BE1-50/51B-General Information
1-1
SECTION 1 • GENERAL INFORMATION
DESCRIPTION
BE1-50/51B Overcurrent Relays are microprocessor based, non-directional phase or ground relays that
monitor the magnitude of a single phase ac current to provide accurate instantaneous and time overcurrent
protection for 50 hertz or 60 hertz power systems. Models are available with fifteen popular time
characteristics and a wide range of pickup settings.
APPLICATION
The wide range of pickup settings and front panel selectable time characteristics permit applications
involving coordination with fuses, reclosers, cold load pickup, motor starting, and fixed time requirements.
Integrating reset functions are available to simulate the disk reset of electromechanical relays. BE1-50/51B
Overcurrent Relays have the following standard features.
Independent time and instantaneous elements.
A secure method to manually trip the breaker at the relay front panel.
Direct reading front panel controls.
Minimum pickup setting for safety during installation.
Time characteristics extend to a pickup multiple of 40.
Rugged draw-out construction with steel case.
Magnetic latching targets retain indication without power.
Built-in accuracy eliminates internal adjustments.
Minimum transient overreach.
Field selectable characteristic curve selection.
Field selectable instantaneous or integrating reset.
Field selectable 50 or 60 hertz operation.
Field selectable fixed instantaneous delay (0.0, 0.1, 0.2, or 0.3 second on 100 series relays and 0.0
or 0.1 second on 200 series relays.).
Individual models are available for 1 ampere and 5 amperes sensing input currents and installed in A1 or
S1 cases. BE1-50/51B Overcurrent Relays may be tested without removing the relay from the case.
Shorting contacts are provided for all current inputs when the connection plug or relay chassis is removed
from the relay case. Figure 1-1 shows the front panel of the BE1-50/51B Overcurrent Relay, in an S1 case.
BE1-50/51B Overcurrent Relays have many advantages over other overcurrent relays. The five primary
advantages are:
Time characteristics are defined by equations and graphs.
Field selectable time characteristics.
Very low burden.
Self powered from the sensed current.
Continuous automatic calibration.
MODEL NUMBERS
Model number variations in the BE1-50/51B Overcurrent Relays are specified by a three digit extension to
the model number. Tables 1-1 and 1-2 provide model number, case style, switch SW8-3 selections, and
sensing current input ranges. Internal switches provide for selecting system operating frequencies of 50
Содержание BE1-50B
Страница 5: ...iv BE1 50 51B Introduction Periodic Test 5 9...
Страница 39: ...BE1 50 51B Installation 4 3 Figure 4 3 Panel Drilling Diagram S1 Case Semi Flush Mount...
Страница 43: ...BE1 50 51B Installation 4 7 Figure 4 8 DC Control Connections And Jumper Configuration Terminals...
Страница 44: ...4 8 BE1 50 51B Installation Figure 4 9 BE1 50 51B Overcurrent Relay Rear View...
Страница 59: ...8 2 BE1 50 51B Relay Differences Figure 8 1 Location of Controls and Indicators 100 Series Relays...