Schneider Electric 3.0A User Manual

Page of 40
Micrologic™ 2.0A, 3.0A, 5.0A, and 6.0A Electronic Trip Units
 48049-136-05
Section 2—Ammeter
Rev. 01, 07/2012
© 1999–2012 Schneider Electric All Rights Reserved
16-EN
ENGLISH
Section 2—Ammeter
Display
NOTE: The ammeter display will function only if the trip unit is powered. The 
trip unit is powered by the circuit breaker carrying more than 0.20 x In of 
load current, by being connected to a 24 Vdc external power supply, or by 
having the Full-Function Test Kit or Hand-Held Test Kit connected and on. 
Even with external power supplied, current through the circuit breaker must 
exceed 0.20 x In for the ammeter reading to be accurate to within 1.5%.
A. Alphanumeric screen: Displays ammeter 
information
B. Bar graph: Displays currents using an LED 
bar graph 
C. Menu button: Used to navigate between the 
various menus
D. Scroll button: Used to scroll to the next 
screen in the menus
The default display is the current value of the 
phase at the highest load.
If no information is displayed, contact the local 
field office.
Ammeter Measurements
Micrologic A trip units measure the true RMS 
value of currents. They provide continuous 
current measurement from 0.2 to 20 x In with an 
accuracy of 1.5% (including sensors). No 
auxiliary source is needed where I > 0.2 x In. 
The optional external power supply (24 Vdc) 
makes it possible to display currents where 
I < 0.2 x In and to store values of the interrupted 
current.
A digital LCD screen continuously displays the 
most heavily loaded phases (Imax) or displays 
the Ia, Ib, Ic, Ig, and (on 4-pole circuit breakers 
only) In stored current and setting values by 
successively pressing the navigation button.
Figure 14:
Ammeter
Accessing Information
Three different menus can be accessed:
A. Current measurements
B. Stored peak current measurements
C. Switch settings
In addition, the ammeter can be used to address 
the circuit breaker communication module 
(BCM) in circuit breakers which have the 
optional circuit breaker communication module 
installed.
Figure 15:
Menus
B
menu
40
100 %
%
A
C
D
06133245
40
100 %
%
A
Max
06133355
40
100 %
%
A
Ir=
06133353
40
100 %
%
A
06133354
A–Currents
B–Peak Currents
C–Switch Settings
1.125 x Ir
1 x Ir
0.8 x Ir
0.6 x Ir
0.4 x Ir