Switch disconnectors and fuses, Introduction – Siemens AC-21A User Manual
Page 2
Siemens LV 10 · 2004
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Switch Disconnectors and Fuses
Introduction
7
■
Overview
Type
3LD20
3LD21
3LD22
3LD25
3LD27
3LD28
SENTRIC LD main control and EMERGENCY-STOP switches from 16 A to 125 A
Rated uninterrupted current
I
U
at 35 °C ambient temperature
A
16
25
32
63
100
125
Rated operating voltage
U
e
V
690
690
690
690
690
690
AC-3 motor load switch
operational switching of individual motors
at 220 ... 240 V
kW
3.0
4.0
5.5
11.0
18.5
22.0
at 380 ... 440 V
kW
5.5
7.5
9.5
18.5
30.0
37.0
at 660/690 V
kW
5.5
7.5
9.5
15.0
22.0
30.0
AC-23A main control switch,
maintenance switch
Frequent, but not operational switching of
individual motors
at 220 ... 240 V
kW
4.0
5.0
6.0
11.0
18.5
22.0
at 380 ... 440 V
kW
7.5
9.5
11.5
22.0
37.0
45.0
at 660/690 V
kW
7.5
9.5
11.5
18.5
30.0
37.0
Switch versions
Front mounting
• Central
✓
✓
✓
✓
–
–
• Four-hole
✓
✓
✓
✓
✓
✓
Base mounting
• Central
✓
✓
✓
✓
–
–
• Four-hole
✓
✓
✓
✓
✓
✓
Distribution board mounting
✓
✓
✓
✓
✓
✓
Molded-plastic enclosure
• Heavy-gauge threaded joints
✓
✓
✓
✓
✓
✓
• Metric screws
✓
✓
✓
✓
✓
✓
Switch accessories
4th pole (N conductor)
(leading switch-on,
delayed switch-off contact)
✓
✓
✓
✓
✓
✓
N terminal
✓
✓
✓
✓
✓
✓
PE/ground terminal
✓
✓
✓
✓
✓
✓
Auxiliary contacts
1 NO + 1 NC
✓
✓
✓
✓
✓
✓
1 NO
✓
✓
✓
✓
✓
✓
1 NC
✓
✓
✓
✓
✓
✓