Mitsubishi Electric MELPRO MOC-A3T-R, Инструкция по эксплуатации

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13 JEP0-IL9553
Structure
Fig. 1-2 Structure of MOC-A3 series (front view)
Operating Description
1. Protection function
① The power supply can be derived from CT secondary.
② Operating time characteristics of time-lag element
is expressed in the following formula.
･ Extremely inverse (EI):
T =
80
𝐼
2
−1
×
𝐷
10
(s)
･ Very inverse (VI):
T =
13.5
𝐼−1
×
𝐷
10
(s)
･ Normal inverse (NI):
T =
0.14
𝐼
0.02
−1
×
𝐷
10
(s)
･ Definite time (DT):
T = 2 ×
𝐷
10
(s)
③ For switching step number of instantaneous element
(2steps or 3steps) and 3rd step sensitivity (20%,
40%, 60%, or 80% of operation value), use setting
switches (SW2 ～ 4). Note that the sensitivity
setting of 20% is not allowed if the operation
value of instantaneous element is set to 10A. If
you do that, the relay operates as 2-step
characteristic.
④ The relay calculates and compares input current
of each phase with the setting value. When the
relay operates, the operation indicator turns
according to the fault phenomena. If you reset
operation indicator, move reset lever up and down.
(
●
： Operation indication)
Fault phenomena Display of operation indicator
Type Phase R-phase T-phase Inst.
Overload
R-S ● ○ ○
S-T ○ ● ○
T-R ● ● ○
R-S-T ● ● ○
Short
circuit
R-S ● ○ ●
S-T ○ ● ●
T-R ● ● ●
R-S-T ● ● ●
⑤ As for the output contact of the relay, once it
operated, it will reset in approx. 60ms after
holding when input current is less than the
setting value.
Setting switches for using
condition
Don't use any tool with a sharp point
when the switches are set.
(It may cause damage to the switch
lever.)
SW1
Freque
ncy
SW2
Inst.
Step No.
ON 50Hz ON 3steps
OFF 60Hz OFF 2steps
SW3 SW4
Inst.
Sensitivity
OFF OFF 20%
OFF ON 40%
ON OFF 60%
ON ON 80%
SW5 SW6 Time curve
OFF OFF EI
OFF ON VI
ON OFF NI
ON ON DT
Factory settings are set to a default
of OFF.
Setting switches for
operation value and dial
Set the setting values. The
black part is equal to maximum
value, but the numerical
display is turned off.
Don't leave the switches with
halfway state.
RUN indicated LED (Green)
It shows the result of self-
monitoring. It lights up in
normal condition.
Operation indicator reset lever
Move this lever up and down, then the operation
indicator resets.
(Note) Don't pull the lever strongly.
Numerical display LED
Following item is displayed
by indicator select switch
setting.
・ Current measurement
・ Time lapse
・ Setting value
・ Fault record
・ Clear fault record
Indicator select switch
The numerical display shows
according to this selection
switch. Don't leave this
switch with halfway state.
Operation indicator
The indicator turns from black into orange color
when the protection element is put into operation.
CPU reset button
While this button is pressed, the
relay function is locked and the
RUN indicated LED is turned off.