Electro Industries/GaugeTech Nexus 1250, Installation & Operation Manual

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e
Electro Industries/GaugeTech
Doc #: E107-6-07-121
7-7
7.5: Calculating Transformer Loss Compensation Percentages (Work Sheet) 7.5: Calculating Transformer Loss Compensation Percentages (Work Sheet)
Company: ________________________________________________
Date: _________________
Transformer Serial Number_______________________________________
Required Data
Transformer Data
Transformer Bank Rating (Self Cooled) = ______________
Test Phase Voltage (Low Side) = ______________
No Load Loss Watts = ______________
Load Loss Watts = ______________
% Exciting current = ______________
% Impedance = ______________
Nexus Monitor Information
Voltage Transformer Ratio (VTR) = ________________
Current Transformer Ratio (CTR) = ________________
Meter Secondary Voltage (always 120V for Nexus TLC) = 120V
Meter Secondary Phase Current (always 5A for Nexus TLC) = 5A
Losses Due to Iron Losses Due to Iron
No Load KVA Losses = (Exciting Current) x (Bank KVA Rating)
= ________________ x _______________
No Load Loss Vars = SQRT((No Load VA Losses)
2
- ((No Load Watt Losses)
2
)
= SQRT((_________________)
2
- ((___________________)
2
)
Adjust No Load Losses to the Nexus Meter Secondary Voltage:
Watt Losses (FE) = ((120 x VTR)/Test Phase Voltage)
2
x No Load Loss Watts
= ((120 x ______)/__________________)
2
x ________________
Var Losses (FE) = ((120 x VTR)/Test Phase Voltage)
4
x No Load Loss Vars
= ((120 x ______)/__________________)
4
x ________________
Courtesy of NationalSwitchgear.com