Schneider Electric and 6.0A User Manual

Page of 40
Micrologic™ 2.0A, 3.0A, 5.0A, and 6.0A Electronic Trip Units
 48049-136-05
Section 1—General Information
Rev. 01, 07/2012
© 1999–2012 Schneider Electric All Rights Reserved
10-EN
ENGLISH
Trip Unit Switches
Long-Time Protection
Long-time protection protects equipment against 
overloads.
Long-time protection is standard on all trip 
units.
The long-time pickup (Ir) (A) sets the 
maximum current level (based on sensor 
plug rating In) which the circuit breaker can 
continuously carry. If current exceeds this 
value, circuit breaker will trip after the preset 
time delay. The long-time pickup (Ir) is 
adjustable from 0.4–1.0 times the sensor 
plug rating (In). 
The long-time delay (tr) (B) sets the length of 
the time that the circuit breaker will carry an 
overcurrent (below the short-time or 
instantaneous pickup current level) before 
tripping. See Table 1 for delay settings.
Both long-time pickup and long-time delay 
are on the field-replaceable adjustable rating 
plug. To change settings to more precisely 
match the application, various rating plugs 
are available. For instructions on replacing 
the rating plug, see Section 5 —Adjustable
Rating Plug Replacement.
For Masterpact™ NT and NW circuit 
breakers, the In value can be changed by 
replacing the sensor plug below the trip unit. 
For further information, see the instructions 
packed with the sensor plug replacement kit.
The overload indicator light (C) indicates that 
the Ir long-time pickup threshold has been 
exceeded.
Long-time protection uses true RMS 
measurement.
Thermal imaging provides continuous 
temperature rise status of the wiring, both before 
and after the device trips. This allows the circuit 
breaker to respond to a series of overload 
conditions which could cause conductor 
overheating, but would go undetected if the 
long-time circuit was cleared every time the load 
dropped below the pickup setting or after every 
tripping event.
NOTE: Micrologic trip units are powered from the circuit to always provide 
fault protection. All other functions (display, metering, communications, etc.) 
require external power. See 15 for more information.
Figure 7:
Long-Time Protection Switches
Table 1:
Micrologic Trip Unit Long-Time Delay Values
Setting
1
Long-Time Delay in Seconds
2
tr at 1.5 x Ir
12.5
25
50
100
200
300
400
500
600
tr at 6 x Ir
0.5
1
2
4
8
12
16
20
24
tr at 7.2 x Ir
0.34
3
0.69
1.38
2.7
5.5
8.3
11
13.8
16.6
1
Ir = In x long-time pickup. In = sensor rating. Trip threshold between 1.05 and 1.20 Ir.
2
Time-delay accuracy +0/-20%
3
For Micrologic 5.0A and 6.0A trip units, when tsd is set to 0.4 on or 4.0 off, then tr = 0.5 instead of 0.34.
NOTE: If checking trip times, wait a minimum of 15 minutes after circuit 
breaker trips before resetting to allow the thermal imaging to reset 
completely to zero or use a full-function test kit to defeat the thermal 
imaging.
Ir
2
2.5
3
4
5
6
8
10
1.5
setting
Isd
instantaneous
long time
alarm
tr
(s)
.4
.5
.6
.7
.8
.9
.95
.98
1
Ir
x In
.5
1
2
4
8
12
16
20
@ 6 Ir
24
06134243
In
2
3
4
5
6
8
10
12
1.5
setting
Ii
instantaneous
long time
alarm
tr
(s)
.4
.5
.6
.7
.8
.9
.95
.98
1
Ir
x In
.5
1
2
4
8
12
16
20
@ 6 Ir
24
06133203
.4
.5
.6
.7
.8
.9
.95
.98
1
delay
short time
I i
tsd
(s)
on   
 
I
2
t
.
2
.
3
.
4
.
4
.
1
.
2
.
3
.
1
0
off
instantaneous
long time
alarm
Ir
x In
.5
1
2
4
8
12
16
20
tr
(s)
@ 6 Ir
24
setting
x Ir
2
2.5
3
4
5
6
8
10
Isd
1.5
x In
3
4
6
8
10
12
15
off
2
06133204
.4
.5
.6
.7
.8
.9
.95
.98
1
delay
short time
I i
tsd
(s)
on   
 
I
2
t
.
2
.
3
.
4
.
4
.
1
.
2
.
3
.
1
0
off
instantaneous
long time
alarm
Ir
x In
ground fault
B
C
D
E
F
G
H
J
Ig
tg
(s)
on   
 
I
2
t
.
2
.
3
.
4
.
4
.
1
.
2
.
3
.
1
0
off
A
.5
1
2
4
8
12
16
20
tr
(s)
@ 6 Ir
24
setting
x Ir
2
2.5
3
4
5
6
8
10
Isd
1.5
x In
3
4
5
8
10
12
15
off
2
test
06133351
A
B
C
Micrologic 2.0A Trip Unit
Micrologic 3.0A Trip Unit
A
B
C
A
B
C
Micrologic 5.0A Trip Unit
Micrologic 6.0A Trip Unit
A
B
C