• t
amb
= Measured (set) ambient temperature (can be set in
̊
C or
̊
F)
• t
max
= Maximum temperature (can be set in
̊
C or
̊
F) for the protected object
• k
max
= Ambient temperature correction factor for the maximum temperature
• t
min
= Minimum temperature (can be set in
̊
C or
̊
F) for the protected object
• k
min
= Ambient temperature correction factor for the minimum temperature
• t
ref
= Ambient temperature reference (can be set in
̊
C or
̊
F, the temperature in which the
given manufacturer presumptions apply and the temperature correction factor is 1.0)
Figure. 5.4.23 - 113. Ambient temperature coefficient calculation (linear approximation, three points).
This ambient temperature coefficient relates to a nominal reference temperature. The default is +40 °C
(the standard ambient temperature rating for machines) which gives the coefficient value of 1.00 for
the thermal replica. The settable thermal capacity curve uses linear interpolation for ambient
temperature correction with a maximum of ten (10) pairs of temperature–correction factor pairs. The
temperature and coefficient pairs are set to the TM> function's settable correction curve.
A
AQ
Q-M257
-M257
Instruction manual
Version: 2.07
226
© Arcteq Relays Ltd
IM00021
Summary of Contents for AQ-M257
Page 1: ...AQ M257 Motor protection IED Instruction manual...
Page 2: ......
