Effective July 2007
11
TRIP RESET
The Cutler-Hammer ATSBI Switch is supplied with
high interrupting molded case switches which
function as the power contacts for the Transfer
Switch, Isolation Switch, and Bypass Switches.
These Moulded Case Switches are equipped with
instantaneous releases which act to open the switch
only under high fault short circuit conditions. This
automatic opening (trip) function is a self protecting
feature that guarantees maximum contact life and
significantly reduces the need for contact
inspection, maintenance, or replacement as well as
offering maximum safety.
The instantaneous release have been specifically
designed and calibrated with a very high current
release point permit selective short circuit current
isolation by overcurrent protective devices closest to
the fault. This means that a short circuit fault
occurring downstream of the ATSBI equipment
would normally be cleared by a downstream breaker
or fuse and would not cause an automatic opening
of any of the Moulded Case Switches within the
unit.
In some instances a downstream short circuit could
cause an automatic opening within the ATSBI
equipment. The following instructions describe the
procedure for resetting an automatically opened
switch.
TRANSFER SWITCH RESET
The Automatic Transfer Switch is equipped with an
automatic switch reset feature. Should an ATS
Moulded Case Switch automatically open as a result
of a downstream short circuit condition, the ATS
logic will engage the Transfer Mechanism to
electrically reset the automatically opened switch.
If optional overcurrent protection (option 16,17, or
37) is provided, the automatic switch reset provision
is omitted. If one of these options is supplied, the
ATS will lockout electrical operation until the tripped
switch is reset by placing it in the off position
utilizing the manual operating handle located on the
transfer mechanism.
ISOLATION SWITCH RESET
An automatic opening of the Isolation Switch will be
visually indicated by a lit amber light on the Bypass
Isolation (upper) panel of the enclosure.
A TRIP CONDITION IS A RESULT OF A FAULTED
POWER CIRCUIT CONNECTED TO THE
EQUIPMENT. FAILURE TO CORRECT SUCH
FAULTED CONDITIONS CAN CAUSE SEVERE
EQUIPMENT OR CABLE DAMAGE, PRESENT A
POTENTIAL FIRE HAZARD, AND RESULT IN
DEATH OR PERSONAL INJURY.
IDENTIFY AND CORRECT THE FAULTED CIRCUIT
BEFORE ATTEMPTING TO RESET AUTOMATICALLY
OPENED SWITCHES WITHIN THE ATSBI
EQUIPMENT.
To Reset Isolation Switch:
100 - 1000 Amp Units
1.
Move Isolation handle down to “RESET”
position. This position is beyond the “OFF”
position and may require more downward force
then is used to open the switch only.
2. The lit “Isolated Mechanism Tripped” amber
light should turn off.
3. Move Isolation handle up to the “ON” position.
4. Verify that the white “Load Energized” light is lit.
BYPASS SWITCH RESET
An automatic opening of the Normal or Emergency
Bypass Switch will be visually indicated by a lit
amber light located on the Bypass Isolation (upper)
panel of the enclosure labeled “Bypass Tripped”.
I.L. 16913A
CAUTION
