Basler BE1-50/51B-229, Инструкция по эксплуатации

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9252000892 Rev A BE1-50/51B-229 Functional Description 3-1
SECTION 3
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FUNCTIONAL DESCRIPTION
INTRODUCTION
This section describes how the BE1-50/51B-229 Overcurrent Relay functions and explains its operating
features. Relay function blocks are illustrated in the block diagram of Figure 3-1.
Figure 3-1. BE1-50/51-229 Function Block Diagram
RELAY FUNCTIONS AND OPERATING FEATURES
The following paragraphs describe BE1-50/51B-229 relay functions and operating features.
Sensing Input
Single-phase ac current from a user-supplied, system current transformer (CT) is brought into the relay at
terminals 5 and 6. The sensing current is applied to the internal Power CT and Signal CT.
Power Supply
Current from the Power CT is rectified, filtered, and supplied to all internal relay circuitry for operating
power. A precision, 5 Vdc output from the Power Supply serves as a reference for automatic calibration.
Instantaneous Signal
Current from the Signal CT is rectified and applied to the Instantaneous Scaling Resistors controlled by
the Instantaneous Pickup Selector Switches (SW1 and SW2). The analog voltage of the instantaneous
input signal developed across the Instantaneous Scaling Resistors is filtered and applied to the
Multiplexor.
Time Signal
Current from the Signal CT is rectified and applied to the Time Scaling Resistors controlled by the Time
Pickup Selector Switches (SW4 and SW5). The analog voltage of the time input signal is filtered and
applied to the Multiplexor.
Microprocessor
Operating power from the Power Supply is applied to the Microprocessor Supervisor Circuit. When the
Microprocessor is active and executing code, the Active/Pickup LED is green. If the input current
decreases below an acceptable level, the Supervisor Circuit interrupts the Microprocessor, halts further