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3RH, 3TX, LZX coupling links
SIRIUS System Manual
6-4
GWA 4NEB 430 0999-02b
6.2.1 Relay coupling modules versus semiconductor coupling modules
Table 6-3: Comparison: Relay coupling modules and semiconductor coupling modules
Models
Advantages
Disadvantages
• Suitable for direct and alter-
nating voltage
• High switching capacity with-
out heat generation
• Virtually no transfer resis-
tance
(suitable as measured value
transfer switch)
• Electrical isolation
• Safe isolation between con-
tact and coil sides
• No leakage current
• High electromagnetic com-
patibility
• High noise immunity
• Insensitive to overloads and
voltage peaks
• Several switching levels
• Lower switching frequency
• Contact erosion, particularly
in the case of inductive loads
• Inductivity of the coil (distur-
bance)
• Mechanical wear (service life)
• Low direct-current switching
capacity
• Bounce time of the relay con-
tact
• Danger of contact microweld-
ing in the case of capacitive
loads
• No contact welding in the
case of capacitive loads
• High switching frequencies
• High direct-current switching
capacity
• Long service life
• Bounce-free switching
• Insensitive to vibrations and
impact
• Defined transfer resistance
and volume resistance
• Safe isolation between drive
circuit and load in acc. with
DIN VDE 0884
• Silent switching operation
• High temperature rise in the
case of high loads
• Leakage current at output
• Sensitive to peaks in the
power system
• Not suitable as measured
value transfer switch because
of a voltage drop at the
switching transistor
Relay coupling modules
22.5
6.2 mm
17.5
12.5
•
Single-
channel
• 1NO/
1W
• Single-
channel
•
Multi-
channel
• With/wit-
hout
M-O-A
switch
• 1W/1NO/
2NO
• Single-
channel
• Multi-
channel
• Without
switch
• 3NO
• Single-
channel
• Multi-
channel
• Without
switch
• 2W
Semiconductor coupling modules
12.5
• Single-
channel
• Single-channel
• With M-O-A
switch
• Without
switch
6.2 mm