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(4) Use the UL-certified products listed below as direct current power supplies.
a) Limited voltage current circuit in accordance with UL508.
A circuit which power is supplied by secondary coil of an insulated transformer that meets the
following conditions
:
- Maximum voltage (No load)
:
30 Vrms (42.4 V peak) or less
- Maximum current : 8 A or less (including short circuit)
Limited by circuit protector (such as fuse) with the following ratings
Voltage without load (V peak)
Maximum current rating (A)
0 to 20 [V]
5.0
Over 20 [V] up to 30 [V]
100
Peak voltage
b) Circuit (class 2) with maximum 30 Vrms (42.4 V peak) or less, which uses class 2 power supply unit
in accordance with UL1310 or class 2 transformer in accordance with UL1585 as the power supply.
6. 5 Grounding
(1) Make sure the product is grounded to ensure the noise tolerance of the controller.
Otherwise it may cause malfunction, damage, electric shock or fire.
Do not share the earth with devices or equipment that generate a strong electromagnetic noise.
(2) Use dedicated grounding.
Use a D-class grounding. (Ground resistance 100
Ω
or less)
(3) The grounding point should be as close as possible to the controller, and the ground wires as
short as possible.
(4) In the unlikely event that malfunction may be caused by the ground, it may be disconnected.
6. 6 Wiring
(1) Preparation for wiring
Switch the power supply off before wiring or plugging and unplugging of connectors.
Mount a protective cover over the terminals after the wires have been connected.
(2) Do not route the digital I/O signal and power cables together.
Malfunctions stemming from noise may occur if the digital I/O signal and power cables are routed
together.
(3) Confirm proper wiring before switrching the power on.
Incorrect wiring will lead to malfunction or may damage the controller or its peripheral devices.
Confirm that there is no mis-wiring before switching the power on.
(4) Reserve enough space for the routing of the cables
If the cables are forced into unreasonable positions, it may damage the cables and connectors, which
may lead to misconnection or short-circuit and result in malfunction.
Avoid bending the cables in sharp angles close to the connectors or where they enter the product.
Fix the cable as close as possible to the connectors so that mechanical stress cannot be applied to
the connectors.
Warning
Warning