Omron NSH5 - 10-2010 Operation Manual page 49

Power Supply and FG Wiring
2-2-2 FG Wiring
1,2,3...
Note
(2) Use a DC power supply with little voltage fluctuation.
(3) Do not perform a dielectric strength test.
(4) To comply with the Low-voltage Directive in the EC Directives, use a pow-
er supply with reinforced insulation. Reinforced insulation is a single insu-
lation method that can protect against electrical shock to the same
degree as double insulation.
Recommended model: S82K-03024 (manufactured by OMRON)
(5) Insert a 3-A fuse immediately after the secondary output from the power
supply.
(6) To comply with UL-recognized standards, always use a Class 2 power supply.
Class 2 power supply refers to one in which the current and voltage levels
of the product's secondary output are both limited (100 VA max.), and
which has undergone and passed the necessary tests for UL certification.
The cable connected to the PT has a functional ground terminal (FG)
Wire them according to the conditions described below.
1. If there is a ground potential difference between the NSH5 and the host,
install them as shown in the following diagram.
Do not ground the PT if there is a distance between the PT and the ground
and one-point grounding is difficult.
2. If the PT is installed in the same panel as a source of noise, such as a mo-
tor or an inverter, do not ground the PT.
NSH5
One-point grounding
Be sure to ground correctly to prevent malfunctioning due to noise.
Host
Section 2-2
A
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