Basler BE1-51C, Instruction Manual

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BE1-51C Operation By Front Panel
4-6
kiloamperes).
The Demand Current registers show the average demand of each monitored phase over a time period that
is entered into the Demand Period register (register 19, Table 4-1). The displayed average is recalculated
each minute for each phase by adding the Demand Period samplings which have accumulated for a given
phase, then dividing this sum by the Demand Period number to obtain the average demand value. The latter
is then displayed in the Demand Current register for the appropriate phase. (The demand current values
may also be read over the data link.)
All of the instrumentation registers (registers 1 through 7) display their data in real time. Note that under
certain conditions the microprocessor may not be able to handle its high priority real-time tasks and also
supply the instrumentation registers with timely data that is within the specified accuracy (±5%). In such
cases the display will show a row of four dashes. The position of these dashes (high or low) indicate which
way the parameter is out-of-range:
If current is below the 0.1 X TAP level, the row of dashes are along the bottom of the display.
If current is above 1-1/2 X pickup, the row of dashes are along the top of the display.
Error Code Display
The error code display is the last register of the sequence described in Table 4-3. In the event of a
malfunction, the Error Code register can narrow the search for possible causes. When this register is at
0000, there is no error message. If not at 0000, consult the Service Manual for interpretation and procedural
suggestions, or contact a Basler representative.
SETTING THE RELAY (EXAMPLE)
Example Defined
The service environment of this hypothetical example is given as follows:
Parameter For Phase For Neutral
Time overcurrent pickup 4.7 A 1.6 A
Pickup Range High Low
Curve shape V e r y I n v e r s e
Inverse
Time delay setting 5.2 sec. @ 28.5 A To be determined.
Instantaneous overcurrent pickup 16.0 A 6.0 A
The following model and style number describes an appropriate relay for this hypothetical application. (The
second style digit indicates that HIGH range was chosen for phase monitoring, and LOW range for neutral
current monitoring.)
Model: BE1-51C Style: H1E Z5J B1NOF
Calculating the Settings
1. The time overcurrent characteristic must be selected such that it will coordinate with the other relays in
the scheme to meet the protective needs of the application. Assume that a Very Inverse function is
suitable for phase protection, and Inverse for neutral protection. From Table 4-2 we see that these two
characteristics are designated b6 and b5 respectively. The table also provides the figure numbers that
illustrate the desired curve sets.