MSL-200
CNC LATHE
MAINTENANCE MANUAL
NCT Ipari Elektronikai Kft.
5 / 32
10 September 2018
H-1148 Budapest, Fogarasi út 7.
Phone: +36 1 467 6300
www.nct.hu
1.3
Electrical safety
To ensure safe operation of NC machine, note the following.
1.3.1
Wiring
1.
Please use electric conductors having the same, or better, rated power as pre-set.
2.
Please do not connect the power cord of this machine to a power source with excessive
voltage drop.
3.
Please do not connect the power cord of this machine to a power cable of equipment that
produces noise, such as: welding machine and high frequency quenching machine.
4.
Cables connected with machine power source must be installed by a qualified engineer.
1.3.2
Grounding connection
Use impedance grounding wire having a section area more than 14 mm
2
and an impedance of
less than 100 Ω. Meanwhile, the dimension of grounding wire shall be more than AWG NO.5
and SWG NO.6 Normally an NC machine shall be individually connected to an independent
grounding rod. If independent grounding could not be provided for the machine, please con-
nect to ground according to the following conditions:
1.
Connect an individual conductor to other grounding terminals to prevent resulting
grounding current entering NC machine control and causing a serious accident in case of
failure to peripheral devices.
2.
A cement steel rod can provide an impedance of less than 100 Ω to ground, so it is often
used as a grounding device. When a steel rod cement bar is used for grounding purposes,
please connect it according to the following description:
3.
For a welding machine and high frequency quenching machine that can easily cause
noise, please do not use the same grounding cement steel rod or grounding terminal.
4.
Please use terminals that can withstand the rated power of this machine, which can be
grounded simultaneously.
5.
In case separated grounding wires must be used, make sure to shorten their length.
6.
Please execute actual measuring to check grounding impedance; when one independent
device is connected to grounding rod, its impedance should be less than 100 Ω.
7.
Required independent grounding:
For several equipment items with independent connection to grounding terminals,
please make grounding connection as illustrated in Fig. 1, the grounding impedance is
less than 100 Ω.
Joint grounding: For several equipment items with parallel connection to grounding
terminals, please make grounding connection as illustrated in Fig. 2, the grounding im-
pedance is 100 Ω.
Prohibit serial connection of several equipment items to grounding terminals, as shown
in Fig. 3.
