Installation Manual
ASCO 3ATS, 3ADTS, 3NTS, 3NDTS
381333-406
ASCO Power Technologies
Page 3
maintenance
h dl
Clockwise DOWN closes
the Normal source
contacts (lower) and
opens the Emergency
source contacts (upper)
Counterclockwise DOWN
closes the Emergency
source contacts (upper)
and opens the Normal
source contacts (lower)
Clockwise DOWN CLOSES
the contacts
Pull out shaft to close
Emergency source contacts
(upper)
Push in shaft to close
Normal source contacts
(lower)
Counterclockwise DOWN
OPENS the contacts
Pull out shaft to open
Emergency source contacts
(upper)
Push in shaft to open Normal
source contacts (lower)
maintenance handle
insert handle into
hole in hub
slide hub onto shaft
and insert the pin
Functional Test
The functional test consists of three checks: manual
operation, voltage checks, and electrical operation.
Do these checks in the order presented to avoid
damaging the transfer switch.
1 – Manual Operation
A maintenance handle is provided on the transfer switch for
maintenance purposes only. Manual operation of the transfer
switch should be checked before it is energized (operated
electrically).
Do not manually operate the transfer switch until
both power sources are disconnected: open both
circuit breakers.
1.
After deenergizing both power sources, open the enclosure
door. Locate and remove the maintenance handle from the
clip on the left side of the transfer switch. See Figures 3, 4,
and 5. See Figure 2 for the contact position indicators.
2.
Install the handle into the hole in the molded hub. Move
the handle up or down as shown to manually operate the
transfer switch. It should operate smoothly without any
binding. If it does not, check for shipping damage or
construction debris.
3.
3ADTS and 3NTS have two contact shaft hubs. See
Figure 5.
4.
Return the transfer switch to the Normal position.
Note: If Normal and Emergency connections are reversed this
operation is also reversed.
Figure 3. Maintenance handle on 3ATS & 3NTS.
Figure 4. Maintenance handle operation on 3ATS &
3NTS.
Figure 5. Maintenance handle on 3ADTS & 3NDTS.
NOTICE
WARNING
!
