Siemens SCOR Installation, Operation & Maintenance Instructions Manual page 15

3 Operation by Front Panel
IMPORTANT NOTE
If the installation is equipped with a Power Monitor unit,
the remaining registers can be more easily configured
using the Power Monitor unit. Refer to Siemens Power
Monitor™ Display and Monitoring Unit (Manual
SG-401 8-01 ).
Setting the Time Dial
3. 2.8
There are two Time Dial registers, one for the phases, one for
ground (the 3rd and 4th registers, respectively, in the stepping
sequence). (Some relays do not monitor the ground current.
Check the style number.)
The Time Dial registers may contain any integer from 0 to 99.
Each integer designates one of the hundred characteristic
curves available for each overcurrent function as illustrated
in Figures A.1 through A.16.
3.2.9 Setting Tap Calibration
The Tap Cal registers (5th and 6th of the sequence listed in
Table 3) may hold any integer from 0 to 99. Each integer
represents a one-percent increment between adjacent taps.
Refer to the example at the end of this section to calculate
the required integer.
3.2.1 0 Setting Instantaneous Overcurrent Pickup
The "pin1 " and "pin2" registers (7th and 8th ofthe CONFiguration
sequence) hold the phase trip values for the INST 1 and the INST
2 output contacts. These instantaneous overcurrent registers
may contai � any number in the range 0.50 to 20, representing
0.50 to 20 t1mes the phase TAP position.
Ground current instantaneous trip values are similarly entered
(as multiples of the GROUND TAP position) into registers "nin1 "
and "nin 2" (9th and 1 Oth of the configuration sequence) for the
INST 1 and INST 2 contacts.
3.2. 11 Selecting the Time Overcurrent
Characteristic
The time overcurrent curve type registers (1 1 th and 1 2th in the
sequence of T able 3) may contain any of 1 6 codes, b1 through
b8 and c1 through c8, representing the curve types listed in
Table 1. Refer to Figures A.1 through A.1 6 in Appendix A for
graphic representations of these curves.
3.2.12 Selecting the CT Ratios
Registers 1 3 through 1 6 provide a multiplier that allows the
microprocessor to match the relay's response to the turns ratio
of the external CTs. The relative turns ratio of the CTs is
expressed as a fraction whose denominator is 5.
3.2.13 Current Sensing Range
The 1 7th and 1 8th registers in the sequence display the current
sensing range to which the relay is configured (either HI or LO)
in accordance with the style chart. This is a factory setting .
Demand Period
3.2.14
Register 1 9 (Table 3) indicates the number of minutes in a
demand period . This figure is used to calculate the demand
current. For further information. look under "Instrumentation
Display," Page 14.
3.3 The DATA Mode
3.3.1 Defined
The DATA mode is the normal operating state of the relay. When
in this mode, all the read-only registers which are accessible
from the front panel may be viewed by stepping the MODE
switch, or by automatic scrolling (described later).
In DATA mode, the STATUS LED is off.
3.3.2 Entering the DATA Mode
If the STATUS LED is on, the relay is in the CONFiguration mode.
To leave the CONFiguration mode and enter the DATA mode,
depress the MODE/NEXT switch repeatedly until "ConF" is
displayed on the front panel display. Then hold the switch up for
approximately five seconds until the word "dAtA" appears. At
this time the STATUS LED will extinguish. (Releasing the MODE
switch before five seconds has expired will return the display to
the CONFiguration mode.)
3.3.3 Scrolling
When th � display is left at "dAtA" for 60 seconds, the display will
automatically step through all of the read-only registers (will
"scroll") in the sequence of Table 5, then wrap around and
repeat. This scrolling process first presents the name of the next
register of the sequence (for 0.4 seconds}, then presents the
data of that register (for 0.4 seconds). This process will repeat
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