
APPENDIXG. ALARM LIST
B–63084EN/02
740
No. DescriptionFaulty location and remedy
SPM
indica-
tion(*1)
Message
7n49 SPN_n_ : HIGH CONV.
DIF. SPEED
49 Check whether the calculated differ-
ential speed value exceeds the maxi-
mum motor speed.
In differential speed mode, the speed
of the other spindle converted to the
speed of the local spindle has ex-
ceeded the allowable limit (the differ-
ential speed is calculated by multiply-
ing the speed of the other spindle by
the gear ratio).
7n50 SPN_n_ : SPNDL CON-
TROL OVER-
SPEED
50 Check whether the calculated value
exceeds the maximum motor speed.
In spindle synchronization, the speed
command calculation value exceed-
ed the allowable limit (the motor
speed is calculated by multiplying the
specified spindle speed by the gear
ratio).
7n51 SPN_n_ : LOW VOLT DC
LINK
51 1 Check and correct the power sup-
ply voltage.
2 Replace the MC.
Input voltage drop was detected.
(PSM alarm indication: 4) (Momen-
tary power failure or poor MC contact)
7n52 SPN_n_ : ITP SIGNAL
ABNORMAL I
52 1 Replace the SPM control printed
circuit board.
2 Replace the spindle interface
printed circuit board in the CNC.
NC interface abnormality was de-
tected (the ITP signal stopped).
7n53 SPN_n_ : ITP SIGNAL
ABNORMAL II
53 1 Replace the SPM control printed
circuit board.
2 Replace the spindle interface
printed circuit board in the CNC.
NC interface abnormality was de-
tected (the ITP signal stopped).
7n56 SPN_n_ : INNER COOL-
ING FAN STOP
56 Replace the SPM unit. The cooling fan in the SPM control
circuit stopped.
7n57 SPN_n_ : EX DECEL-
ERATION
POWER
57 1 Decrease the acceleration/decel-
eration duty.
2 Check the cooling condition (pe-
ripheral temperature).
3 If the cooling fan stops, replace the
resistor.
4 If the resistance is abnormal, re-
place the resistor.
An overload was detected in the re-
generative resistance. (PSMR alarm
indication: 8)
Thermostat operation or short–time
overload was detected.
The regenerative resistor was dis-
connected, or an abnormal resis-
tance was detected.
7n58 SPN_n_ : OVERLOAD IN
PSM
58 1 Check the PSM cooling status.
2 Replace the PSM unit.
The temperature of the radiator of the
PSM has increased abnormally.
(PSM alarm indication: 3)
7n59 SPN_n_ : COOLING FAN
STOP IN PSM
59 Replace the SPM unit. The cooling fan in the PSM stopped.
(PSM alarm indication: 2)