TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
Objective
The purpose of this document is to provide general guidelines for
periodic maintenance of Servo Motor and Servo Drive
Applicable Machine models
Machines with Servo power Unit
1. Maintenance Guideline for Servo Motor
Safety warning: Ensure that the motor is electrically isolated from
the power supply during the maintenance work. Even if the motor is at
standstill, there could be some voltage at the motor power terminals.
Take sufficient precautions to avoid electric shocks.
Use safety shoes and gloves while handling the motor during
maintenance.
1A: Mounting, termination & cabling:
a) Ensure that the motor is properly mounted on the Flange (Bell
housing) and all the mounting nuts and bolts are properly
tightened so that it remains secured to the mounting structure.
This should be done at least once in six months.
Pic 1
b) Check and ensure proper gap between coupling halves of motor and
pump (Refer Pic 2 & 3 below), check for the proper alignment and
spider position. Improper alignment and any damage on coupling
or Spider can lead to unbalance forces acting on the motor shaft
while running which can cause damage to motor bearings. This
should be done at least once in 3 months.
Rev. No. Prepared Approved Date: T. B. No.:
00 NVK NVK 10.04.2019 07/2019
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
Coupling and gap between
two halves
Spider
Pic 2
Pic 3
c) Do not hammer the shaft or bearing of the motor (Refer Pic 4)
Use suitable devices (Jig/puller/pusher/coupler) to insert or
removing the coupling from the motor shaft.
Pic 4
Coupling Insert Coupling Removal
Rev. No. Prepared Approved Date: T. B. No.:
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
d) Ensure proper connections and tightness of power termination,
cooling Fan and KTY connections inside the motor terminal box.
Any loose connections can result in abnormal heat generation and
temperature rise of the connection points (refer pic 5,6) and
can cause malfunction of motor, winding failure, cable burning
and damage to the motor as well as to the drive.
Use proper tool to check the connections.
Proper Tool (Star Screw Driver)
KTYKTY
connection
Motor Power Terminals
Cooling Fan
connection
Pic 5- Before interface Capacitor for cooling Fan Pic 6 – After Interface
Note: The Picture 5 & 6 represent Toshiba Make motor (Realland)
e) Earthing(PE)
i) Based on the Earthing requirement the electrode
diameter/width and number of pits and depth of
penetration should be designed. Earth resistivity and
soil resistivity must be measured based on the procedure
given in the standard ( Refer standard IS3043:1987)
ii) If number of machines are connected to a single earth
pit, it has to be ascertained that the Earthing system
should have resistance less than 1 Ohm
iii) Check the tightness of Earth connection to the machine
regularly (once in three months).
iv) Check and maintain the voltage between Earth and Neutral
is less than 2V regularly (Once in a week)
Rev. No. Prepared Approved Date: T. B. No.:
00 NVK NVK 10.04.2019 07/2019
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
1B: Cleaning & dust removal:
a) Regularly clean the area around the motor so that it is free from
dust, moisture and any other materials or objects(Once in 2 weeks)
b) Clean the outer surface of the motor with blower or dry cloth to
remove the accumulated dust,(refer pic 7, 8 below). This will
improve the heat transfer when the motor is in operation(Once in a
month)
Pic 7 Pic 8
c) Ensure that the cooling fan blades are clean by blowing air
through the fan grill and free from dust as shown in Pic 9(Once in
a month)
Pic 9
Rev. No. Prepared Approved Date: T. B. No.:
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
1C : Bearing Replacement:
Bearing life depends on motor running hours, load condition and
operating temperature. Considering above factors, the life of the
Motor Bearing is 5 years. So, it is recommended to change the Bearing
voluntarily once in 5 years.
Customer has to contact Toshiba Machine (Chennai) Pvt. LTD for
getting authorized service center details to replace the Bearing.
1D : General precautions:
Some of the precautions are listed below which need to be taken while
normal working or maintenance of the motor:
a. Do not leave motor terminal box open. This will avoid the
possibility of accidently getting electric shock if the human
body touches the exposed terminals.
b. Do not run the motor when motor cooling fan is not running.
c. Do not touch the motor with wet hands/cloth.
d. Do not bring any inflammable objects near the motor as it may
catch fire or explode.
e. Do not step or sit on the motor.
f. Do not remove name plate from the motor or tamper with the serial
number. This will lead to warranty refusal.
g. While storing the motor, ensure that the storage location is free
from dust and moisture.
Rev. No. Prepared Approved Date: T. B. No.:
00 NVK NVK 10.04.2019 07/2019
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
2. Maintenance Guideline for Servo Drive
For long trouble free operation of Servo Drive, preventive maintenance
is always recommended. The servicing cycle depends up on the
environment i.e. if it is dusty and corrosive, frequent cleaning is
required. We recommend below general guidelines for periodic
maintenance
Safety warning: Switch off the mains AC input supply to panel and
drive before starting the maintenance activity. After turning off the
input power, wait for the DC bus capacitors to discharge to a safe
voltage level. This will be indicated by turning off of the red LED on
the drive front facia.
Use safety shoes and gloves while handling the drive during
maintenance.
2A: Mounting, termination & cabling:
a) Ensure that the Drive is properly mounted inside the control
panel and all the mounting nuts and bolts are properly tightened
so that it remains secured to the mounting structure(see pic 10).
This needs to be done at least once in six months.
Drive mounting
Bolts- TOP
Drive mounting
Bolts-BOTTOM
Pic 10
Rev. No. Prepared Approved Date: T. B. No.:
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
b) Reinforce and tighten the drive power terminals once in 3-4
months(see pic 11). Use proper tool for tightening the terminals.
POWER
TERMINALS
Pic 11
Note: Loose power connections can result in excessive heating at the
terminal contact area and can lead to arcing and melting of
connectors. This can further lead to intermittent currents and
electrical noise and can as well cause the damage to the drive
electronic parts/components.
c) Ensure proper tightness of Earth connection and distribution of
Earth connection to drive and other parts, Power contactor and
Choke are properly secured to their mounting bases and proper
tightness of power terminals and not corroded inside the
control/power panel. This will reduce the possibility of
electrical noise generation that can result in unforeseen
problems and failures. Use proper tools for this job which should
be done at least once every six months. Refer Pic 12 below for
reference.
Pic 12
Earth Bar Power contactor Choke at the Drive Input power
(Between Drive & motor)
Rev. No. Prepared Approved Date: T. B. No.:
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
d) Earthing(PE)
i) Based on the Earthing requirement the electrode
diameter/width and number of pits and depth of
penetration should be designed. Earth resistivity and
soil resistivity must be measured based on the procedure
given in the standard ( Refer standard IS3043:1987)
ii) If number of machines are connected to a single earth
pit, it has to be ascertained that the Earthing system
should have resistance less than 1 Ohm
iii) Check the tightness of Earth connection to the machine
regularly (once in three months).
iv) Check and maintain the voltage between Earth and Neutral
is less than 2V regularly (Once in a week)
2B: Cleaning & dust removal:
a) Clean the dust and dirt accumulated on the drive body using low
suction power, clean and dry air vacuum cleaner once in a month
so that the air is sucked from all the grids as well as top &
bottom portions of the heat sink. The air suction points are as
shown in Pic 13 below. The accumulated dust on the drive
internal parts and boards as shown in Pics 14a & 14b below can
affect the heat transfer thereby causing the overheating of the
components that can result in erratic drive operation, damage to
drive components and unpredictable types of failures. The
conductive type of dust when gets accumulated on the live drive
internals parts can provide path for electrical short circuits
which can result in malfunction or drive failure.
Pic 13
Rev. No. Prepared Approved Date: T. B. No.:
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
Poor Maintenance:
Pic 14a Pic 14b
b) Keep the area inside the control panel free from dust, dirt and
moisture. Use low pressure vacuum cleaner as mentioned above for
removal of dust / dirt accumulated on different parts of the
control panel. Maintenance
c) Keep the area around the control panel free from dust, plastic
powder (like PVC), water or any other type of hazardous
material. Entry of water or moisture or hazardous powder inside
the drive can cause corrosion of the drive components (as shown
in Pic 15 below) leading to damage of components and subsequent
drive failure.
Poor Maintenance:
Pic 15
d) Cooling fans are used to provide proper ventilation inside the
panel so that the heat generated inside the drive is effectively
removed from the drive / panel to ensure long and trouble free
drive operation. Therefore the panel cooling system should be
regularly inspected, and more frequently.
Rev. No. Prepared Approved Date: T. B. No.:
00 NVK NVK 10.04.2019 07/2019
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
Ensure that the panel cooling fan blades and fan grills (as
shown in Pic 16c) are cleaned regularly so that they are free
from dust. Dust accumulation on the fan impeller blades can
cause mechanical imbalance leading to fan failure.
Regularly clean the panel air filters and filter covers as the
accumulated dust on the filters & covers (as shown in Pic 16a
and 16b) affect the panel internal air circulation leading to
panel internal temperature rise. This can result in frequent
drive tripping due to over temperature and also the failure of
drive internal electronic components due to thermal stress.
Replace the air filters every 4-6 months.
Filter cover
Pic 16a
Pic 16b Filter
Rev. No. Prepared Approved Date: T. B. No.:
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TECHNICAL BULLETIN
Subject: Maintenance information of Servo motor and
Servo drive
Pic 16c Fan Blade & Fan
grill
2C : General precautions:
Some of the precautions mentioned below which need to be taken care
while normal working or maintenance of Drive.
a) Do not leave drive cover open. This will avoid the possibility
of accidently getting electric shock if the human body touches
the exposed live parts.
b) Do not turn ON the drive when panel cooling fan is not running.
c) Do not touch the drive with wet hands.
d) Do not bring any inflammable objects near the drive / panel as
it may catch fire or explode.
e) Do not remove name plate from the drive or tamper with the
serial number. This will lead to warranty refusal.
f) Do not reset and re-start the drive frequently on the same
fault, it will lead to permanent drive failure.
g) Ensure proper Input supply voltage and power factor. Leading
power factor can damage the drive power components.
h) While storing the drive, ensure that the storage location is
free from dust and moisture.
i) Maintain regular fault log which will be useful for failure
analysis.
Customer has to contact Toshiba Machine (Chennai) Pvt. LTD for
getting authorized service center detail.
Rev. No. Prepared Approved Date: T. B. No.:
00 NVK NVK 10.04.2019 07/2019
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