Brochure

45
5/98
© 1998 Square D All Rights Reserved
Special Arrangements with Three Devices
Three Type S Contactors can be mechanically
interlocked so that only one contactor can be
energized at any one time. The mechanical
interlock, pictured in Figure 2, is an interference
(non-jamming) type locking at the beginning of the
stroke of any contactor.
Factory assembled units are listed in the table
below. Figures 1 and 2 show factory assembled
and wired devices. All contactors are both
electrically and mechanically interlocked. The
class and type numbers listed only cover the
contactor and/or starter mounting arrangement,
NEMA size of the devices, and the number of
poles. A power and control wiring diagram must
accompany each order. Additional electrical
interlocks are available factory (or field) installed
in the locations shown in Figure No. 2 and Table
No. 2, Page 52. 8810 starters are supplied with
melting alloy type thermal overload relays.
For customer assembled units, the basic
mechanical interlock and base assembly can be
purchased separately. Standard Class 8502
contactors and Class 8536 starters are used in
the locations and pole arrangement shown. If
Class 8536 starters are used, it is necessary to
mount a Class 9999 Type SO bracket below the
overload block to give the block support.
For electrically interlocking customer assembled
units a Class 9999 Type SX-12, normally closed
internal interlock and/or a Class 9999 Type SX-7,
normally closed external interlock can be used.
Ordering Information Required
1. Order complete factory assembled devices by
class and type number from table above.
2. Supply wiring diagram for power and control
connections as catalog number only covers
general contactor and starter mounting
arrangement.
3. Voltage and frequency of contactor coils.
4. Select additional factory assembled electrical
interlocks from table on Page 47 specifying
interlock position letter and whether interlock
is N.O. or N.C.
5. Example of ordering information required on
factory assembled devices:
(a) Class 8810 Type SCO-45
(b) Wired per diagram
(which must accompany order)
(c) All coils — 120 volts, 60 hertz
(d) Additional electrical interlocks:
C — N.O., E — N.C., and J — N.O.
6. For customer assembly of three mechanically
interlocked devices, order the mechanical
interlock and overload relay mounting
brackets by class and type numbers.
Thermal Units
Thermal units should be ordered separately. For
selection of thermal units, refer to the Catalog
Thermal Unit Selection Index R Digest. Use the
motor nameplate FLC’s (Full Load Currents) to
select thermal units.
A
B
C
D
No.
1
Cont.
E
F
G
H
No.
2
Cont.
J
K
L
M
No.
3
Cont.
OL-35
OL-1 OL-2 OL-3
Figure 2
Contactor, overload and external electrical
interlock positions
Three Mechanically Interlocked Contactors and Starters — Factory Assembled
Class Type
Contactor Position — See Figure 2
Overload
Relay
Position
See Fig. 3
Number of
Thermal
Units
Required
No. 1 Contactor
Size and Poles
No. 2 Contactor
Size and Poles
No. 3 Contactor
Size and Poles
NEMA Size 1
No. of Poles
NEMA Size 2
No. of Poles
NEMA Size 1
No. of Poles
NEMA Size 2
No. of Poles
NEMA Size 1
No. of Poles
NEMA Size 2
No. of Poles
8810
SCO-41 3 . . . 3 . . . 3 . . .
OL-2 & -3 6
SCO-42 4 . . . 3 . . . 3 . . .
SCO-43 . . . 3 3 . . . 3 . . .
SCO-44 . . . 4 3 . . . 3 . . .
SDO-41 . . . 3 . . . 3 . . . 3
SDO-42 . . . 4 . . . 3 . . . 3
8810
SCO-45 3 . . . 3 . . . 5 . . .
OL-2 & -3 6
SCO-46 4 . . . 3 . . . 5 . . .
SCO-47 . . . 3 3 . . . 5 . . .
SCO-48 . . . 4 3 . . . 5 . . .
SDO-43 . . . 3 . . . 3 . . . 5
SDO-44 . . . 4 . . . 3 . . . 5
AC Two Speed Magnetic Starters
Line Voltage — with Melting Alloy Overload Relays or Solid State Overload Relays – Class 8810