

Specified

speed

Actual

speed

Time

Alarm

Start of

check

Specification of

another speed

CHECK

NO CHECK

CHECK

G26 mode

Specified speed :
(Speed specified by address S and five-digit value)

(spindle

override)

Actual speed : Speed detected with a position coder
p : Period after a change occurs in the actual spindle speed until

detection starts
Parameter No.4914, address P

Sq : (Specified spindle speed)

(Detection start tolerance (q))

Parameter No.4911, address Q

Parameter FLR = 0

Parameter FLR = 1

100

1000

Sr : (Specified spindle speed)

(Allowable variation (r))

Parameter No.4912, address R

Parameter FLR = 0

Parameter FLR = 1

100

1000

Si : Allowable variation width

Parameter No.4913, address I

If the difference between the specified speed and actual speed exceeds
both Sr and Si, an alarm OH0704 is raised.

- Relationship between spindle speed control and each spindle

Serial spindle

Spindle

Function

1st spindle 2nd spindle 3rd spindle 4th spindle

Spindle speed

fluctuation detection

Possible Possible

(*1)

Possible

(*1)

Possible

(*1)

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9. SPINDLE SPEED FUNCTION

(S FUNCTION)

NOTE

1 An optional function of multi spindle control is

necessary.

2 The spindle speed fluctuation detection function is

effective for a single spindle. The function cannot be
executed for two or more spindles.

The spindle speed fluctuation detection function is
effective for a spindle on which the currently selected
position coder is mounted.    Just a single position
coder can be selected.    Multiple position coders
cannot be selected.    For the selection of a position
coder, see the section of "Multi spindle."

* Position coder selection signals

(PC2SLC<Gn028.7>, PC3SLC<Gn026.0>,
PC4SLC<Gn026.1>)

3 The parameters that become valid are the parameters

of the spindle speed fluctuation detection function
(No.4911, No.4912, No.4913, No.4914) for the
spindle on which the currently selected position coder
is mounted.

- Spindle for which to detect the spindle speed fluctuation

For the spindle for which to detect the spindle speed fluctuation, refer
to the appropriate manual provided by the machine tool builder.

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9.SPINDLE SPEED FUNCTION

(S FUNCTION)

9.6

SPINDLE CONTROL WITH SERVO MOTOR

9.6.1

Spindle Control with Servo Motor

- Command with a program

This function provides SV speed control mode in which spindle
rotation commands, S commands, are effective to a rotation axis with
a servo motor and position control mode in which normal positioning
can be performed.    To place a servo motor under speed control, you
must turn SV speed control mode ON (G96.4). Once SV speed
control mode is turned ON,
S commands are effective to the servo motor until it is canceled.
You cannot specify positioning commands while SV speed control
mode is ON.  To perform positioning, you must cancel SV speed
control mode.
To cancel SV speed control mode (turn position control mode ON),
you must specify a spindle indexing command, G96.1/G96.2.
In position control mode, S commands are invalid as in the normal
servo axis state.    Note, however, S command information is stored;
when SV speed control mode is ON, rotation starts at the already
specified speed.

- Command with a signal

You can also turn SV speed control mode ON/OFF with the SV speed
control mode signal (Gn521).  When you turn SV speed control
mode ON with the signal, and if you turn SV speed control mode OFF
with a program command, you must specify the SV speed control
mode signal or specify G96.4 to turn SV speed control mode ON
again.    You can check the state of SV speed control mode with the
SV speed control mode in-progress signal (Fn521).    When you turn
SV speed control mode signal OFF while rotating, spindle indexing is
executed.  Then SV speed control mode is turned off. Spindle
indexing is executed with R0(absolute position 0).

Format

G96.4 P_ ;

SV speed control mode ON

M03 (M04) S_ P_ ;

Rotation command

S: Spindle speed [min

-1

] (numeric value of up to five digits)

P: Spindle selection with multi-spindle control

Using G96.4 and a spindle selection command P can turn the SV
speed control mode ON for each axis separately. Likewise, using a
spindle indexing command (G96.1/G96.2) and a spindle selection
command P can cancel the SV speed control mode, that is, turn on the
position control mode ON, for each axis separately.
To specify “G96.4 P_ ;”, use an independent block.
However, it is possible to specify "G96.4 P_ S_ ;".

PROGRAMMING

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9. SPINDLE SPEED FUNCTION

(S FUNCTION)

9.6.2

Spindle Indexing Function

Format

G96.1 P_ R_ ;

After spindle indexing is completed, the
operation of the next block is started.

G96.2 P_ R_ ;

Before spindle indexing is completed,
the operation of the next block is
started.

G96.3 P_ ;

After it is confirmed that spindle
indexing is completed, the operation of
the next block is started.

P: Spindle selection with multi-spindle control
R: Stoppage angle [deg] (0 to (parameter No. 1260))

To specify address P, use parameter No. 3781 (P code for selecting a
spindle in multi-spindle control).
To turn the position control mode ON without performing spindle
indexing, do so after canceling the SV speed control mode by issuing
a G96.1 command with no R specified when the motor is at a halt.
When the motor is rotating, issuing a G96.1 (or G96.2) command with
no R specified results in the motor coming to a halt by behaving in the
same manner as for R0.

NOTE

1 When using G96.2, issue G96.3 before another

spindle move command, to make sure that the
spindle is at a complete halt.

2 To issue G96.1, G96.2, or G96.3, use an

independent block.

Spindle indexing command
- Move command

(1) Command waiting for spindle indexing to be completed

If G96.1 is issued, the next block is executed after spindle
indexing is completed.

(2) Command not waiting for spindle indexing to be completed

If G96.2 is issued, the next block can be executed before spindle
indexing is completed.

- Movement completion check command

G96.3 is used to check to see if spindle indexing is completed. If it
has not been completed, the next block waits for spindle indexing to
be completed. If it is completed, the next block is executed.

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9.SPINDLE SPEED FUNCTION

(S FUNCTION)

- SV speed control mode cancellation

If G96.1 is used to perform spindle indexing, the SV speed control
mode is canceled when spindle indexing is completed.
If G96.2 is used to perform spindle indexing, G96.3 can be used to
check to see if spindle indexing is completed and, if completed, cancel
the SV speed control mode. Issuing G96.2 not followed by G96.3
cannot cancel the SV speed control mode even if spindle indexing is
completed.
Start SV speed control mode cancellation at a path to which the axis of
interest belongs.

- Spindle indexing command during spindle rotation

Issuing G96.1 or G96.2 with a position specified during spindle
rotation causes the spindle to stop at the specified position.
Example)

M03 S1000 ; ............. Rotation at S1000

G96.1 P1 R180. ; ...... Stoppage of rotation at the 180deg position

- Spindle indexing speed

Issuing G96.1 or G96.2 causes a move speed to be dedicated to
spindle indexing. Specify the move speed for spindle indexing,
using parameter No. 11012.

Spindle indexing command (absolute coordinate/machine coordinate)

Using bit 0 (SIC) of parameter No. 11005 can select which coordinate
system, absolute or machine, is to be used in spindle indexing.

Example:

If the difference between the machine and absolute coordinates
(machine coordinate – absolute coordinate) is 100.000:

•

Spindle indexing performed by turning the SV speed

control mode signal (Gn521) OFF (1 to 0) or issuing a
spindle indexing G code (with no R specified)
1. If bit 0 (SIC) of parameter No. 11005 = 0:

Spindle indexing is performed with a machine coordinate
of 100.000 and an absolute coordinate of 0.000.

2. If bit 0 (SIC) of parameter No. 11005 = 1:

Spindle indexing is performed with a machine coordinate
of 0.000 and an absolute coordinate of 260.000.

•

G code-based spindle indexing (with R specified)

Assuming that spindle indexing is specified with R100.000:
1. If bit 0 (SIC) of parameter No. 11005 = 0:

Spindle indexing is performed with a machine coordinate
of 200.000 and an absolute coordinate of 100.000.

2. If bit 0 (SIC) of parameter No. 11005 = 1:

Spindle indexing is performed with a machine coordinate
of 100.000 and an absolute coordinate of 0.000.

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