Instructions / Assembly

AT20, AT40, AT72D, AT87, AT88 AT TRANSFORMERS
5 69-1641EF—01
Fig. 7. Tab on mounting plate fits in slot on
transformer mounting foot.
Fig. 8. Secure plate to transformer with mounting
screw.
Fig. 9. Location of mounting holes.
Mounting the AT87 Transformer
Foot Mounting (Fig. 10)
Use screws or bolts through slots in the mounting feet
to fasten the transformer to the mounting surface.
Fig. 10. Foot mounting of AT87 Transformer.
Plate Mounting
The mounting plate allows the transformer to be
mounted on a 4 in. by 4 in. square or 4 in. octagonal
junction box.
1. Remove the large center knockout in the mount-
ing plate (see Fig. 6).
2. Take transformer in one hand and mounting
plate in the other hand. Keyhole slots on mount-
ing plate should be up.
3. Place large knockout in mounting plate over
primary leadwires and end bell of transformer.
The small tab on the bottom center of the plate
fits into the slot in the transformer mounting
feet (see Fig. 7).
4. Insert the mounting screw through the holes as
illustrated (Fig. 8).
5. Secure plate to transformer. Do not overtighten
screw.
Mounting Transformer and Plate to
Electrical Box.
The mounting plate can be mounted in 4 in. x 4 in.
boxes with regular and irregular spaced mounting
holes, and on 4 in. octagonal boxes (Fig. 9).
1. Use the screws supplied with the junction box.
2. Place the screws through the appropriate
mounting holes in the plate and secure the
transformer and plate to the box.
3. Punch out appropriate knockouts for plate
mounting holes, as necessary.
NOTE: Transformer should always be outside of the
junction box.
Mounting the AT88 Transformer.
Use screws or bolts through slots in the mounting feet
to fasten the transformer to the mounting surface. See
Fig. 2.
M20855
SLOT
TA B
IM
POR
TAN
T
M
O
UNT
TRANSFO
RM
ER
OTHER SIDE
M9163
TRANSFORMER
PLATE
OCTAGON
BOX
M20658
IRREGULAR
4 X 4 INCH
BOX
(MOUNTING
HOLES IN
BOX ARE
SLIGHTLY
INDENTED)
REGULAR
4 X 4 INCH
BOX (2)
IRREGULAR
4 X 4 INCH
BOX
(MOUNTING
HOLES IN
BOX ARE
SLIGHTLY
INDENTED)
REGULAR
4 X 4 INCH
BOX (2)
OCTAGON
BOX
LOAD
N.E.C. CLASS 2
USE SCREWS OR
BOLTS THROUGH
SLOTS (4) IN
MOUNTING FEET
M20659
MOUNTING FOOT (2)
SCREW
TERMINALS
FOR
SECONDARY
CONNECTIONS
LEADWIRES
FOR PRIMARY
CONNECTIONS