KEPCO KLN 100-7.5, Руководство оператора

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KLN 750W 121912
2-7
CAUTION: WHEN WORKING WITH ACTIVE LOADS, THE VOLTAGE OR CURRENT OF
THE ACTIVE LOAD MUST NOT EXCEED THE MAXIMUM VOLTAGE OR CUR-
RENT RATING OF THE KLN 750W. OTHERWISE THE OVERVOLTAGE OR
OVERCURRENT PROTECTION WILL SHUT DOWN THE POWER SUPPLY.
2.5.1 SAFETY GROUNDING
To minimize shock hazard, the product chassis must be connected to an electrical ground. The
product must be connected to the AC power supply mains through a three-conductor power
cable, with the ground wire firmly connected to an electrical ground (safety ground) at the power
outlet.
Local, national and international safety rules dictate the grounding of the metal cover and case
of any instrument connected to the a-c power source, when such grounding is an intrinsic part of
the safety aspect of the instrument. The ground terminal of the source power connector (Figure
2-1) is connected to the chassis and the instructions below suggest wiring methods which com-
ply with these safety requirements. In the event that the specific installation for the power sys-
tem is different from the recommended wiring, it is the customer's responsibility to ensure that
all applicable electric codes for safety grounding requirements are met. As a precaution, always
connect the screw marked
at the rear panel to proper earth ground.
2.5.2 SOURCE POWER CONNECTIONS
Source power is connected to the power supply via three-wire input power using the source
power cable supplied (see Table 1-3). See Table 1-2 for source power specifications. This power
supply operates from single phase a-c mains power (or between two phases of 3-phase a-c
mains power) over the specified voltage and frequency ranges (Table 1-2) without any need for
range selection.
CAUTION: DO NOT USE AC SUPPLY WHICH EXCEEDS THE INPUT VOLTAGE AND FRE-
QUENCY RATING OF THIS INSTRUMENT. THE INPUT VOLTAGE AND FRE-
QUENCY RATING OF THE POWER SUPPLY ARE SHOWN IN TABLE 1-2. FOR
SAFETY REASONS, THE MAINS SUPPLY VOLTAGE FLUCTUATIONS MUST
NOT EXCEED ±10% OF NOMINAL VOLTAGE.
2.5.3 D-C OUTPUT GROUNDING
Connections between the power supply and the load and sensing connections may, despite all
precautions such as shielding, twisting of wire pairs, etc., be influenced by radiated noise, or
“noise pick-up”. To minimize the effects of this radiated noise the user should consider ground-
ing one side of the power supply/load circuit. The success of d-c grounding requires careful
analysis of each specific application, however, this recommendation can only serve as a general
guideline.
One of the most important considerations in establishing a successful grounding scheme is to
avoid GROUND LOOPS. Ground loops are created when two or more points are grounded at
different physical locations along the output circuit. Due to the interconnection impedance
between the separated grounding points, a difference voltage and resultant current flow is
superimposed on the load. The effect of this ground loop can be anything from an undesirable
increase in output noise to disruption of power supply and/or load operation. The only way to
avoid ground loops is to ensure that the entire output/load circuit is fully isolated from ground,
and only then establish a single point along the output/load circuit as the single-wire ground
point.