• Inverse definite minimum time (IDMT): gives the TRIP signal after a time which is in relation
to the set pick-up voltage
U
set
and the measured voltage
U
m
(dependent time
characteristics).
The IDMT function follows this formula:
Where:
•
t = operating time
•
k = time dial setting
•
U
m
= measured voltage
•
U
s
= pick-up setting
•
a = IDMT Multiplier setting
The following table presents the setting parameters for the function's time characteristics.
Table. 5.3.11 - 114. Setting parameters for operating time characteristics.
Name
Range
Step
Default
Description
Delay type 1: DT
2: IDMT
-
1: DT
Selection of the delay type time counter. The selection possibilities are
dependent (IDMT, Inverse Definite Minimum Time) and independent (DT,
Definite Time) characteristics.
Definite
operating
time delay
0.000…800.000s 0.005s 0.040s
Definite time operating delay. The setting is active and visible when DT is
the selected delay type.
When set to 0.000 s, the stage operates as instant stage without added
delay. When the parameter is set to 0.005...1800 s, the stage operates
as independent delayed.
Time dial
setting k
0.01…60.00s
0.01s
0.05s
This setting is active and visible when IDMT is the selected delay type.
Time dial/multiplier setting for IDMT characteristics.
IDMT
Multiplier
0.01…25.00s
0.01s
1.00s
This setting is active and visible when IDMT is the selected delay type.
IDMT time multiplier in the U
m
/U
set
power.
Table. 5.3.11 - 115. Setting parameters for reset time characteristics.
Name
Range
Step
Default
Description
Release
time delay
0.000…150.000s 0.005s 0.06s
Resetting time. The time allowed between pick-ups if the pick-up has not
led to a trip operation. During this time the START signal is held on for
the timers if the delayed pick-up release is active.
Delayed
pick-up
release
1: No
2: Yes
-
1: Yes
Resetting characteristics selection either as time-delayed or as instant
after the pick-up element is released. If activated the START signal is
reset after the set release time delay.
Time calc
reset after
release
time
1: No
2: Yes
-
2: Yes
Operating timer resetting characteristics selection. When active, the
operating time counter is reset after a set release time if the pick-up
element is not activated during this time. When disabled, the operating
time counter is reset directly after the pick-up element is reset.
A
AQ
Q-F215
-F215
Instruction manual
Version: 2.04
183