Table of Contents
Advertisement
CHAPTER 4: SETPOINTS
Transformer Overload
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
The Transformer overload element may be used as an instantaneous element with no
intentional delay or as a definite time element. Each winding load current is compared
with the pickup setpoint to produce an alarm or trip condition. Alternatively, the overload
detection is available through the Over-temperature alarm input. An external transformer
over temperature detector can be connected to this input.
Setpoints
Path:
Setpoints > Protection > Group 1(6) > Transformer > Overload
..\Transformer\Transformer Overload
Item Name
Function
Pickup
Pickup Delay
Overtemp Input
Block
Output Relay X
Events
Targets
Xfmr O/L
FUNCTION
Range: Disabled, Trip, Alarm, Latched Alarm, Configurable
Default: Disabled
PICKUP
Range: 50 to 300 % in steps of 1 %
Default: 208 %
This setting identifies the level of transformer overload, where the pickup delay starts
timing. For a two winding transformer, the setting is expressed as a percentage of the
transformer base MVA rating, and is normally set at or above the maximum rated MVA
from the transformer nameplate. For a three winding transformer, the setting is
expressed as a percentage of the winding base MVA rating.
PICKUP DELAY
Range: 0 to 60000 seconds in steps of 1 s
Default: 10 seconds
OVERTEMP INPUT
Range: Off, Any FlexLogic Operand
Default: Off
Select any FlexLogic operand that, when asserted, indicates the transformer cooling
system has failed or an over-temperature condition exists on the transformer.
BLOCK
Range: Off, Any FlexLogic operand
Default: Off
OUTPUT RELAYS
Range: Do Not Operate, Operate
Default: Do Not Operate
EVENTS
Range: Enabled, Disabled
Default: Enabled
Value
Unit
Disabled
208
%
10
s
Off
Off
Do Not Operate
Enabled
Latched
PROTECTION
4–149
- Quick Links:
- 845 Order Codes
- Protection
Hide quick links:
Advertisement
Table of Contents
