Double Throw Switches - Siemens TYPE VBII Series Application Manual

Double Throw Switches

Description & Application
Double throw safety switches are
intended to transfer loads from one
power source to another. All two- and
three pole double throw switches are
suitable for use as service equipment.
All are UL listed. Switches are rated for
use on systems up to 10,000A when
protected with Class H fuses or
100,000A when protected with Class R
or Class T fuses¡. They can also be used
to connect a single source of power to
either of two loads. In this application it
is necessary to field modify fusible
switches so that the fuses are on the
Double Throw Switches
Number
System Voltage of Poles
Heavy Duty Fusible (30-200A with Class H fuse provisions)
2
240
Volt AC
3
or
250
ON
OFF
Volt DC
ON
600
Volt AC,
3
250
Volt DC
➁
Heavy Duty Non-Fusible
2
240
Volt AC
or
250
Volt DC
3
ON
OFF
ON
3
600
Volt AC
or
4 ➄
250
Volt DC
➀ Use HS Type hubs for 30–200A switches; 400A and larger switches do not have hub provisions.
28
➁ All Heavy Duty double throw switches with catalog numbers starting with "DT" are rated 200,000 AIC max. when protected by Class R, J or T fuses.
Fuse ampere rating must not exceed switch ampere rating.
➂ Move load base.
➃ Catalog No. F355SSDTK will accept Class T Fuse only
➄ Four pole switches are not approved for service entrance.
load side of the switching mechanism.
A cover interlock is provided on all
ampere ratings. The operating handle
may be padlocked in the OFF position.
Fuse Capabilities of Fusible Switches
Amp
Rating
30 & 60A, 240V Std Yes (kit) No
30 & 60A, 600V Std Yes (kit) No
100 & 200A
400 & 600A DTF No
Type 1– Indoor
Amps Catalog Number
➁
200 DTF224
30 DTF321
60 DTF322
100 DTF323
200 DTF324
400 DTF325
600 DTF326
30 DTF361
60 DTF362
100 DTF363
200 DTF364
400 DTF365
30 DTNF221
60 DTNF222
100 DTNF223
200 DTNF224
400 DTNF225
30 DTNF321
60 DTNF322
100 DTNF323
200 DTNF324
400 DTNF325
600 DTNF326
800 DTNF327
30 DTNF361
60 DTNF362
100 DTNF363
200 DTNF364
400 DTNF365
600 DTNF366
800 DTNF367
1200 DTNF368
30 —
60 —
100 —
200 NF454DTK
400 NF455DTK
600 NF456DTK
800 NF457DTK
Fuse Type
H R T J
No
➂
Yes
➂
Std Yes (kit) Yes (kit) Yes
➂ ➃
No Yes Std
Type 3R – Outdoor➀ Type 12/3R Industrial
Catalog Number Catalog Number
DTF224R
DTF321R
DTF322R
DTF323R
DTF324R
—
—
—
—
DTF363R
DTF364R
—
—
—
—
DTNF224R
DTNF225R
—
—
DTNF323R
DTNF324R
—
—
—
DTNF361R DTNF361J
DTNF362R DTNF362J
DTNF363R DTNF363J
DTNF364R DTNF364J
DTNF365R NF355HDTK
DTNF366R
DTNF367R
DTNF368R
NFR451DTK
NFR452DTK
NFR453DTK
NFR454DTK
NFR455DTK
NFR456DTK
NFR457DTK
Type 4X – Stainless Steel
Catalog Number
— —
— —
— —
— —
— —
— —
— —
— —
— —
— F353SSDTK
— F354SSDTK
F355SSDTK ➃
—
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
— —
DTNF361S
DTNF362S
DTNF363S
DTNF364S
NF355SSDTK
— —
— —
— —
— —
— —
— —
— NF454SSDTK
— —
— —
— —