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Wiring
1) Be sure to use electrical conductors with performance ratings equivalent or
superior to those described in the Maintenance Manual.
2) Do not connect to the same power distribution panel that is intende d for devices,
which can cause line noise, such as, welders and high frequency quenching
machines.
3) Arrange for a qualified electrician to connect the power lines.
1-3-1. Grounding
Use a grounding wire with a cross section of more than 14 mm and a resistance to
ground less than 100 ohms.
This wire size should be greater than AWB (American Wire Gauge) No. 5 and SWG
(British Legal Standard Wire Gauge) No.6.
Generally, the milling machine should be ground to a separate grounding rod. If an
independent ground cannot be provided for the machine, prepare the ground
connection as follow:
1) Connect a single conductor to its grounding terminal. This will avoid possible
serious accidents resulting from ground currents, which m ight otherwise flow
thru the milling machine and damage an electrical component or device within
the electric cabinet.
2) Be careful when using concrete reinforcing rods as grounding points. These
reinforcing rods often are used to ground equipment because they usually offer a
resistance to ground of less t han 100 ohms. In doing so, please make the
connections as follow:
A. Do not use the same grounding -reinforcing rod or grounding terminal for
other devices, since this could lead to line noise such as produced by
electric welders and high frequency quenching m achine.
B. Use a grounding terminal with an adequate electrical performance rating and
is durable in usage.
3) A separate grounding wire should be used, one whose length is as short as
possible.
4) Check the resistance to ground by actual measurement. This should measure less
than 100 ohms if the single device is connected to its own grounding rod.
Desirable independent grounding:
Earth resistance: Less than 100 ohms
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