Table of Contents
Advertisement
CHAPTER 6: SETPOINTS
339 MOTOR PROTECTION SYSTEM – INSTRUCTION MANUAL
will flash upon Phase Undervoltage operation, and will automatically reset when the
activating condition clears. If Latched Alarm is selected, the "ALARM" LED will flash upon
Phase Undervoltage operation, and will stay "ON" after the condition clears, until a reset
command is initiated. The TRIP output relay will not operate if the Latched Alarm or
Alarm function is selected. Any assignable output relays can be selected to operate
when the setting PH UV FUNCTION is selected as Latched Alarm, Alarm, or Trip.
PH UV PKP
Range: 0.00 to 1.25 x VT in steps of 0.01
Default: 0.75 x VT
This setting defines the phase UV pickup level, and it is usually set to a level, below which
the drawn current may cause dangerous motor overheating conditions.
PH UV CURVE
Range: Definite Time, Inverse Time
Default: Inverse Time
This setting selects the type of timing-inverse time/definite time to define the time of
undervoltage operation based on the selected UV time delay, and the actual
undervoltage condition with respect to the selected UV pickup.
PH UV DELAY
Range: 0.1 to 600.0 sec in steps of 0.1 sec
Default: 2.0 s
This setting specifies the time delay used by the selected "PHASE UV CURVE" type of
timing, to calculate the time before UV operation.
PH UV PHASES
Range: Any One, Any Two, All Three
Default: Any One
This setting selects the combination of undervoltage conditions with respect to the
number of phase voltages under the undervoltage pickup setting. Selection of "Any Two"
or "All Three" would effectively rule out the case of single VT fuse failure.
PH UV MIN VOLTAGE
Range: 0.00 to 1.25 x VT in steps of 0.01
Default: 0.30 x VT
The minimum operating voltage level is programmable to prevent undesired UV
operation before voltage becomes available.
OUTPUT RELAY 4 to 6 / OUTPUT RELAY 5 to 6
Range: Do not operate, Operate
Default: Do not operate
Any assignable output relay can be selected to operate upon Phase Undervoltage
operation. When the SWITCHING DEVICE is selected as BREAKER, the assignable output
relays will be Output Relay 4 to 6. When the SWITCHING DEVICE is selected as
CONTACTOR, the assignable output relays will be Output Relay 5 to 6.
BLOCK 1/2/3
Range: Off, Contact Input 1 to 10, Virtual Input1 to 32, Remote Input 1 to 32, Logic Element
1 to 16
Default:Off
Three blocking inputs are provided for Phase UV. When any of the selected blocking
inputs is on, the Phase UV function is blocked. The available selections for each block can
be any Contact input, Virtual Input, Remote Input, or Logic Element.
S3 PROTECTION
6–91
Advertisement
Table of Contents
