
Siemens AG Low-Voltage Controls and Distribution Data Sheet
SIRIUS SC Function Module 3RF2920-0FA08 Basic Load Monitoring
Main Characteristics:
Applicable on 3RF21 and 3RF23.
No additional space requirements.
Partial load monitoring for up to 6 loads.
Network and thyristor monitoring.
Plug-in control terminal.
Degree of protection IP 20
General Data:
Standards / Approv als DIN EN 60947-4-3
UL 508 / CSA
CE
CCC
Ambient temperature
during operation °C -25 ... 60
during storage °C -55 ... 80
Installation altitude m 0 ... 1000; derating starting at 1000
Impact resistance in acc. with
DIN IEC 68
Vibration performance g 2
Degree of protection IP20
Electromagnetic compatibility (EMC)
Emitted interference
o Conducted interference voltage
IEC 60 947-4-3
o Radiated, radio-frequency
interference voltage IEC 60 947-4-3
Interference resistance
g/ms 15/11
Class A for industrial applications
Class A for industrial applications
o Electrostatic discharge in acc. with
IEC 61 000-4-2 (equivalent to
severity 3)
o Induced HF fields in acc. with
IEC 61 000-4-6
kV Contact discharge 4; air discharge 8; performance criteria 2
MHz 0.15 ... 80; 140 dBµV; performance criteria 1
o Burst in acc. with IEC 61 000-4-4 kV 2/5.0 kHz; performance criteria 1
o Surge in acc. with IEC 61 000-4-5 kV Phase-to-ground 2; phase -to-phase 1; performance criteria 2
Type Screw connection
Connection, auxil. / control contacts
mm²
Conductor cross-section
Stripping length mm 7
Terminal screw M 3
o Tightening torque
Current transformer hole diameter mm 7
0.5 ... 2.5
AWG
20 ... 12
Nm 0.5 ... 0.6
lb.in 4.5 ... 5.3
Main Circuit:
Type 3RF2920-0F A08
Current detection
Rated operating current Ie A 20
• Measuring range
Number of partial loads 6
A 4 ... 22
Subject to changes 08/2003 Page 1/3
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Siemens AG Low-Voltage Controls and Distribution Data Sheet
SIRIUS SC Function Module 3RF2920-0FA08 Basic Load Monitoring
Functional Diagram
Control Circuit:
Type 3RF2900-0FA 08
Operating type DC operation
Rated control supply vo ltage Us V 24
Rated operating voltage max. V 30
Rated operating current mA 15
Threshold voltage V 15
• At threshold current
Drop-out voltage V 5
mA 2
Dimension Drawing:
Equipment Circuit Diagram:
1)
3RF2920-0FA08
Us = 24 V DC
I<
2)
A1 +
A2 IN
OUT
Subject to changes 08/2003 Page 2/3
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Siemens AG Low-Voltage Controls and Distribution Data Sheet
SIRIUS SC Function Module 3RF2920-0FA08 Basic Load Monitoring
Sam ple Circuit Diagram:
A1 Control (PLC)
F1 Main circuit miniature circuit-
breaker
K1 3RF23 solid -state contactor with
plug-on load monitoring module
R1-6 Load resistances
2
L
N
PE
1
1/N/PE 50 Hz 230 V
F1
K1
1 L
PE
3)
R1 R2 R3 R4 R5 R6
A1 +
A2 -
2 T
DC 24 V
L +
L -
A1
L +
L -
1)
I<
A1 +
A2 IN
OUT
2)
D out
D in
1
Internal connection to the solid-state relay / contactor.
2
Bar-type current transformer
Subject to changes 08/2003 Page 3/3
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