GE C70 Instruction Manual page 551

CHAPTER 7: COMMANDS AND TARGETS
If the phase unbalance function is disabled or blocked, the auto-setting process is not functional and the 60P NOT
RUNNING message displays in the second line.
Application with automatic supervision of the automatically calculated factors
When the
CUR UNBALACE 1 AUTO SETTINGS
balancing coefficients is fully automatic. Typical applications require setting this function to "Auto" with the bank de-
energized, then subsequently energizing the capacitor bank. If the function is set to "Auto," it expects to read valid input
signals as a result of bank energization within the flash message duration time to calculate and apply factors. Otherwise,
the value is switched backed to "Disabled." When the bank is energized and the five-cycle timer of the 60P function expires,
the balancing coefficients are calculated and automatically applied. After the new balancing factors are applied, the auto-
setting function switches "Auto" to "Disabled" and the 60P element becomes operational. When in "Auto" mode, the
automatic confirmation command executes immediately after the balancing values are available. The C70 does not
display the applied coefficients in "Auto" mode; rather, they can be viewed in the
If the supervisory conditions are not satisfied in the "Auto" mode within time defined by the
setting, the AUTO FAIL message displays and the 60P function starts running with the pre-existing settings for the
balancing factors.
7.1.1.5 Neutral current unbalance
COMMANDS  CAPACITOR BANK AUTO SETTING  NEUTRAL CURRENT UNBALANCE  NEUTRAL CURRENT
UNBALANCE 1(3)
 NEUTRAL CURRENT
 UNBALANCE 1
Use the auto-setting feature when the capacitor bank is online and the 60N function is enabled. For security reasons, apply
less sensitive settings during the auto-setting process. Temporarily switching to an alternate setting group with less
sensitive pickup thresholds is a method of providing the extra security.
The feature can be used with manual acceptance of the auto-calculated coefficients (the
command switched to "Manual"), or with automatic acceptance of the calculated factors (the
command switched to "Auto").
SET
The feature is used as follows.
Application with manual supervision of the automatically calculated factors
When the
NTRL CUR UNBALACE 1 AUTO-SET
and one for angle of the compensating factor) display the values that best balance the function and prompt for permission
to apply the calculated value as a new setting. When confirmed, the auto-selected value is applied to all setting groups.
After user consent to apply the calculated coefficient is received, the "k =?.???? APPLIED" confirmation message displays
for the duration of the flash message time. The timeout period allows field staff to make note of the newly applied
coefficient. However, it is possible to immediately navigate from this screen. The new setting values can be viewed in the
menu at any time.
SETTINGS
After the process finishes, it is recommended to disable the auto-setting feature. If not disabled by the user, the feature is
automatically disabled when user-initiated front panel interface activity ceases and the C70 display is dimmed.
Certain security conditions are checked during the auto-setting process. If these conditions are violated, the SUPV FAIL
message displays in the second line.
If the neutral voltage unbalance function is disabled or blocked, the auto-setting process is not functional and the 60N NOT
RUNNING message displays in the second line.
C70 CAPACITOR BANK PROTECTION AND CONTROL SYSTEM – INSTRUCTION MANUAL
command is switched to "Manual," the process of calculating and applying the
NTRL CUR UNBALACE 1

AUTO-SET: Disabled
NTRL CUR 1 k=0.0000

APPLY MAGNITUDE? No
NTRL CUR 1 k=0°

APPLY ANGLE? No
command is switched to "Manual," the auto-setting screens (one for magnitude
menu.
SETTINGS
DEFAULT MESSAGE TIMEOUT
Range: Disabled, Manual, Auto
Range: Yes, No
Range: Yes, No
NTRL CUR UNBALACE 1 AUTO-SET
NTRL CUR UNBALACE 1 AUTO-
COMMANDS MENU
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