1. The new line of circuit breaker IZM
Electronic overcurrent releases

2. The new line of circuit breaker IZM
Electronic overcurrent releases
First I want to present an overview of the electronic overcurrent releases (short form: trip units) with more details.
Because this is the most important device of the IZM circuit breaker.

3. The new line of circuit breaker IZM
Electronic overcurrent releases
Overview of the electronic overcurrent releases
Which features are the same for all types?
Additional features for type V, U, R and D
Special features for type U, R and D
Graphical display
How to do the settings?
Characteristics

4. Trip units: Types of electronic overcurrent releases - overview -
The new line of circuit breaker IZM
Trip units: Types of electronic overcurrent releases
- overview -
XZMA
XZMV
XZMV+XT
XZMU (+XT)
XZMR (+XT)
XZMD (+XT)
XZMA
XZMV
XZMV
XZMU
XZMR
XZMD
L-I
L-S-I
L-S-I-N-G
L-S-I (-N-G)
L-S-I (-N-G)
L-S-I (-N-G)
Earth fault protection ‚XT‘ is optional and for type ‚U‘, ‚R‘ and ‚D‘ even modular for retrofitting.

5. The new line of circuit breaker IZM
Trip units: Types of electronic overcurrent releases
XZMA Release for power distribution system protection
XZMV Release for selective (discriminative) protection
XZMU Release for universal protection
XZMR Digital release, for external parameterization only
XZMD Digital release
Circuit breaker with trip units type ‘U’, ‘R’ and ‘D’ are already equipped with the internal system bus

6. The new line of circuit breaker IZM
Trip units: The different protective ranges
IZM trip units:
L Inverse time-delay overLoad range A, V, V+XT, U, R, D
S Short-time delay short-circuit tripping V, V+XT, U, R, D
I Instantaneous short-circuit tripping A, V, V+XT, U, R, D
N Neutral conductor overload tripping V+XT, U, R, D
G Earth fault tripping (Ground fault) V+XT, U+XT(A), R+XT(A), D+XT(A)
+XT = earth-fault release additional equipment

7. The new line of circuit breaker IZM
Trip units: Same features for all types
XZMA
Mechanical reset:
• indicates a tripping because of overload,
short circuit or earth fault
• press tripped indicator until it latches for reset
of the mechanical reclosing lockout and XHIA
• optional: automatic reset XFR
• optional: safety lock for the tripped indicator
prohibits accidental resetting of the
mechanical reclosing lockout
NEW
NEW

8. The new line of circuit breaker IZM
Trip units: Same features for all types
NEW
XZMA
LED indicators
ACTIVE-LED (flashing green light): overcurrent release is activated = enough supply from the internal current transformers or from an external source (possible for type U, R, D)
ALARM-LED (continuously yellow light): overload alarm, is displayed if the load is higher
than the current setting Ir

9. The new line of circuit breaker IZM
Trip units: Same features for all types
XZMA
NEW
Rating Plug
In = 3200 A
ERROR
Error will be displayed with:
• Microprozessor error
• Internal system bus error
• Memory test error
• Temperature sensor
• Setting error
• Rating Plug is missing or defective

10. The new line of circuit breaker IZM
Trip units: Same features for all types
XZMA
Sealing eyelet
for the optional sealing cover XHB(G)

11. The new line of circuit breaker IZM
Trip units: Same features for all types
XZMA
Test socket
for connection to the test device
also used for connection to XEM-PG(E) with types U, R, D
LED for operating voltage indication
Control buttons
6 LEDs to show test result

12. The new line of circuit breaker IZM
Trip units: Additional features for type V, U, R and D
Rating Plug
In = 3200 A
T. U.
ERROR
XZMV
NEW
Rating Plug:
• plug in version / changeable
• responsible for rated current In of IZM
• range of rated current: 250A-6300A
Take into account:
All adjustments are based on the rated current In!

13. The new line of circuit breaker IZM
Trip units: Additional features for type V, U, R and D
standard now
XZMV
Differentiated trip indication
Indication of the trip reason:
- overload (phases or N-conductor)
- short circuit (delayed trip)
- short circuit (instantaneous trip)
- ground fault
Indicator is illuminated, if protocol-button is pressed

14. The new line of circuit breaker IZM
Trip units: Additional features for type V, U, R and D
XZMV
Selective protection
Delayed short circuit release
Isd = x In (up to 0.8 x Icw for type R, D)
tsd = 0; 20 (M); ms for type V
with OFF-setting for type U, R, D
with tsd up to 4000 ms for type R, D (at reduced Isd)
M: special adjustment for motor protection
with single phase sensitivity
NEW

15. The new line of circuit breaker IZM
Trip units: Additional features for type V, U, R and D
TEST PROTOCOL CLEAR
XZMV
standard now
Test buttons
Test: Internal self test with or without
tripping
Protocol: Finding the cause of trip
Clear: - Interrupt the test
- clear memory (cause of trip)

16. The new line of circuit breaker IZM
Trip units: Additional features for type V, U, R and D
XZMV
Earth fault protection
XZMV+XT
modificated trip unit
only available as plus type (not for retrofitting)
A B C D E
The current setting is depending on the frame size of the breaker. As reference you‘ll find a small glew lable on the front panel.

17. The new line of circuit breaker IZM
Trip units: Special features for type U, R and D
Modular earth fault protection
modular and suitable for retrofitting
available as a single- and plus-type
two different modifications:
only alarm function
with alarm and trip function
XZMU
XZMR
XZMD

18. The new line of circuit breaker IZM
Trip units: Special features for type U
Optional 4-line display for universal trip unit:
LCD-display, very good readable because mounted with an angle of 15°, can be turned in vertical direction by 180°.
Installed with downward inclination
Installed with upward inclination
NEW

19. The new line of circuit breaker IZM
Trip units: Special features for type U, R, D
Standard DIP switches
1. Thermal memory
- can be switched on/off
2. Neutral protection:
- adjustable to 50% or 100% protection
3. Changing from I²t to I4t
- adjustment of the characteristic
in the overload range
(for improved selectivity
to fuses in the middle voltage)
XZMU
NEW

20. The new line of circuit breaker IZM
Trip units: Special features for type U, R, D
XZMU
Modification of the characteristic
Overload range:
Standard: I²t = const.
modification: I4t = const.
for improved selectivity to (middle voltage) fuses
Short time delayed short circuit range:
standard: Isd = const.
modification: I²tsd = const.
(by using „I²tsd“-setting instead of „tsd“-setting)
for improved selectivity to
downstream fuses
NEW

21. The new line of circuit breaker IZM
Trip units: Special features for type U, R, D
XZMU
Instantaneous short circuit release
Adjustment: Ii = In
Ii = MAX
Attention: MAX = 0,8 x Icw
Ii = OFF
Attention: OFF: Ics = Icw ! !
Ics = rated service short-circuit breaking capacity
Icw = rated short-time withstand current

22. The new line of circuit breaker IZM
Trip units: Special features for type U, R, D
XZMU
Instantaneous short circuit release
Calculating MAX and OFF
Example: IZMH2-U1600
- Ics= 100 kA /440VAC
- Icw= 85 kA/ 0,5s
=> MAX = 0.8 x Icw= 68 kA
=> OFF = Ics= Icw= 85 kA/440VAC

23. The new line of circuit breaker IZM
Trip units: Special features for digital types R and D
XZMR
higher settings possible: e.g tsd up to 4 s - Isd up to 0.8 x Icw % protection for neutral conductor
adjustment of settings in smaller steps possible
grahic display for type D (standard)

24. The new line of circuit breaker IZM
Trip units: Digital overcurrent release XZMD
XZMD
Grafic LCD
enables a text output with 8 lines or
the graphical representation of characteristics.
it is used both to display data and to parameterise the overcurrent release as well as the metering function.
the display is operated through the operation keys

25. The new line of circuit breaker IZM Grafic LCD: Display design
Trip units: Digital overcurrent release XZMD
Grafic LCD: Display design
Menu title
8-line alphanumeric display or graphical representation
Status line

26. The new line of circuit breaker IZM Grafic LCD: Status line
Trip units: Digital overcurrent release XZMD
Grafic LCD: Status line
Access with password only
Maintenance required
Parameter set adjusted for protection functions
(4) Edit feature
(5) Adjusted trigger
(6) Possibilities of action

27. Trip units: Digital overcurrent release XZMD
The new line of circuit breaker IZM
Trip units: Digital overcurrent release XZMD
Grafic LCD: Navigation in the menu structure

28. The new line of circuit breaker IZM
Trip units: Digital overcurrent release XZMD
Grafic LCD is displaying both: numerical values and graphical form
Lowest measured value
Present measured value
Highest measured value
(4) 100% of the measured parameter
(5) Width of display

29. The new line of circuit breaker IZM
Trip units: Digital overcurrent release with exclusive
external configuration XZMR
XZMR
Application: no access on site is allowed because
high security is requested
installation in public areas
No operating on site, no display available.
Parameterization only via parameter assignment module PG(E) or via PROFIBUS communication.
Ordering: Digital type with additional plus type IZM-XZMR
! Always including COM-DP module and Breakter Status Sensor XBSS !

30. The new line of circuit breaker IZM
Trip units: How to do the settings
4 protective ranges:
„L“ Overload protection
„S“ Short-time delay short-circuit prot.
„I“ Instantaneous short-circuit protection
„G“ Earth-fault protection
For each range all functions in one horizontal line:
Current setting
Graph with accentuated range
LED for differentiated trip cause indication
Delay time 1. 2. 3. 4.

31. The new line of circuit breaker IZM
Trip units: Characteristics

32. The new line of circuit breaker IZM
Trip units: Characteristics

33. The new line of circuit breaker IZM
Trip units: Characteristics