Configuration - Siemens SIRIUS 3RT Series System Manual

The following surge suppressors are available for the 3RT2/3RH21 contactors:
Table 2- 28
Surge suppressor
Suppression diode
Diode combination:
Suppression and
Zener diode
Varistor
RC element
2.7.3.2

Configuration

Selection aid
The table below compares the effects of the different surge suppressors and specifies the
applications to which they are most suited.
Table 2- 29 Mode of operation and preferred applications of surge suppressors
Surge suppressor Suitable for
Control
voltage
Noise DC
suppress
ion/freew
heel
diode
Diode DC
combi-
nation:
Noise
suppress
ion and
Zener
diode
SIRIUS Innovations
System Manual, 01/2011, A8E56203870002-03
Overview - Surge suppressors
With LED
Size S00
3RT2916-1L
---
3RT2916-1J
---
Overvoltage Effect
is limited ...
OFF-delay
To 0.7 V 
becomes
considerably
longer (6 to 10
times)
With contactors

of size S0 or
larger, "2-stage
drop-out"
cannot be
excluded
OFF-delay
To Zener 
becomes
voltage
longer (2 to 6
times)
A 2-stage drop-

out no longer
occurs
SIRIUS 3RT2 contactors/contactor assemblies
Without LED
Size S0 Size S00
--- 3RT2916-1DG00
3RT2926-1M 3RT2916-1E
3RT2926-1J 3RT2916-1B
--- 3RT2916-1C
Advantages/disadvantages
Simple
Advantag 
implementation
es
Reliable

Non-critical

dimensioning
Low induction

voltage
1)
Disadvan Long drop-out delay

tages
Only suitable for

size S00
Non-critical
Advantag 
dimensioning
es
Attenuation only
Disadvan 
above U
tages
2.7 Accessories
Size S0
---
3RT2926-1E
3RT2926-1B
3RT2926-1C
Preferred
application
Instable control
commands/con
trol supply
voltage
EMC-critical
components in
the vicinity
(10 V)
ZD
171