BE1-51/27R - Tests And Adjustments
5-11
NOTE
Selection of one of the specific overcurrent pickup points provided by the front panel TAP
Selector (and with the front panel TAP CAL control fully CW) will permit a pickup point
within ±5% of the selector value without having to connect the relay to a test setup to
verify the setting. If present, the front panel TAP (NEUTRAL) selector and the front panel
CAL (NEUTRAL) control provide this function for the neutral overcurrent pickup point.
However, if the desired pickup point falls between these front panel TAP selector settings,
or if the instantaneous overcurrent option 1-1 or 1-2 is present, the relay should be
connected to a test setup for a precise setting, then the following steps should be per-
formed.
Step 6.
Slowly increase the input current from 0 until the appropriate phase timing indicator just illuminates.
RESULT:
The overcurrent pickup point should be whichever is greater: 50 ±10% of the front
panel setting or 50 mA (Sensing Input Ranges 1, 2, 3, 4, and 5) or 10 mA (Sensing
Input Ranges 6, 7, 8, and 9).
ADJUSTMENT OF CONTROLS FOR RELAY OPERATION
The following procedures set up the relay for use in a protective scheme. The procedures are arranged in
a logical sequence that prevents upsetting previous control settings. For relays not having certain options,
skip the corresponding adjustment paragraph. These paragraphs are identified by their headings.
TAP and TAP (NEUTRAL) Selector Setting
Step 1.
Connect the test setup to the relay according to the sensing input type present in the relay as fol-
lows:
(a) Sensing Input Type M or N: Refer to Figure 5-1. Because the relay front panel TIMING
indicator provides the needed pickup indication, do not connect the test setup to the output
terminals. The current sense terminals for the desired range (HIGH or LOW), however,
should be connected to the relay.
(b) Sensing Input Types Y or Z: Refer to Figure 5-6. Because the relay front panel TIMING
indicator provides the needed pickup indication, do not connect the test setup to the output
terminals. The front panel TAP selector is ganged and the adjustment of one input phase
automatically aligns the other, thus, only one set of current sense terminals need be
connected. For adjustment of the front panel TAP (NEUTRAL) selector, the relay is re-
connected for neutral sensing by this procedure.
(c) Sensing Input Types B, C, R, or S: Refer to Figures 5-2 or 5-4. Because the relay front
panel TIMING indicator provides the needed pickup indication, do not connect the test
setup to the output terminals. The desired range terminals (HIGH or LOW), however,
should be connected to the relay. The front panel TAP selector is ganged and the
adjustment of one input phase automatically aligns the others, thus, only one set of current
sense terminals need be connected.
(d) Sensing Input Types E and F, or U and W: Refer to Figures 5-5 or 5-3. Because the relay
front panel TIMING indicator provides the needed pickup indication, do not connect the test
setup to the output terminals. The front panel TAP selector is ganged and the adjustment
of one input phase automatically aligns the others, thus, only one set of current sense
terminals need be connected. For adjustment of the front panel TAP (NEUTRAL) selector,
the relay is re-connected for neutral sensing by this procedure.