KEPCO BOP-ME 1KW, Руководство оператора

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2-10
BOP HIPWR 091719
2.5.3.1 EARTH-GROUND CONFIGURATION
When connecting a programming device to the BOP it is critical that only a single earth-ground
point is connected. Figure 2-2 shows proper earth-ground connections for typical configurations,
as well as an illustration of the consequences of multiple earth ground points. IF THE FOLLOW-
ING CAUTION IS NOT OBSERVED, ANY DAMAGE TO THE UNIT IS THE USER’S RESPON-
SIBILITY AND IS NOT COVERED UNDER THE WARRANTY.
CAUTION: Never connect the both the load terminal tied to the BOP COM terminal and
the programming device common to earth-ground. This allows a ground
loop current to flow within the BOP which will compromise accuracy. Cata-
strophic damage to the BOP will result if the connection between BOP COM
and the load terminal connected to earth-ground is lost.
2.5.3.2 GROUNDING NETWORK CONFIGURATION
When the output is floating there is a tendency for large changes in output voltage to affect the
digital programming section, possibly resulting in an erroneous output. Decoupling capacitors
from each of the two output terminals to the chassis via a terminal block link form a grounding
network. The grounding network is designed to reduce high frequency noise and ensure that the
digital programming section is not adversely affected by the dynamic swing of the output. The
power supply is shipped with the grounding network connected: a connection between terminals
TB1-4 (GND NET) and TB1-5 (GND). To disconnect the grounding network from the output,
remove the connection across TB1-4 and TB1-5.
2.5.4 POWER SUPPLY/LOAD INTERFACE
The general function of a voltage- or current-stabilized power supply is to deliver the rated out-
put quantities to the connected load. The load may have any conceivable characteristic: it may
be fixed or variable, it may have predominantly resistive, capacitive or inductive parameters; it
may be located very close to the power supply output terminals or it may be a considerable dis-
tance away. The perfect interface between a power supply and its load would mean that the
specified performance at the output terminals would be transferred without impairment to any
load, regardless of electrical characteristics or proximity to each other.
The stabilized d-c power supply is definitely not an ideal voltage or current source, and practical
interfaces definitely fall short of the ideal. All voltage-stabilized power supplies have a finite
source impedance which increases with frequency, and all current-stabilized power supplies
have a finite shunt impedance which decreases with frequency. The method of interface
between the power supply output and the load must, therefore, take into account not only the
size with regard to minimum voltage drop, but the configuration with regard to minimizing the
impedance introduced by practical interconnection techniques (wire, bus bars, etc.). The series
inductance of the load wire must be as small as possible as compared to the source inductance
of the power supply: although the error sensing connection to the load compensates for the d-c
voltage drop in the power leads, it cannot compensate for the undesirable output effects of the
power lead inductance. These lead impedances (both power and sensing leads) are especially
important if the load: is constantly modulated or step-programmed; has primarily reactive char-
acteristics; or where the dynamic output response of the power supply is critical to load perfor-
mance.