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 Reserved16-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
A
C
D
06133245
40
100
%
%
A
Max
06133355
4
100
%
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
