514 / 582
BETA Monitoring
Monitoring of Plants and Devices
5
TT3 171 line circuit relays
14/18
Siemens ET B1 · 10/2008
*
You can order this quantity or a multiple thereof.
14
■
Overview
Line circuit relays are used to interrupt circuits and prevent
electromagnetic fields in circuits where there are currently no
active loads.
If the loads are disconnected, and the line circuit relay measures
a usage of only 2 to 20 VA – adjustable – it disconnects the cable
to the supply voltage and switches over to extra-low voltage. As
soon as loads are reconnected, the line circuit relay detects the
increase in usage and switches back to the supply voltage.
While the line circuit relay switches off any unnecessary system
components, it is not a device for ensuring isolation in the sense
of safe disconnection.
The line circuit relay is unable to detect consumers with
electronic power supply units, e.g. electronically controlled
vacuum cleaners. It is expedient to connect such equipment to
a base load resistor (PTC resistor) so that the line circuit relay is
reset to supply voltage.
■
Benefits
•
High availability to a wide range of loads, as all resistive,
capacitive and inductive loads are detected
•
Adjustable from 2 to 20 VA
•
With status display for contact adjustment
•
With switch continuously ON
•
With safety information on stickers for socket outlets and
distribution boards.
■
Technical specifications
■
Selection and ordering data
5
TT3 171
Standards
IEC 60255; DIN VDE 0435-110
Rated control voltage U
c
V AC 230
Operating range
× U
c
0.85 ... 1.15
Rated frequency
Hz
50/60
Rated power dissipation P
v
Electronics
VA
5
Contacts
VA
2.6
Monitoring voltage
V
3
Response value
Adjustable
VA
2 ... 20
Release value
%
of the response value
70
Rated impulse withstand voltage U
imp
Input/output
kV
> 4
Rated operational voltage U
e
V AC 250
Rated operational current
I
e
AC-1
A
16
AC-11
A
3
Contacts
contact
Electrical service life
In switching cycles at 3 A
AC-11 5 × 10
5
Terminals
+/- screw (Pozidriv)
PZ 1
Conductor cross-sections
-
Rigid
Max.
mm
2
2
× 2.5
-
Flexible, with end sleeve
Min.
mm
2
1
× 0.5
Permissible ambient temperature
°C
-20 ...
+45
Degree of protection
Acc. to IEC/EN 60529
IP20, with connected conductors
Safety class
Acc. to EN 61140/ VDE 0140-1
II
Humidity class
Acc. to IEC 60068-2-30
F
Contacts U
e
I
e
U
c
MW DT Order No.
Price
per PU
PG PU PS*/
P. unit
Weight
per PU
approx.
V AC A AC V AC
Unit(s) Unit(s) kg
Line circuit relays
For disconnecting the voltage or field circuit of
electrical systems even when loads are disabled.
1
NC 250
16
230
1
A
5
TT3 171
027 1
1
0.072
Base load resistors for electronic devices
With 15-cm connection wires, end sleeves
and shrink sleeving
C
5
TG8 222
027 1
1
0.010
© Siemens AG 2008