Invalid Password Entry; Logic Diagrams - GE B90 Instruction Manual

LOGIC DIAGRAMS

4.2.10 Invalid password entry

By default, when an incorrect Command or Setting password has been entered via the front panel three times within five
minutes, the
LOCAL ACCESS DENIED
access via the front panel for five minutes.
By default, when an incorrect Command or Setting password has been entered via any external communications interface
three times within five minutes, the
settings or command access via the any external communications interface for five minutes. The
FlexLogic operand is set to "Off" after five minutes for a Command password or 30 minutes for a Settings password.
These default settings can be changed in EnerVista under Settings > Product Setup > Security.
4.3 Logic diagrams
Logic diagrams in this instruction manual provide an overview of function and settings. A logic diagram is based on
• Inputs-on the left side, which are setting and operands
• Logical gates, which is Boolean algebra to combine logical lines using AND, OR, NOT, and other gates to get a new
logical state
4
• Logical operators, which are timers, one-shot operations, latches, and so on
• Outputs-on the right side, which are products of the manipulations with inputs, logical gates, and logical operators to
produce new operands and define the output state of the element
True and false values are denoted by 1 and 0 respectively. A function usually is high/on/enabled when 1.
Reading from right to left in the following diagram, the
are triggered when either the settings or reset latch in the middle of the diagram is triggered. When this applies, the
operand is triggered after the delay set by the
BUS 1 OP
operand initiates immediately. The settings or reset latch in the middle of the diagram is triggered as follows.
TRIP BUS 1 PKP
• For the reset, one of three conditions are required to meet the OR requirement shown at the bottom left. That is, the
TRIP BUS 1 LATCHING
from the
TRIP BUS 1 RESET
• For the settings, one of 16 input conditions at the top left must be met for the OR, the
Enabled, and the
Table 4-2: Logic diagram symbols
Symbol Description
= Off Output from FlexLogic operand, so user-defined
= Enabled 1 = Enabled and 0 = Disabled
OR Any function input on the left side satisfies the condition
AND All functions input on the left side are required to satisfy the condition
 Not. Negates/reverses the output, for example 0 becomes 1.
 Connection
S, R Set, Reset
T Timer pickup. Triggered by the settings latch in the diagram.
PKP
T Timer reset. Triggered by the reset latch in the diagram.
RST
4-60
FlexLogic operand is set to "On" and the B90 does not allow settings or command level
REMOTE ACCESS DENIED
setting must be 0=Disabled (which is negated by the NOT function to become 1=Enabled), output
FlexLogic operand must be 1, or output from the
output must output as 0, which is then negated/reversed by NOT to become 1.
TRIP BUS 1 BLOCK
FlexLogic operand is set to
and
TRIP BUS 1 OP TRIP BUS 1 PKP
or
TRIP BUS 1 PICKUP DELAY TRIP BUS 1 RESET DELAY
RESET OP
B90 LOW IMPEDANCE BUS DIFFERENTIAL SYSTEM – INSTRUCTION MANUAL
CHAPTER 4: INTERFACES
On and the B90 does not allow
" "
REMOTE ACCESS DENIED
FlexLogic operands on the right side
setting, while the
FlexLogic operand must be 1.
must be
TRIP BUS 1 FUNCTION
TRIP