3. Cabling
3-5
TI 32P01J10-01EN
3.2
Connecting Power
Power is connected either by using a grounding bipolar three-prong plug or by wiring to
terminals.
The safety control unit and safety node unit in the ProSafe-RS have no power switch. So,
it is recommended that a breaker be installed for each piece of equipment in the same
room, for maintenance and safety requirements.
CAUTION
• Lay power cables 1 cm or more away from signal cables.
• Use power and ground cables conforming to the safety standards of each country.
Type and Maximum Length of Power Cables
Formulas are given below for determining the type and the maximum length (m) of branch cables
from an indoor low-voltage main line.
• The standard type of cable used (nominal cross sectional area) is equivalent to JIS C 3312.
• Calculate the maximum power cable length from the following conditions as shown in the
figure.
However, the power cable must meet the conditions described as “AC Power Specification”
in Section 1.3. The conditions in Section 1.3 always take top priority.
Low-voltage
wiring
Power
distribution
board
Power distribution
board
Equivalent voltage drop (referred to 100 V
supply) of 2 V or less in the main line, viewed
from the indoor power distribution board
Voltage drop of 2 V or less
across this section of wiring
Equip-
ment
L (m)
AC wiring (100 V AC, 220 V AC)
High-voltage
wiring
Voltage drop of 1.2 V or lower
across this section of wiring
L (m)
24 V DC±10 %
DC wiring (24 V DC)
Note:
A voltage drop is thought of as the
voltage fluctuation that would result
if the load were turned on and off.
F030201.ai
Equip-
ment
Figure Maximum Cable Length Calculation Conditions
Oct. 25, 2016-00