SIEMENS
7/80
Siemens IC 10 · 2017
Overload Relays
SIRIUS 3RU2 Thermal Overload Relays
3RU2 for standard applications
7
■
Benefits
The most important features and benefits of the 3RU21 thermal
overload relays are listed in the overview table
(see "General
Data", page 7/71 onwards)
.
■
Application
Industries
The 3RU21 thermal overload relays are suitable for customers
from all industries who want to guarantee optimum inverse-time
delayed protection of their electrical loads (e.g. motors) under
normal starting conditions (CLASS 10, 10A).
Application
The 3RU21 thermal overload relays have been designed for the
protection of three-phase and single-phase AC and DC motors.
If single-phase AC or DC loads are to be protected by the 3RU21
thermal overload relays, all three bimetal strips must be heated.
For this purpose, all main current paths of the relay must be
connected in series.
Ambient conditions
3RU21 thermal overload relays compensate temperature in the
temperature range from –40 °C to +60 °C according to
IEC 60947-4-1. At temperatures from +60 °C to +70 °C, the
upper set value of the setting range has to be reduced by a
specific factor in accordance with the table below.
Use of SIRIUS protection devices in conjunction with
IE3/IE4 motors
Note:
For the use of 3RU21 thermal overload relays in conjunction with
highly energy-efficient IE3/IE4 motors, please observe the
information on dimensioning and configuring.
see Application Manual
.
For more information,
see Preface on page 7.
■
Technical specifications
The following technical information is intended to provide an
initial overview of the various types of device and functions.
More information
System Manual "SIRIUS – System Overview",
see
Configuration Manual "Configuring SIRIUS Innovations – Selection Data for
Fuseless and Fused Load Feeders",
see
Manual "SIRIUS – SIRIUS 3RU Thermal Overload Relays /
SIRIUS 3RB Electronic Overload Relays",
see
Technical specifications,
see
Type
3RU2116
3RU2126
3RU2136
3RU2146
Size
S00
S0
S2
S3
Dimensions (W x H x D)
(overload relay with stand-alone installation
support)
• Screw terminals
• Spring-type terminals
mm
mm
45 x 89 x 80
45 x 102 x 79
45 x 97 x 95
45 x 114 x 95
55 x 105 x 117
55 x 105 x 117
70 x 106 x 124
70 x 106 x 124
General data
Tripping in the event of
Overload and phase failure
Trip class
acc. to IEC 60947-4-1
Class
10
10, 10A
Phase failure sensitivity
Yes
Overload warning
No
Reset and recovery
• Reset options after tripping
Manual, Automatic and Remote RESET
(Remote RESET in conjunction with the appropriate accessory)
• Recovery time
-
For automatic RESET
min.
Depends on the strength of the tripping current and characteristic
-
For manual RESET
min.
Depends on the strength of the tripping current and characteristic
-
For remote RESET
min.
Depends on the strength of the tripping current and characteristic
Features
• Display of operating state on device
Yes, by means of TEST function/switch position indicator slide
• TEST function
Yes
• RESET button
Yes
• STOP button
Yes
Protection of motors in hazardous environments
• according to European Directive 2014/34/EU (ATEX)
• according to international standard IECEx
DMT 98 ATEX G 001
II (2) GD
IECEx BVS 15.0046
W
H
D
© Siemens AG 2016