2. Abbreviations
CB – Circuit breaker
CBFP – Circuit breaker failure protection
CT – Current transformer
CPU – Central processing unit
EMC – Electromagnetic compatibility
HMI – Human machine interface
HW – Hardware
IED – Intelligent electronic device
IO – Input output
LED – Light emitting diode
LV – Low voltage
MV – Medium voltage
NC – Normally closed
NO – Normally open
RMS – Root mean square
SF – System failure
TMS – Time multiplier setting
TRMS – True root mean square
VAC – Voltage alternating current
VDC – Voltage direct current
SW – Software
uP - Microprocessor
AQ-T257
Instruction manual
Version: 2.00
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© Arcteq Relays Ltd